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7687 lines
292 KiB
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<title>FFmpeg Codecs Documentation</title>
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<meta name="description" content="FFmpeg Codecs Documentation">
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<meta name="keywords" content="FFmpeg Codecs Documentation">
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<div class="top-level-extent" id="SEC_Top">
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<div class="element-contents" id="SEC_Contents">
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<h2 class="contents-heading">Table of Contents</h2>
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<div class="contents">
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<ul class="toc-numbered-mark">
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<li><a id="toc-Description" href="#Description">1 Description</a></li>
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<li><a id="toc-Codec-Options" href="#Codec-Options">2 Codec Options</a></li>
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<li><a id="toc-Decoders" href="#Decoders">3 Decoders</a></li>
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<li><a id="toc-Video-Decoders" href="#Video-Decoders">4 Video Decoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-av1" href="#av1">4.1 av1</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options" href="#Options">4.1.1 Options</a></li>
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</ul></li>
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<li><a id="toc-rawvideo" href="#rawvideo">4.2 rawvideo</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-1" href="#Options-1">4.2.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libdav1d" href="#libdav1d">4.3 libdav1d</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-2" href="#Options-2">4.3.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libdavs2" href="#libdavs2">4.4 libdavs2</a></li>
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<li><a id="toc-libuavs3d" href="#libuavs3d">4.5 libuavs3d</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-3" href="#Options-3">4.5.1 Options</a></li>
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</ul></li>
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<li><a id="toc-QSV-Decoders" href="#QSV-Decoders">4.6 QSV Decoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Common-Options" href="#Common-Options">4.6.1 Common Options</a></li>
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<li><a id="toc-HEVC-Options" href="#HEVC-Options">4.6.2 HEVC Options</a></li>
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</ul></li>
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<li><a id="toc-v210" href="#v210">4.7 v210</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-4" href="#Options-4">4.7.1 Options</a></li>
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</ul></li>
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</ul></li>
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<li><a id="toc-Audio-Decoders" href="#Audio-Decoders">5 Audio Decoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-ac3" href="#ac3">5.1 ac3</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-AC_002d3-Decoder-Options" href="#AC_002d3-Decoder-Options">5.1.1 AC-3 Decoder Options</a></li>
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</ul></li>
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<li><a id="toc-flac-1" href="#flac-1">5.2 flac</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-FLAC-Decoder-options" href="#FLAC-Decoder-options">5.2.1 FLAC Decoder options</a></li>
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</ul></li>
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<li><a id="toc-ffwavesynth" href="#ffwavesynth">5.3 ffwavesynth</a></li>
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<li><a id="toc-libcelt" href="#libcelt">5.4 libcelt</a></li>
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<li><a id="toc-libgsm" href="#libgsm">5.5 libgsm</a></li>
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<li><a id="toc-libilbc" href="#libilbc">5.6 libilbc</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-5" href="#Options-5">5.6.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libopencore_002damrnb" href="#libopencore_002damrnb">5.7 libopencore-amrnb</a></li>
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<li><a id="toc-libopencore_002damrwb" href="#libopencore_002damrwb">5.8 libopencore-amrwb</a></li>
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<li><a id="toc-libopus" href="#libopus">5.9 libopus</a></li>
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</ul></li>
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<li><a id="toc-Subtitles-Decoders" href="#Subtitles-Decoders">6 Subtitles Decoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-libaribb24" href="#libaribb24">6.1 libaribb24</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-libaribb24-Decoder-Options" href="#libaribb24-Decoder-Options">6.1.1 libaribb24 Decoder Options</a></li>
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</ul></li>
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<li><a id="toc-libaribcaption" href="#libaribcaption">6.2 libaribcaption</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-libaribcaption-Decoder-Options" href="#libaribcaption-Decoder-Options">6.2.1 libaribcaption Decoder Options</a></li>
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<li><a id="toc-libaribcaption-decoder-usage-examples" href="#libaribcaption-decoder-usage-examples">6.2.2 libaribcaption decoder usage examples</a></li>
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</ul></li>
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<li><a id="toc-dvbsub" href="#dvbsub">6.3 dvbsub</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-6" href="#Options-6">6.3.1 Options</a></li>
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</ul></li>
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<li><a id="toc-dvdsub" href="#dvdsub">6.4 dvdsub</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-7" href="#Options-7">6.4.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libzvbi_002dteletext" href="#libzvbi_002dteletext">6.5 libzvbi-teletext</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-8" href="#Options-8">6.5.1 Options</a></li>
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</ul></li>
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</ul></li>
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<li><a id="toc-Encoders" href="#Encoders">7 Encoders</a></li>
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<li><a id="toc-Audio-Encoders" href="#Audio-Encoders">8 Audio Encoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-aac" href="#aac">8.1 aac</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-9" href="#Options-9">8.1.1 Options</a></li>
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</ul></li>
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<li><a id="toc-ac3-and-ac3_005ffixed" href="#ac3-and-ac3_005ffixed">8.2 ac3 and ac3_fixed</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-AC_002d3-Metadata" href="#AC_002d3-Metadata">8.2.1 AC-3 Metadata</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Metadata-Control-Options" href="#Metadata-Control-Options">8.2.1.1 Metadata Control Options</a></li>
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<li><a id="toc-Downmix-Levels" href="#Downmix-Levels">8.2.1.2 Downmix Levels</a></li>
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<li><a id="toc-Audio-Production-Information" href="#Audio-Production-Information">8.2.1.3 Audio Production Information</a></li>
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<li><a id="toc-Other-Metadata-Options" href="#Other-Metadata-Options">8.2.1.4 Other Metadata Options</a></li>
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</ul></li>
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<li><a id="toc-Extended-Bitstream-Information" href="#Extended-Bitstream-Information">8.2.2 Extended Bitstream Information</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Extended-Bitstream-Information-_002d-Part-1" href="#Extended-Bitstream-Information-_002d-Part-1">8.2.2.1 Extended Bitstream Information - Part 1</a></li>
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<li><a id="toc-Extended-Bitstream-Information-_002d-Part-2" href="#Extended-Bitstream-Information-_002d-Part-2">8.2.2.2 Extended Bitstream Information - Part 2</a></li>
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</ul></li>
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<li><a id="toc-Other-AC_002d3-Encoding-Options" href="#Other-AC_002d3-Encoding-Options">8.2.3 Other AC-3 Encoding Options</a></li>
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<li><a id="toc-Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options" href="#Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options">8.2.4 Floating-Point-Only AC-3 Encoding Options</a></li>
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</ul></li>
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<li><a id="toc-flac-2" href="#flac-2">8.3 flac</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-10" href="#Options-10">8.3.1 Options</a></li>
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</ul></li>
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<li><a id="toc-opus" href="#opus">8.4 opus</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-11" href="#Options-11">8.4.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libfdk_005faac" href="#libfdk_005faac">8.5 libfdk_aac</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-12" href="#Options-12">8.5.1 Options</a></li>
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<li><a id="toc-Examples" href="#Examples">8.5.2 Examples</a></li>
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</ul></li>
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<li><a id="toc-libmp3lame-1" href="#libmp3lame-1">8.6 libmp3lame</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-13" href="#Options-13">8.6.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libopencore_002damrnb-1" href="#libopencore_002damrnb-1">8.7 libopencore-amrnb</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-14" href="#Options-14">8.7.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libopus-1" href="#libopus-1">8.8 libopus</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Option-Mapping" href="#Option-Mapping">8.8.1 Option Mapping</a></li>
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</ul></li>
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<li><a id="toc-libshine-1" href="#libshine-1">8.9 libshine</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-15" href="#Options-15">8.9.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libtwolame" href="#libtwolame">8.10 libtwolame</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-16" href="#Options-16">8.10.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libvo_002damrwbenc" href="#libvo_002damrwbenc">8.11 libvo-amrwbenc</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-17" href="#Options-17">8.11.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libvorbis" href="#libvorbis">8.12 libvorbis</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-18" href="#Options-18">8.12.1 Options</a></li>
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</ul></li>
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<li><a id="toc-mjpeg" href="#mjpeg">8.13 mjpeg</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-19" href="#Options-19">8.13.1 Options</a></li>
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</ul></li>
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<li><a id="toc-wavpack" href="#wavpack">8.14 wavpack</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-20" href="#Options-20">8.14.1 Options</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Shared-options" href="#Shared-options">8.14.1.1 Shared options</a></li>
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<li><a id="toc-Private-options" href="#Private-options">8.14.1.2 Private options</a></li>
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</ul></li>
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</ul></li>
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</ul></li>
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<li><a id="toc-Video-Encoders" href="#Video-Encoders">9 Video Encoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-a64_005fmulti_002c-a64_005fmulti5" href="#a64_005fmulti_002c-a64_005fmulti5">9.1 a64_multi, a64_multi5</a></li>
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<li><a id="toc-Cinepak" href="#Cinepak">9.2 Cinepak</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-21" href="#Options-21">9.2.1 Options</a></li>
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</ul></li>
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<li><a id="toc-GIF" href="#GIF">9.3 GIF</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-22" href="#Options-22">9.3.1 Options</a></li>
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</ul></li>
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<li><a id="toc-Hap" href="#Hap">9.4 Hap</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-23" href="#Options-23">9.4.1 Options</a></li>
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</ul></li>
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<li><a id="toc-jpeg2000" href="#jpeg2000">9.5 jpeg2000</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-24" href="#Options-24">9.5.1 Options</a></li>
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</ul></li>
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<li><a id="toc-librav1e" href="#librav1e">9.6 librav1e</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-25" href="#Options-25">9.6.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libaom_002dav1" href="#libaom_002dav1">9.7 libaom-av1</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-26" href="#Options-26">9.7.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libsvtav1" href="#libsvtav1">9.8 libsvtav1</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-27" href="#Options-27">9.8.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libjxl" href="#libjxl">9.9 libjxl</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-28" href="#Options-28">9.9.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libkvazaar" href="#libkvazaar">9.10 libkvazaar</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-29" href="#Options-29">9.10.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libopenh264" href="#libopenh264">9.11 libopenh264</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-30" href="#Options-30">9.11.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libtheora" href="#libtheora">9.12 libtheora</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-31" href="#Options-31">9.12.1 Options</a></li>
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<li><a id="toc-Examples-1" href="#Examples-1">9.12.2 Examples</a></li>
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</ul></li>
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<li><a id="toc-libvpx" href="#libvpx">9.13 libvpx</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-32" href="#Options-32">9.13.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libwebp" href="#libwebp">9.14 libwebp</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Pixel-Format" href="#Pixel-Format">9.14.1 Pixel Format</a></li>
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<li><a id="toc-Options-33" href="#Options-33">9.14.2 Options</a></li>
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</ul></li>
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<li><a id="toc-libx264_002c-libx264rgb" href="#libx264_002c-libx264rgb">9.15 libx264, libx264rgb</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Supported-Pixel-Formats" href="#Supported-Pixel-Formats">9.15.1 Supported Pixel Formats</a></li>
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<li><a id="toc-Options-34" href="#Options-34">9.15.2 Options</a></li>
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</ul></li>
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<li><a id="toc-libx265" href="#libx265">9.16 libx265</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-35" href="#Options-35">9.16.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libxavs2" href="#libxavs2">9.17 libxavs2</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-36" href="#Options-36">9.17.1 Options</a></li>
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</ul></li>
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<li><a id="toc-libxvid" href="#libxvid">9.18 libxvid</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-37" href="#Options-37">9.18.1 Options</a></li>
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</ul></li>
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<li><a id="toc-MediaFoundation" href="#MediaFoundation">9.19 MediaFoundation</a></li>
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<li><a id="toc-mpeg2" href="#mpeg2">9.20 mpeg2</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Options-38" href="#Options-38">9.20.1 Options</a></li>
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</ul></li>
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<li><a id="toc-png" href="#png">9.21 png</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Private-options-1" href="#Private-options-1">9.21.1 Private options</a></li>
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</ul></li>
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<li><a id="toc-ProRes" href="#ProRes">9.22 ProRes</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Private-Options-for-prores_002dks" href="#Private-Options-for-prores_002dks">9.22.1 Private Options for prores-ks</a></li>
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<li><a id="toc-Speed-considerations" href="#Speed-considerations">9.22.2 Speed considerations</a></li>
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</ul></li>
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<li><a id="toc-QSV-Encoders" href="#QSV-Encoders">9.23 QSV Encoders</a>
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<ul class="toc-numbered-mark">
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<li><a id="toc-Ratecontrol-Method" href="#Ratecontrol-Method">9.23.1 Ratecontrol Method</a></li>
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<li><a id="toc-Global-Options-_002d_003e-MSDK-Options" href="#Global-Options-_002d_003e-MSDK-Options">9.23.2 Global Options -> MSDK Options</a></li>
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<li><a id="toc-Common-Options-1" href="#Common-Options-1">9.23.3 Common Options</a></li>
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<li><a id="toc-Runtime-Options" href="#Runtime-Options">9.23.4 Runtime Options</a></li>
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<li><a id="toc-H264-options" href="#H264-options">9.23.5 H264 options</a></li>
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<li><a id="toc-HEVC-Options-1" href="#HEVC-Options-1">9.23.6 HEVC Options</a></li>
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<li><a id="toc-MPEG2-Options" href="#MPEG2-Options">9.23.7 MPEG2 Options</a></li>
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<li><a id="toc-VP9-Options" href="#VP9-Options">9.23.8 VP9 Options</a></li>
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<li><a id="toc-AV1-Options" href="#AV1-Options">9.23.9 AV1 Options</a></li>
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</ul></li>
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<li><a id="toc-snow" href="#snow">9.24 snow</a>
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<ul class="toc-numbered-mark">
|
|
<li><a id="toc-Options-39" href="#Options-39">9.24.1 Options</a></li>
|
|
</ul></li>
|
|
<li><a id="toc-VAAPI-encoders" href="#VAAPI-encoders">9.25 VAAPI encoders</a></li>
|
|
<li><a id="toc-vbn" href="#vbn">9.26 vbn</a>
|
|
<ul class="toc-numbered-mark">
|
|
<li><a id="toc-Options-40" href="#Options-40">9.26.1 Options</a></li>
|
|
</ul></li>
|
|
<li><a id="toc-vc2" href="#vc2">9.27 vc2</a>
|
|
<ul class="toc-numbered-mark">
|
|
<li><a id="toc-Options-41" href="#Options-41">9.27.1 Options</a></li>
|
|
</ul></li>
|
|
</ul></li>
|
|
<li><a id="toc-Subtitles-Encoders" href="#Subtitles-Encoders">10 Subtitles Encoders</a>
|
|
<ul class="toc-numbered-mark">
|
|
<li><a id="toc-dvdsub-1" href="#dvdsub-1">10.1 dvdsub</a>
|
|
<ul class="toc-numbered-mark">
|
|
<li><a id="toc-Options-42" href="#Options-42">10.1.1 Options</a></li>
|
|
</ul></li>
|
|
</ul></li>
|
|
<li><a id="toc-See-Also" href="#See-Also">11 See Also</a></li>
|
|
<li><a id="toc-Authors" href="#Authors">12 Authors</a></li>
|
|
</ul>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Description">
|
|
<h2 class="chapter">1 Description</h2>
|
|
|
|
<p>This document describes the codecs (decoders and encoders) provided by
|
|
the libavcodec library.
|
|
</p>
|
|
|
|
<a class="anchor" id="codec_002doptions"></a></div>
|
|
<div class="chapter-level-extent" id="Codec-Options">
|
|
<h2 class="chapter">2 Codec Options</h2>
|
|
|
|
<p>libavcodec provides some generic global options, which can be set on
|
|
all the encoders and decoders. In addition each codec may support
|
|
so-called private options, which are specific for a given codec.
|
|
</p>
|
|
<p>Sometimes, a global option may only affect a specific kind of codec,
|
|
and may be nonsensical or ignored by another, so you need to be aware
|
|
of the meaning of the specified options. Also some options are
|
|
meant only for decoding or encoding.
|
|
</p>
|
|
<p>Options may be set by specifying -<var class="var">option</var> <var class="var">value</var> in the
|
|
FFmpeg tools, or by setting the value explicitly in the
|
|
<code class="code">AVCodecContext</code> options or using the <samp class="file">libavutil/opt.h</samp> API
|
|
for programmatic use.
|
|
</p>
|
|
<p>The list of supported options follow:
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set bitrate in bits/s. Default value is 200K.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ab <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set audio bitrate (in bits/s). Default value is 128K.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bt <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate
|
|
tolerance specifies how far ratecontrol is willing to deviate from the
|
|
target average bitrate value. This is not related to min/max
|
|
bitrate. Lowering tolerance too much has an adverse effect on quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">flags <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt>
|
|
<dd><p>Set generic flags.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">mv4</samp>’</dt>
|
|
<dd><p>Use four motion vector by macroblock (mpeg4).
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">qpel</samp>’</dt>
|
|
<dd><p>Use 1/4 pel motion compensation.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">loop</samp>’</dt>
|
|
<dd><p>Use loop filter.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">qscale</samp>’</dt>
|
|
<dd><p>Use fixed qscale.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">pass1</samp>’</dt>
|
|
<dd><p>Use internal 2pass ratecontrol in first pass mode.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">pass2</samp>’</dt>
|
|
<dd><p>Use internal 2pass ratecontrol in second pass mode.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">gray</samp>’</dt>
|
|
<dd><p>Only decode/encode grayscale.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>Set error[?] variables during encoding.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">truncated</samp>’</dt>
|
|
<dd><p>Input bitstream might be randomly truncated.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">drop_changed</samp>’</dt>
|
|
<dd><p>Don’t output frames whose parameters differ from first decoded frame in stream.
|
|
Error AVERROR_INPUT_CHANGED is returned when a frame is dropped.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">ildct</samp>’</dt>
|
|
<dd><p>Use interlaced DCT.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">low_delay</samp>’</dt>
|
|
<dd><p>Force low delay.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">global_header</samp>’</dt>
|
|
<dd><p>Place global headers in extradata instead of every keyframe.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bitexact</samp>’</dt>
|
|
<dd><p>Only write platform-, build- and time-independent data. (except (I)DCT).
|
|
This ensures that file and data checksums are reproducible and match between
|
|
platforms. Its primary use is for regression testing.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">aic</samp>’</dt>
|
|
<dd><p>Apply H263 advanced intra coding / mpeg4 ac prediction.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ilme</samp>’</dt>
|
|
<dd><p>Apply interlaced motion estimation.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">cgop</samp>’</dt>
|
|
<dd><p>Use closed gop.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">output_corrupt</samp>’</dt>
|
|
<dd><p>Output even potentially corrupted frames.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">time_base <var class="var">rational number</var></samp></dt>
|
|
<dd><p>Set codec time base.
|
|
</p>
|
|
<p>It is the fundamental unit of time (in seconds) in terms of which
|
|
frame timestamps are represented. For fixed-fps content, timebase
|
|
should be <code class="code">1 / frame_rate</code> and timestamp increments should be
|
|
identically 1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">g <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set the group of picture (GOP) size. Default value is 12.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ar <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set audio sampling rate (in Hz).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ac <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set number of audio channels.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set cutoff bandwidth. (Supported only by selected encoders, see
|
|
their respective documentation sections.)
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame_size <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set audio frame size.
|
|
</p>
|
|
<p>Each submitted frame except the last must contain exactly frame_size
|
|
samples per channel. May be 0 when the codec has
|
|
CODEC_CAP_VARIABLE_FRAME_SIZE set, in that case the frame size is not
|
|
restricted. It is set by some decoders to indicate constant frame
|
|
size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame_number <var class="var">integer</var></samp></dt>
|
|
<dd><p>Set the frame number.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">delay <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">qcomp <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set video quantizer scale compression (VBR). It is used as a constant
|
|
in the ratecontrol equation. Recommended range for default rc_eq:
|
|
0.0-1.0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qblur <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set video quantizer scale blur (VBR).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmin <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set min video quantizer scale (VBR). Must be included between -1 and
|
|
69, default value is 2.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmax <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set max video quantizer scale (VBR). Must be included between -1 and
|
|
1024, default value is 31.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qdiff <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set max difference between the quantizer scale (VBR).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bf <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set max number of B frames between non-B-frames.
|
|
</p>
|
|
<p>Must be an integer between -1 and 16. 0 means that B-frames are
|
|
disabled. If a value of -1 is used, it will choose an automatic value
|
|
depending on the encoder.
|
|
</p>
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">b_qfactor <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set qp factor between P and B frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">codec_tag <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">bug <var class="var">flags</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Workaround not auto detected encoder bugs.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">autodetect</samp>’</dt>
|
|
<dt>‘<samp class="samp">xvid_ilace</samp>’</dt>
|
|
<dd><p>Xvid interlacing bug (autodetected if fourcc==XVIX)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ump4</samp>’</dt>
|
|
<dd><p>(autodetected if fourcc==UMP4)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">no_padding</samp>’</dt>
|
|
<dd><p>padding bug (autodetected)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">amv</samp>’</dt>
|
|
<dt>‘<samp class="samp">qpel_chroma</samp>’</dt>
|
|
<dt>‘<samp class="samp">std_qpel</samp>’</dt>
|
|
<dd><p>old standard qpel (autodetected per fourcc/version)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">qpel_chroma2</samp>’</dt>
|
|
<dt>‘<samp class="samp">direct_blocksize</samp>’</dt>
|
|
<dd><p>direct-qpel-blocksize bug (autodetected per fourcc/version)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">edge</samp>’</dt>
|
|
<dd><p>edge padding bug (autodetected per fourcc/version)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">hpel_chroma</samp>’</dt>
|
|
<dt>‘<samp class="samp">dc_clip</samp>’</dt>
|
|
<dt>‘<samp class="samp">ms</samp>’</dt>
|
|
<dd><p>Workaround various bugs in microsoft broken decoders.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">trunc</samp>’</dt>
|
|
<dd><p>trancated frames
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">strict <var class="var">integer</var> (<em class="emph">decoding/encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Specify how strictly to follow the standards.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">very</samp>’</dt>
|
|
<dd><p>strictly conform to an older more strict version of the spec or reference software
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">strict</samp>’</dt>
|
|
<dd><p>strictly conform to all the things in the spec no matter what consequences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">normal</samp>’</dt>
|
|
<dt>‘<samp class="samp">unofficial</samp>’</dt>
|
|
<dd><p>allow unofficial extensions
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">experimental</samp>’</dt>
|
|
<dd><p>allow non standardized experimental things, experimental
|
|
(unfinished/work in progress/not well tested) decoders and encoders.
|
|
Note: experimental decoders can pose a security risk, do not use this for
|
|
decoding untrusted input.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">b_qoffset <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set QP offset between P and B frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">err_detect <var class="var">flags</var> (<em class="emph">decoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set error detection flags.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">crccheck</samp>’</dt>
|
|
<dd><p>verify embedded CRCs
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bitstream</samp>’</dt>
|
|
<dd><p>detect bitstream specification deviations
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">buffer</samp>’</dt>
|
|
<dd><p>detect improper bitstream length
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">explode</samp>’</dt>
|
|
<dd><p>abort decoding on minor error detection
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ignore_err</samp>’</dt>
|
|
<dd><p>ignore decoding errors, and continue decoding.
|
|
This is useful if you want to analyze the content of a video and thus want
|
|
everything to be decoded no matter what. This option will not result in a video
|
|
that is pleasing to watch in case of errors.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">careful</samp>’</dt>
|
|
<dd><p>consider things that violate the spec and have not been seen in the wild as errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">compliant</samp>’</dt>
|
|
<dd><p>consider all spec non compliancies as errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">aggressive</samp>’</dt>
|
|
<dd><p>consider things that a sane encoder should not do as an error
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">has_b_frames <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">block_align <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">rc_override_count <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">maxrate <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set max bitrate tolerance (in bits/s). Requires bufsize to be set.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minrate <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set min bitrate tolerance (in bits/s). Most useful in setting up a CBR
|
|
encode. It is of little use elsewise.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bufsize <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set ratecontrol buffer size (in bits).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">i_qfactor <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set QP factor between P and I frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">i_qoffset <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set QP offset between P and I frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">dct <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set DCT algorithm.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dd><p>autoselect a good one (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">fastint</samp>’</dt>
|
|
<dd><p>fast integer
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">int</samp>’</dt>
|
|
<dd><p>accurate integer
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">mmx</samp>’</dt>
|
|
<dt>‘<samp class="samp">altivec</samp>’</dt>
|
|
<dt>‘<samp class="samp">faan</samp>’</dt>
|
|
<dd><p>floating point AAN DCT
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">lumi_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Compress bright areas stronger than medium ones.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tcplx_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set temporal complexity masking.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">scplx_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set spatial complexity masking.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">p_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set inter masking.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">dark_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Compress dark areas stronger than medium ones.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">idct <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Select IDCT implementation.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dt>‘<samp class="samp">int</samp>’</dt>
|
|
<dt>‘<samp class="samp">simple</samp>’</dt>
|
|
<dt>‘<samp class="samp">simplemmx</samp>’</dt>
|
|
<dt>‘<samp class="samp">simpleauto</samp>’</dt>
|
|
<dd><p>Automatically pick a IDCT compatible with the simple one
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">arm</samp>’</dt>
|
|
<dt>‘<samp class="samp">altivec</samp>’</dt>
|
|
<dt>‘<samp class="samp">sh4</samp>’</dt>
|
|
<dt>‘<samp class="samp">simplearm</samp>’</dt>
|
|
<dt>‘<samp class="samp">simplearmv5te</samp>’</dt>
|
|
<dt>‘<samp class="samp">simplearmv6</samp>’</dt>
|
|
<dt>‘<samp class="samp">simpleneon</samp>’</dt>
|
|
<dt>‘<samp class="samp">xvid</samp>’</dt>
|
|
<dt>‘<samp class="samp">faani</samp>’</dt>
|
|
<dd><p>floating point AAN IDCT
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">slice_count <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">ec <var class="var">flags</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Set error concealment strategy.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">guess_mvs</samp>’</dt>
|
|
<dd><p>iterative motion vector (MV) search (slow)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">deblock</samp>’</dt>
|
|
<dd><p>use strong deblock filter for damaged MBs
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">favor_inter</samp>’</dt>
|
|
<dd><p>favor predicting from the previous frame instead of the current
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">bits_per_coded_sample <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">aspect <var class="var">rational number</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set sample aspect ratio.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sar <var class="var">rational number</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set sample aspect ratio. Alias to <var class="var">aspect</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">debug <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt>
|
|
<dd><p>Print specific debug info.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">pict</samp>’</dt>
|
|
<dd><p>picture info
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rc</samp>’</dt>
|
|
<dd><p>rate control
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bitstream</samp>’</dt>
|
|
<dt>‘<samp class="samp">mb_type</samp>’</dt>
|
|
<dd><p>macroblock (MB) type
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">qp</samp>’</dt>
|
|
<dd><p>per-block quantization parameter (QP)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct_coeff</samp>’</dt>
|
|
<dt>‘<samp class="samp">green_metadata</samp>’</dt>
|
|
<dd><p>display complexity metadata for the upcoming frame, GoP or for a given duration.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">skip</samp>’</dt>
|
|
<dt>‘<samp class="samp">startcode</samp>’</dt>
|
|
<dt>‘<samp class="samp">er</samp>’</dt>
|
|
<dd><p>error recognition
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">mmco</samp>’</dt>
|
|
<dd><p>memory management control operations (H.264)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bugs</samp>’</dt>
|
|
<dt>‘<samp class="samp">buffers</samp>’</dt>
|
|
<dd><p>picture buffer allocations
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">thread_ops</samp>’</dt>
|
|
<dd><p>threading operations
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nomc</samp>’</dt>
|
|
<dd><p>skip motion compensation
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">cmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set full pel me compare function.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>sum of absolute differences, fast (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">sse</samp>’</dt>
|
|
<dd><p>sum of squared errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">satd</samp>’</dt>
|
|
<dd><p>sum of absolute Hadamard transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct</samp>’</dt>
|
|
<dd><p>sum of absolute DCT transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>sum of squared quantization errors (avoid, low quality)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bit</samp>’</dt>
|
|
<dd><p>number of bits needed for the block
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>rate distortion optimal, slow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>0
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsad</samp>’</dt>
|
|
<dd><p>sum of absolute vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsse</samp>’</dt>
|
|
<dd><p>sum of squared vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nsse</samp>’</dt>
|
|
<dd><p>noise preserving sum of squared differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w53</samp>’</dt>
|
|
<dd><p>5/3 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w97</samp>’</dt>
|
|
<dd><p>9/7 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dctmax</samp>’</dt>
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">subcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set sub pel me compare function.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>sum of absolute differences, fast (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">sse</samp>’</dt>
|
|
<dd><p>sum of squared errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">satd</samp>’</dt>
|
|
<dd><p>sum of absolute Hadamard transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct</samp>’</dt>
|
|
<dd><p>sum of absolute DCT transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>sum of squared quantization errors (avoid, low quality)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bit</samp>’</dt>
|
|
<dd><p>number of bits needed for the block
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>rate distortion optimal, slow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>0
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsad</samp>’</dt>
|
|
<dd><p>sum of absolute vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsse</samp>’</dt>
|
|
<dd><p>sum of squared vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nsse</samp>’</dt>
|
|
<dd><p>noise preserving sum of squared differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w53</samp>’</dt>
|
|
<dd><p>5/3 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w97</samp>’</dt>
|
|
<dd><p>9/7 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dctmax</samp>’</dt>
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">mbcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set macroblock compare function.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>sum of absolute differences, fast (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">sse</samp>’</dt>
|
|
<dd><p>sum of squared errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">satd</samp>’</dt>
|
|
<dd><p>sum of absolute Hadamard transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct</samp>’</dt>
|
|
<dd><p>sum of absolute DCT transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>sum of squared quantization errors (avoid, low quality)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bit</samp>’</dt>
|
|
<dd><p>number of bits needed for the block
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>rate distortion optimal, slow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>0
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsad</samp>’</dt>
|
|
<dd><p>sum of absolute vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsse</samp>’</dt>
|
|
<dd><p>sum of squared vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nsse</samp>’</dt>
|
|
<dd><p>noise preserving sum of squared differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w53</samp>’</dt>
|
|
<dd><p>5/3 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w97</samp>’</dt>
|
|
<dd><p>9/7 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dctmax</samp>’</dt>
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">ildctcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set interlaced dct compare function.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>sum of absolute differences, fast (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">sse</samp>’</dt>
|
|
<dd><p>sum of squared errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">satd</samp>’</dt>
|
|
<dd><p>sum of absolute Hadamard transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct</samp>’</dt>
|
|
<dd><p>sum of absolute DCT transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>sum of squared quantization errors (avoid, low quality)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bit</samp>’</dt>
|
|
<dd><p>number of bits needed for the block
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>rate distortion optimal, slow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>0
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsad</samp>’</dt>
|
|
<dd><p>sum of absolute vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsse</samp>’</dt>
|
|
<dd><p>sum of squared vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nsse</samp>’</dt>
|
|
<dd><p>noise preserving sum of squared differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w53</samp>’</dt>
|
|
<dd><p>5/3 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w97</samp>’</dt>
|
|
<dd><p>9/7 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dctmax</samp>’</dt>
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">dia_size <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set diamond type & size for motion estimation.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">(1024, INT_MAX)</samp>’</dt>
|
|
<dd><p>full motion estimation(slowest)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">(768, 1024]</samp>’</dt>
|
|
<dd><p>umh motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">(512, 768]</samp>’</dt>
|
|
<dd><p>hex motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">(256, 512]</samp>’</dt>
|
|
<dd><p>l2s diamond motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">[2,256]</samp>’</dt>
|
|
<dd><p>var diamond motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">(-1, 2)</samp>’</dt>
|
|
<dd><p>small diamond motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">-1</samp>’</dt>
|
|
<dd><p>funny diamond motion estimation
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">(INT_MIN, -1)</samp>’</dt>
|
|
<dd><p>sab diamond motion estimation
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">last_pred <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set amount of motion predictors from the previous frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">precmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set pre motion estimation compare function.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>sum of absolute differences, fast (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">sse</samp>’</dt>
|
|
<dd><p>sum of squared errors
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">satd</samp>’</dt>
|
|
<dd><p>sum of absolute Hadamard transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dct</samp>’</dt>
|
|
<dd><p>sum of absolute DCT transformed differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">psnr</samp>’</dt>
|
|
<dd><p>sum of squared quantization errors (avoid, low quality)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bit</samp>’</dt>
|
|
<dd><p>number of bits needed for the block
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>rate distortion optimal, slow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>0
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsad</samp>’</dt>
|
|
<dd><p>sum of absolute vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vsse</samp>’</dt>
|
|
<dd><p>sum of squared vertical differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">nsse</samp>’</dt>
|
|
<dd><p>noise preserving sum of squared differences
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w53</samp>’</dt>
|
|
<dd><p>5/3 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">w97</samp>’</dt>
|
|
<dd><p>9/7 wavelet, only used in snow
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dctmax</samp>’</dt>
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">pre_dia_size <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set diamond type & size for motion estimation pre-pass.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">subq <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set sub pel motion estimation quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">me_range <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set limit motion vectors range (1023 for DivX player).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">global_quality <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dt><samp class="option">slice_flags <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">mbd <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set macroblock decision algorithm (high quality mode).
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">simple</samp>’</dt>
|
|
<dd><p>use mbcmp (default)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bits</samp>’</dt>
|
|
<dd><p>use fewest bits
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>use best rate distortion
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">rc_init_occupancy <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set number of bits which should be loaded into the rc buffer before
|
|
decoding starts.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">flags2 <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt>
|
|
<dd>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">fast</samp>’</dt>
|
|
<dd><p>Allow non spec compliant speedup tricks.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">noout</samp>’</dt>
|
|
<dd><p>Skip bitstream encoding.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ignorecrop</samp>’</dt>
|
|
<dd><p>Ignore cropping information from sps.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">local_header</samp>’</dt>
|
|
<dd><p>Place global headers at every keyframe instead of in extradata.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">chunks</samp>’</dt>
|
|
<dd><p>Frame data might be split into multiple chunks.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">showall</samp>’</dt>
|
|
<dd><p>Show all frames before the first keyframe.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">export_mvs</samp>’</dt>
|
|
<dd><p>Export motion vectors into frame side-data (see <code class="code">AV_FRAME_DATA_MOTION_VECTORS</code>)
|
|
for codecs that support it. See also <samp class="file">doc/examples/export_mvs.c</samp>.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">skip_manual</samp>’</dt>
|
|
<dd><p>Do not skip samples and export skip information as frame side data.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ass_ro_flush_noop</samp>’</dt>
|
|
<dd><p>Do not reset ASS ReadOrder field on flush.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">icc_profiles</samp>’</dt>
|
|
<dd><p>Generate/parse embedded ICC profiles from/to colorimetry tags.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">export_side_data <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt>
|
|
<dd>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">mvs</samp>’</dt>
|
|
<dd><p>Export motion vectors into frame side-data (see <code class="code">AV_FRAME_DATA_MOTION_VECTORS</code>)
|
|
for codecs that support it. See also <samp class="file">doc/examples/export_mvs.c</samp>.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">prft</samp>’</dt>
|
|
<dd><p>Export encoder Producer Reference Time into packet side-data (see <code class="code">AV_PKT_DATA_PRFT</code>)
|
|
for codecs that support it.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">venc_params</samp>’</dt>
|
|
<dd><p>Export video encoding parameters through frame side data (see <code class="code">AV_FRAME_DATA_VIDEO_ENC_PARAMS</code>)
|
|
for codecs that support it. At present, those are H.264 and VP9.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">film_grain</samp>’</dt>
|
|
<dd><p>Export film grain parameters through frame side data (see <code class="code">AV_FRAME_DATA_FILM_GRAIN_PARAMS</code>).
|
|
Supported at present by AV1 decoders.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">threads <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Set the number of threads to be used, in case the selected codec
|
|
implementation supports multi-threading.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">auto, 0</samp>’</dt>
|
|
<dd><p>automatically select the number of threads to set
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>Default value is ‘<samp class="samp">auto</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">dc <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set intra_dc_precision.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">nssew <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set nsse weight.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">skip_top <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Set number of macroblock rows at the top which are skipped.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">skip_bottom <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Set number of macroblock rows at the bottom which are skipped.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd>
|
|
<p>Set encoder codec profile. Default value is ‘<samp class="samp">unknown</samp>’. Encoder specific
|
|
profiles are documented in the relevant encoder documentation.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">level <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">lowres <var class="var">integer</var> (<em class="emph">decoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Decode at 1= 1/2, 2=1/4, 3=1/8 resolutions.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mblmin <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set min macroblock lagrange factor (VBR).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mblmax <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set max macroblock lagrange factor (VBR).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">skip_loop_filter <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dt><samp class="option">skip_idct <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dt><samp class="option">skip_frame <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd>
|
|
<p>Make decoder discard processing depending on the frame type selected
|
|
by the option value.
|
|
</p>
|
|
<p><samp class="option">skip_loop_filter</samp> skips frame loop filtering, <samp class="option">skip_idct</samp>
|
|
skips frame IDCT/dequantization, <samp class="option">skip_frame</samp> skips decoding.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">none</samp>’</dt>
|
|
<dd><p>Discard no frame.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">default</samp>’</dt>
|
|
<dd><p>Discard useless frames like 0-sized frames.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">noref</samp>’</dt>
|
|
<dd><p>Discard all non-reference frames.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">bidir</samp>’</dt>
|
|
<dd><p>Discard all bidirectional frames.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">nokey</samp>’</dt>
|
|
<dd><p>Discard all frames excepts keyframes.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">nointra</samp>’</dt>
|
|
<dd><p>Discard all frames except I frames.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">all</samp>’</dt>
|
|
<dd><p>Discard all frames.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>Default value is ‘<samp class="samp">default</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bidir_refine <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Refine the two motion vectors used in bidirectional macroblocks.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">keyint_min <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set minimum interval between IDR-frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">refs <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Set reference frames to consider for motion compensation.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">trellis <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dd><p>Set rate-distortion optimal quantization.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mv0_threshold <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dt><samp class="option">compression_level <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt>
|
|
<dt><samp class="option">bits_per_raw_sample <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">channel_layout <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt>
|
|
<dd>
|
|
<p>Possible values:
|
|
</p></dd>
|
|
<dt><samp class="option">request_channel_layout <var class="var">integer</var> (<em class="emph">decoding,audio</em>)</samp></dt>
|
|
<dd>
|
|
<p>Possible values:
|
|
</p></dd>
|
|
<dt><samp class="option">rc_max_vbv_use <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dt><samp class="option">rc_min_vbv_use <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dt><samp class="option">color_primaries <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">bt709</samp>’</dt>
|
|
<dd><p>BT.709
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt470m</samp>’</dt>
|
|
<dd><p>BT.470 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt470bg</samp>’</dt>
|
|
<dd><p>BT.470 BG
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte170m</samp>’</dt>
|
|
<dd><p>SMPTE 170 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte240m</samp>’</dt>
|
|
<dd><p>SMPTE 240 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">film</samp>’</dt>
|
|
<dd><p>Film
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt2020</samp>’</dt>
|
|
<dd><p>BT.2020
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte428</samp>’</dt>
|
|
<dt>‘<samp class="samp">smpte428_1</samp>’</dt>
|
|
<dd><p>SMPTE ST 428-1
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte431</samp>’</dt>
|
|
<dd><p>SMPTE 431-2
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte432</samp>’</dt>
|
|
<dd><p>SMPTE 432-1
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">jedec-p22</samp>’</dt>
|
|
<dd><p>JEDEC P22
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">color_trc <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">bt709</samp>’</dt>
|
|
<dd><p>BT.709
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">gamma22</samp>’</dt>
|
|
<dd><p>BT.470 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">gamma28</samp>’</dt>
|
|
<dd><p>BT.470 BG
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte170m</samp>’</dt>
|
|
<dd><p>SMPTE 170 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte240m</samp>’</dt>
|
|
<dd><p>SMPTE 240 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">linear</samp>’</dt>
|
|
<dd><p>Linear
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">log</samp>’</dt>
|
|
<dt>‘<samp class="samp">log100</samp>’</dt>
|
|
<dd><p>Log
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">log_sqrt</samp>’</dt>
|
|
<dt>‘<samp class="samp">log316</samp>’</dt>
|
|
<dd><p>Log square root
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">iec61966_2_4</samp>’</dt>
|
|
<dt>‘<samp class="samp">iec61966-2-4</samp>’</dt>
|
|
<dd><p>IEC 61966-2-4
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt1361</samp>’</dt>
|
|
<dt>‘<samp class="samp">bt1361e</samp>’</dt>
|
|
<dd><p>BT.1361
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">iec61966_2_1</samp>’</dt>
|
|
<dt>‘<samp class="samp">iec61966-2-1</samp>’</dt>
|
|
<dd><p>IEC 61966-2-1
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt2020_10</samp>’</dt>
|
|
<dt>‘<samp class="samp">bt2020_10bit</samp>’</dt>
|
|
<dd><p>BT.2020 - 10 bit
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt2020_12</samp>’</dt>
|
|
<dt>‘<samp class="samp">bt2020_12bit</samp>’</dt>
|
|
<dd><p>BT.2020 - 12 bit
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte2084</samp>’</dt>
|
|
<dd><p>SMPTE ST 2084
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte428</samp>’</dt>
|
|
<dt>‘<samp class="samp">smpte428_1</samp>’</dt>
|
|
<dd><p>SMPTE ST 428-1
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">arib-std-b67</samp>’</dt>
|
|
<dd><p>ARIB STD-B67
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">colorspace <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">rgb</samp>’</dt>
|
|
<dd><p>RGB
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt709</samp>’</dt>
|
|
<dd><p>BT.709
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">fcc</samp>’</dt>
|
|
<dd><p>FCC
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt470bg</samp>’</dt>
|
|
<dd><p>BT.470 BG
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte170m</samp>’</dt>
|
|
<dd><p>SMPTE 170 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte240m</samp>’</dt>
|
|
<dd><p>SMPTE 240 M
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ycocg</samp>’</dt>
|
|
<dd><p>YCOCG
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt2020nc</samp>’</dt>
|
|
<dt>‘<samp class="samp">bt2020_ncl</samp>’</dt>
|
|
<dd><p>BT.2020 NCL
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt2020c</samp>’</dt>
|
|
<dt>‘<samp class="samp">bt2020_cl</samp>’</dt>
|
|
<dd><p>BT.2020 CL
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smpte2085</samp>’</dt>
|
|
<dd><p>SMPTE 2085
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">chroma-derived-nc</samp>’</dt>
|
|
<dd><p>Chroma-derived NCL
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">chroma-derived-c</samp>’</dt>
|
|
<dd><p>Chroma-derived CL
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ictcp</samp>’</dt>
|
|
<dd><p>ICtCp
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">color_range <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>If used as input parameter, it serves as a hint to the decoder, which
|
|
color_range the input has.
|
|
Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">tv</samp>’</dt>
|
|
<dt>‘<samp class="samp">mpeg</samp>’</dt>
|
|
<dd><p>MPEG (219*2^(n-8))
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">pc</samp>’</dt>
|
|
<dt>‘<samp class="samp">jpeg</samp>’</dt>
|
|
<dd><p>JPEG (2^n-1)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">chroma_sample_location <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">left</samp>’</dt>
|
|
<dt>‘<samp class="samp">center</samp>’</dt>
|
|
<dt>‘<samp class="samp">topleft</samp>’</dt>
|
|
<dt>‘<samp class="samp">top</samp>’</dt>
|
|
<dt>‘<samp class="samp">bottomleft</samp>’</dt>
|
|
<dt>‘<samp class="samp">bottom</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">log_level_offset <var class="var">integer</var></samp></dt>
|
|
<dd><p>Set the log level offset.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">slices <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt>
|
|
<dd><p>Number of slices, used in parallelized encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">thread_type <var class="var">flags</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Select which multithreading methods to use.
|
|
</p>
|
|
<p>Use of ‘<samp class="samp">frame</samp>’ will increase decoding delay by one frame per
|
|
thread, so clients which cannot provide future frames should not use
|
|
it.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">slice</samp>’</dt>
|
|
<dd><p>Decode more than one part of a single frame at once.
|
|
</p>
|
|
<p>Multithreading using slices works only when the video was encoded with
|
|
slices.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">frame</samp>’</dt>
|
|
<dd><p>Decode more than one frame at once.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>Default value is ‘<samp class="samp">slice+frame</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">audio_service_type <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt>
|
|
<dd><p>Set audio service type.
|
|
</p>
|
|
<p>Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">ma</samp>’</dt>
|
|
<dd><p>Main Audio Service
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ef</samp>’</dt>
|
|
<dd><p>Effects
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vi</samp>’</dt>
|
|
<dd><p>Visually Impaired
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">hi</samp>’</dt>
|
|
<dd><p>Hearing Impaired
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">di</samp>’</dt>
|
|
<dd><p>Dialogue
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">co</samp>’</dt>
|
|
<dd><p>Commentary
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">em</samp>’</dt>
|
|
<dd><p>Emergency
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vo</samp>’</dt>
|
|
<dd><p>Voice Over
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ka</samp>’</dt>
|
|
<dd><p>Karaoke
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">request_sample_fmt <var class="var">sample_fmt</var> (<em class="emph">decoding,audio</em>)</samp></dt>
|
|
<dd><p>Set sample format audio decoders should prefer. Default value is
|
|
<code class="code">none</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">pkt_timebase <var class="var">rational number</var></samp></dt>
|
|
<dt><samp class="option">sub_charenc <var class="var">encoding</var> (<em class="emph">decoding,subtitles</em>)</samp></dt>
|
|
<dd><p>Set the input subtitles character encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">field_order <var class="var">field_order</var> (<em class="emph">video</em>)</samp></dt>
|
|
<dd><p>Set/override the field order of the video.
|
|
Possible values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">progressive</samp>’</dt>
|
|
<dd><p>Progressive video
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">tt</samp>’</dt>
|
|
<dd><p>Interlaced video, top field coded and displayed first
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bb</samp>’</dt>
|
|
<dd><p>Interlaced video, bottom field coded and displayed first
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">tb</samp>’</dt>
|
|
<dd><p>Interlaced video, top coded first, bottom displayed first
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">bt</samp>’</dt>
|
|
<dd><p>Interlaced video, bottom coded first, top displayed first
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">skip_alpha <var class="var">bool</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Set to 1 to disable processing alpha (transparency). This works like the
|
|
‘<samp class="samp">gray</samp>’ flag in the <samp class="option">flags</samp> option which skips chroma information
|
|
instead of alpha. Default is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">codec_whitelist <var class="var">list</var> (<em class="emph">input</em>)</samp></dt>
|
|
<dd><p>"," separated list of allowed decoders. By default all are allowed.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">dump_separator <var class="var">string</var> (<em class="emph">input</em>)</samp></dt>
|
|
<dd><p>Separator used to separate the fields printed on the command line about the
|
|
Stream parameters.
|
|
For example, to separate the fields with newlines and indentation:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffprobe -dump_separator "
|
|
" -i ~/videos/matrixbench_mpeg2.mpg
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><samp class="option">max_pixels <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt>
|
|
<dd><p>Maximum number of pixels per image. This value can be used to avoid out of
|
|
memory failures due to large images.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">apply_cropping <var class="var">bool</var> (<em class="emph">decoding,video</em>)</samp></dt>
|
|
<dd><p>Enable cropping if cropping parameters are multiples of the required
|
|
alignment for the left and top parameters. If the alignment is not met the
|
|
cropping will be partially applied to maintain alignment.
|
|
Default is 1 (enabled).
|
|
Note: The required alignment depends on if <code class="code">AV_CODEC_FLAG_UNALIGNED</code> is set and the
|
|
CPU. <code class="code">AV_CODEC_FLAG_UNALIGNED</code> cannot be changed from the command line. Also hardware
|
|
decoders will not apply left/top Cropping.
|
|
</p>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
|
|
</div>
|
|
<div class="chapter-level-extent" id="Decoders">
|
|
<h2 class="chapter">3 Decoders</h2>
|
|
|
|
<p>Decoders are configured elements in FFmpeg which allow the decoding of
|
|
multimedia streams.
|
|
</p>
|
|
<p>When you configure your FFmpeg build, all the supported native decoders
|
|
are enabled by default. Decoders requiring an external library must be enabled
|
|
manually via the corresponding <code class="code">--enable-lib</code> option. You can list all
|
|
available decoders using the configure option <code class="code">--list-decoders</code>.
|
|
</p>
|
|
<p>You can disable all the decoders with the configure option
|
|
<code class="code">--disable-decoders</code> and selectively enable / disable single decoders
|
|
with the options <code class="code">--enable-decoder=<var class="var">DECODER</var></code> /
|
|
<code class="code">--disable-decoder=<var class="var">DECODER</var></code>.
|
|
</p>
|
|
<p>The option <code class="code">-decoders</code> of the ff* tools will display the list of
|
|
enabled decoders.
|
|
</p>
|
|
|
|
</div>
|
|
<div class="chapter-level-extent" id="Video-Decoders">
|
|
<h2 class="chapter">4 Video Decoders</h2>
|
|
|
|
<p>A description of some of the currently available video decoders
|
|
follows.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#av1" accesskey="1">av1</a></li>
|
|
<li><a href="#rawvideo" accesskey="2">rawvideo</a></li>
|
|
<li><a href="#libdav1d" accesskey="3">libdav1d</a></li>
|
|
<li><a href="#libdavs2" accesskey="4">libdavs2</a></li>
|
|
<li><a href="#libuavs3d" accesskey="5">libuavs3d</a></li>
|
|
<li><a href="#QSV-Decoders" accesskey="6">QSV Decoders</a></li>
|
|
<li><a href="#v210" accesskey="7">v210</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="av1">
|
|
<h3 class="section">4.1 av1</h3>
|
|
|
|
<p>AOMedia Video 1 (AV1) decoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options">
|
|
<h4 class="subsection">4.1.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">operating_point</samp></dt>
|
|
<dd><p>Select an operating point of a scalable AV1 bitstream (0 - 31). Default is 0.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="rawvideo">
|
|
<h3 class="section">4.2 rawvideo</h3>
|
|
|
|
<p>Raw video decoder.
|
|
</p>
|
|
<p>This decoder decodes rawvideo streams.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-1" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-1">
|
|
<h4 class="subsection">4.2.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">top <var class="var">top_field_first</var></samp></dt>
|
|
<dd><p>Specify the assumed field type of the input video.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">-1</samp></dt>
|
|
<dd><p>the video is assumed to be progressive (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dd><p>bottom-field-first is assumed
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dd><p>top-field-first is assumed
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libdav1d">
|
|
<h3 class="section">4.3 libdav1d</h3>
|
|
|
|
<p>dav1d AV1 decoder.
|
|
</p>
|
|
<p>libdav1d allows libavcodec to decode the AOMedia Video 1 (AV1) codec.
|
|
Requires the presence of the libdav1d headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libdav1d</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-2" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-2">
|
|
<h4 class="subsection">4.3.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libdav1d wrapper.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">framethreads</samp></dt>
|
|
<dd><p>Set amount of frame threads to use during decoding. The default value is 0 (autodetect).
|
|
This option is deprecated for libdav1d >= 1.0 and will be removed in the future. Use the
|
|
option <code class="code">max_frame_delay</code> and the global option <code class="code">threads</code> instead.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tilethreads</samp></dt>
|
|
<dd><p>Set amount of tile threads to use during decoding. The default value is 0 (autodetect).
|
|
This option is deprecated for libdav1d >= 1.0 and will be removed in the future. Use the
|
|
global option <code class="code">threads</code> instead.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_frame_delay</samp></dt>
|
|
<dd><p>Set max amount of frames the decoder may buffer internally. The default value is 0
|
|
(autodetect).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">filmgrain</samp></dt>
|
|
<dd><p>Apply film grain to the decoded video if present in the bitstream. Defaults to the
|
|
internal default of the library.
|
|
This option is deprecated and will be removed in the future. See the global option
|
|
<code class="code">export_side_data</code> to export Film Grain parameters instead of applying it.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">oppoint</samp></dt>
|
|
<dd><p>Select an operating point of a scalable AV1 bitstream (0 - 31). Defaults to the
|
|
internal default of the library.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">alllayers</samp></dt>
|
|
<dd><p>Output all spatial layers of a scalable AV1 bitstream. The default value is false.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libdavs2">
|
|
<h3 class="section">4.4 libdavs2</h3>
|
|
|
|
<p>AVS2-P2/IEEE1857.4 video decoder wrapper.
|
|
</p>
|
|
<p>This decoder allows libavcodec to decode AVS2 streams with davs2 library.
|
|
</p>
|
|
|
|
</div>
|
|
<div class="section-level-extent" id="libuavs3d">
|
|
<h3 class="section">4.5 libuavs3d</h3>
|
|
|
|
<p>AVS3-P2/IEEE1857.10 video decoder.
|
|
</p>
|
|
<p>libuavs3d allows libavcodec to decode AVS3 streams.
|
|
Requires the presence of the libuavs3d headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libuavs3d</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-3" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-3">
|
|
<h4 class="subsection">4.5.1 Options</h4>
|
|
|
|
<p>The following option is supported by the libuavs3d wrapper.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">frame_threads</samp></dt>
|
|
<dd><p>Set amount of frame threads to use during decoding. The default value is 0 (autodetect).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="QSV-Decoders">
|
|
<h3 class="section">4.6 QSV Decoders</h3>
|
|
|
|
<p>The family of Intel QuickSync Video decoders (VC1, MPEG-2, H.264, HEVC,
|
|
JPEG/MJPEG, VP8, VP9, AV1).
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Common-Options" accesskey="1">Common Options</a></li>
|
|
<li><a href="#HEVC-Options" accesskey="2">HEVC Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Common-Options">
|
|
<h4 class="subsection">4.6.1 Common Options</h4>
|
|
|
|
<p>The following options are supported by all qsv decoders.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">async_depth</var></samp></dt>
|
|
<dd><p>Internal parallelization depth, the higher the value the higher the latency.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">gpu_copy</var></samp></dt>
|
|
<dd><p>A GPU-accelerated copy between video and system memory
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">default</samp>’</dt>
|
|
<dt>‘<samp class="samp">on</samp>’</dt>
|
|
<dt>‘<samp class="samp">off</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="HEVC-Options">
|
|
<h4 class="subsection">4.6.2 HEVC Options</h4>
|
|
<p>Extra options for hevc_qsv.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">load_plugin</var></samp></dt>
|
|
<dd><p>A user plugin to load in an internal session
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">none</samp>’</dt>
|
|
<dt>‘<samp class="samp">hevc_sw</samp>’</dt>
|
|
<dt>‘<samp class="samp">hevc_hw</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">load_plugins</var></samp></dt>
|
|
<dd><p>A :-separate list of hexadecimal plugin UIDs to load in an internal session
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="v210">
|
|
<h3 class="section">4.7 v210</h3>
|
|
|
|
<p>Uncompressed 4:2:2 10-bit decoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-4" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-4">
|
|
<h4 class="subsection">4.7.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">custom_stride</samp></dt>
|
|
<dd><p>Set the line size of the v210 data in bytes. The default value is 0
|
|
(autodetect). You can use the special -1 value for a strideless v210 as seen in
|
|
BOXX files.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Audio-Decoders">
|
|
<h2 class="chapter">5 Audio Decoders</h2>
|
|
|
|
<p>A description of some of the currently available audio decoders
|
|
follows.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#ac3" accesskey="1">ac3</a></li>
|
|
<li><a href="#flac-1" accesskey="2">flac</a></li>
|
|
<li><a href="#ffwavesynth" accesskey="3">ffwavesynth</a></li>
|
|
<li><a href="#libcelt" accesskey="4">libcelt</a></li>
|
|
<li><a href="#libgsm" accesskey="5">libgsm</a></li>
|
|
<li><a href="#libilbc" accesskey="6">libilbc</a></li>
|
|
<li><a href="#libopencore_002damrnb" accesskey="7">libopencore-amrnb</a></li>
|
|
<li><a href="#libopencore_002damrwb" accesskey="8">libopencore-amrwb</a></li>
|
|
<li><a href="#libopus" accesskey="9">libopus</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="ac3">
|
|
<h3 class="section">5.1 ac3</h3>
|
|
|
|
<p>AC-3 audio decoder.
|
|
</p>
|
|
<p>This decoder implements part of ATSC A/52:2010 and ETSI TS 102 366, as well as
|
|
the undocumented RealAudio 3 (a.k.a. dnet).
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#AC_002d3-Decoder-Options" accesskey="1">AC-3 Decoder Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="AC_002d3-Decoder-Options">
|
|
<h4 class="subsection">5.1.1 AC-3 Decoder Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-drc_scale <var class="var">value</var></samp></dt>
|
|
<dd><p>Dynamic Range Scale Factor. The factor to apply to dynamic range values
|
|
from the AC-3 stream. This factor is applied exponentially. The default value is 1.
|
|
There are 3 notable scale factor ranges:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">drc_scale == 0</samp></dt>
|
|
<dd><p>DRC disabled. Produces full range audio.
|
|
</p></dd>
|
|
<dt><samp class="option">0 < drc_scale <= 1</samp></dt>
|
|
<dd><p>DRC enabled. Applies a fraction of the stream DRC value.
|
|
Audio reproduction is between full range and full compression.
|
|
</p></dd>
|
|
<dt><samp class="option">drc_scale > 1</samp></dt>
|
|
<dd><p>DRC enabled. Applies drc_scale asymmetrically.
|
|
Loud sounds are fully compressed. Soft sounds are enhanced.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="flac-1">
|
|
<h3 class="section">5.2 flac</h3>
|
|
|
|
<p>FLAC audio decoder.
|
|
</p>
|
|
<p>This decoder aims to implement the complete FLAC specification from Xiph.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#FLAC-Decoder-options" accesskey="1">FLAC Decoder options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="FLAC-Decoder-options">
|
|
<h4 class="subsection">5.2.1 FLAC Decoder options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-use_buggy_lpc</samp></dt>
|
|
<dd><p>The lavc FLAC encoder used to produce buggy streams with high lpc values
|
|
(like the default value). This option makes it possible to decode such streams
|
|
correctly by using lavc’s old buggy lpc logic for decoding.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="ffwavesynth">
|
|
<h3 class="section">5.3 ffwavesynth</h3>
|
|
|
|
<p>Internal wave synthesizer.
|
|
</p>
|
|
<p>This decoder generates wave patterns according to predefined sequences. Its
|
|
use is purely internal and the format of the data it accepts is not publicly
|
|
documented.
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="libcelt">
|
|
<h3 class="section">5.4 libcelt</h3>
|
|
|
|
<p>libcelt decoder wrapper.
|
|
</p>
|
|
<p>libcelt allows libavcodec to decode the Xiph CELT ultra-low delay audio codec.
|
|
Requires the presence of the libcelt headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libcelt</code>.
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="libgsm">
|
|
<h3 class="section">5.5 libgsm</h3>
|
|
|
|
<p>libgsm decoder wrapper.
|
|
</p>
|
|
<p>libgsm allows libavcodec to decode the GSM full rate audio codec. Requires
|
|
the presence of the libgsm headers and library during configuration. You need
|
|
to explicitly configure the build with <code class="code">--enable-libgsm</code>.
|
|
</p>
|
|
<p>This decoder supports both the ordinary GSM and the Microsoft variant.
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="libilbc">
|
|
<h3 class="section">5.6 libilbc</h3>
|
|
|
|
<p>libilbc decoder wrapper.
|
|
</p>
|
|
<p>libilbc allows libavcodec to decode the Internet Low Bitrate Codec (iLBC)
|
|
audio codec. Requires the presence of the libilbc headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libilbc</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-5" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-5">
|
|
<h4 class="subsection">5.6.1 Options</h4>
|
|
|
|
<p>The following option is supported by the libilbc wrapper.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">enhance</samp></dt>
|
|
<dd>
|
|
<p>Enable the enhancement of the decoded audio when set to 1. The default
|
|
value is 0 (disabled).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libopencore_002damrnb">
|
|
<h3 class="section">5.7 libopencore-amrnb</h3>
|
|
|
|
<p>libopencore-amrnb decoder wrapper.
|
|
</p>
|
|
<p>libopencore-amrnb allows libavcodec to decode the Adaptive Multi-Rate
|
|
Narrowband audio codec. Using it requires the presence of the
|
|
libopencore-amrnb headers and library during configuration. You need to
|
|
explicitly configure the build with <code class="code">--enable-libopencore-amrnb</code>.
|
|
</p>
|
|
<p>An FFmpeg native decoder for AMR-NB exists, so users can decode AMR-NB
|
|
without this library.
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="libopencore_002damrwb">
|
|
<h3 class="section">5.8 libopencore-amrwb</h3>
|
|
|
|
<p>libopencore-amrwb decoder wrapper.
|
|
</p>
|
|
<p>libopencore-amrwb allows libavcodec to decode the Adaptive Multi-Rate
|
|
Wideband audio codec. Using it requires the presence of the
|
|
libopencore-amrwb headers and library during configuration. You need to
|
|
explicitly configure the build with <code class="code">--enable-libopencore-amrwb</code>.
|
|
</p>
|
|
<p>An FFmpeg native decoder for AMR-WB exists, so users can decode AMR-WB
|
|
without this library.
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="libopus">
|
|
<h3 class="section">5.9 libopus</h3>
|
|
|
|
<p>libopus decoder wrapper.
|
|
</p>
|
|
<p>libopus allows libavcodec to decode the Opus Interactive Audio Codec.
|
|
Requires the presence of the libopus headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libopus</code>.
|
|
</p>
|
|
<p>An FFmpeg native decoder for Opus exists, so users can decode Opus
|
|
without this library.
|
|
</p>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Subtitles-Decoders">
|
|
<h2 class="chapter">6 Subtitles Decoders</h2>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="#libaribb24" accesskey="1">libaribb24</a></li>
|
|
<li><a href="#libaribcaption" accesskey="2">libaribcaption</a></li>
|
|
<li><a href="#dvbsub" accesskey="3">dvbsub</a></li>
|
|
<li><a href="#dvdsub" accesskey="4">dvdsub</a></li>
|
|
<li><a href="#libzvbi_002dteletext" accesskey="5">libzvbi-teletext</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="libaribb24">
|
|
<h3 class="section">6.1 libaribb24</h3>
|
|
|
|
<p>ARIB STD-B24 caption decoder.
|
|
</p>
|
|
<p>Implements profiles A and C of the ARIB STD-B24 standard.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#libaribb24-Decoder-Options" accesskey="1">libaribb24 Decoder Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="libaribb24-Decoder-Options">
|
|
<h4 class="subsection">6.1.1 libaribb24 Decoder Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-aribb24-base-path <var class="var">path</var></samp></dt>
|
|
<dd><p>Sets the base path for the libaribb24 library. This is utilized for reading of
|
|
configuration files (for custom unicode conversions), and for dumping of
|
|
non-text symbols as images under that location.
|
|
</p>
|
|
<p>Unset by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-aribb24-skip-ruby-text <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Tells the decoder wrapper to skip text blocks that contain half-height ruby
|
|
text.
|
|
</p>
|
|
<p>Enabled by default.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libaribcaption">
|
|
<h3 class="section">6.2 libaribcaption</h3>
|
|
|
|
<p>Yet another ARIB STD-B24 caption decoder using external <em class="dfn">libaribcaption</em>
|
|
library.
|
|
</p>
|
|
<p>Implements profiles A and C of the Japanse ARIB STD-B24 standard,
|
|
Brazilian ABNT NBR 15606-1, and Philippines version of ISDB-T.
|
|
</p>
|
|
<p>Requires the presence of the libaribcaption headers and library
|
|
(<a class="url" href="https://github.com/xqq/libaribcaption">https://github.com/xqq/libaribcaption</a>) during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libaribcaption</code>.
|
|
If both <em class="dfn">libaribb24</em> and <em class="dfn">libaribcaption</em> are enabled, <em class="dfn">libaribcaption</em>
|
|
decoder precedes.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#libaribcaption-Decoder-Options" accesskey="1">libaribcaption Decoder Options</a></li>
|
|
<li><a href="#libaribcaption-decoder-usage-examples" accesskey="2">libaribcaption decoder usage examples</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="libaribcaption-Decoder-Options">
|
|
<h4 class="subsection">6.2.1 libaribcaption Decoder Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-sub_type <var class="var">subtitle_type</var></samp></dt>
|
|
<dd><p>Specifies the format of the decoded subtitles.
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">bitmap</samp>’</dt>
|
|
<dd><p>Graphical image.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">ass</samp>’</dt>
|
|
<dd><p>ASS formatted text.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">text</samp>’</dt>
|
|
<dd><p>Simple text based output without formatting.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>The default is <em class="dfn">ass</em> as same as <em class="dfn">libaribb24</em> decoder.
|
|
Some present players (e.g., <em class="dfn">mpv</em>) expect ASS format for ARIB caption.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-caption_encoding <var class="var">encoding_scheme</var></samp></dt>
|
|
<dd><p>Specifies the encoding scheme of input subtitle text.
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dd><p>Automatically detect text encoding.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">jis</samp>’</dt>
|
|
<dd><p>8bit-char JIS encoding defined in ARIB STD B24.
|
|
This encoding used in Japan for ISDB captions.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">utf8</samp>’</dt>
|
|
<dd><p>UTF-8 encoding defined in ARIB STD B24.
|
|
This encoding is used in Philippines for ISDB-T captions.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">latin</samp>’</dt>
|
|
<dd><p>Latin character encoding defined in ABNT NBR 15606-1.
|
|
This encoding is used in South America for SBTVD / ISDB-Tb captions.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>The default is <em class="dfn">ass</em> as same as <em class="dfn">libaribb24</em> decoder.
|
|
Some present players (e.g., <em class="dfn">mpv</em>) expect ASS format for ARIB caption.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-font <var class="var">font_name[,font_name2,...]</var></samp></dt>
|
|
<dd><p>Specify comma-separated list of font family names to be used for <em class="dfn">bitmap</em>
|
|
or <em class="dfn">ass</em> type subtitle rendering.
|
|
Only first font name is used for <em class="dfn">ass</em> type subtitle.
|
|
</p>
|
|
<p>If not specified, use internaly defined default font family.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-ass_single_rect <var class="var">boolean</var></samp></dt>
|
|
<dd><p>ARIB STD-B24 specifies that some captions may be displayed at different
|
|
positions at a time (multi-rectangle subtitle).
|
|
Since some players (e.g., old <em class="dfn">mpv</em>) can’t handle multiple ASS rectangles
|
|
in a single AVSubtitle, or multiple ASS rectangles of indeterminate duration
|
|
with the same start timestamp, this option can change the behavior so that
|
|
all the texts are displayed in a single ASS rectangle.
|
|
</p>
|
|
<p>The default is <var class="var">false</var>.
|
|
</p>
|
|
<p>If your player cannot handle AVSubtitles with multiple ASS rectangles properly,
|
|
set this option to <var class="var">true</var> or define <code class="env">ASS_SINGLE_RECT=1</code> to change
|
|
default behavior at compilation.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-replace_fullwidth_ascii <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Specify whether to replace MSZ (Middle Size, half width) fullwidth
|
|
alphanumerics with halfwidth alphanumerics.
|
|
</p>
|
|
<p>The default is <var class="var">true</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-force_outline_text <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Specify whether always render outline text for all characters regardless of
|
|
the indication by charactor style.
|
|
</p>
|
|
<p>The default is <var class="var">false</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-outline_width <var class="var">number</var> (0.0 - 3.0)</samp></dt>
|
|
<dd><p>Specify width for outline text, in dots (relative).
|
|
</p>
|
|
<p>The default is <var class="var">1.5</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-ignore_background <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Specify whether to ignore background color rendering.
|
|
</p>
|
|
<p>The default is <var class="var">false</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-ignore_ruby <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Specify whether to ignore rendering for ruby-like (furigana) characters.
|
|
</p>
|
|
<p>The default is <var class="var">false</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-replace_drcs <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Specify whether to render replaced DRCS characters as Unicode characters.
|
|
</p>
|
|
<p>The default is <var class="var">true</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-canvas_size <var class="var">image_size</var></samp></dt>
|
|
<dd><p>Specify the resolution of the canvas to render subtitles to; usually, this
|
|
should be frame size of input video.
|
|
This only applies when <code class="code">-subtitle_type</code> is set to <var class="var">bitmap</var>.
|
|
</p>
|
|
<p>The libaribcaption decoder assumes input frame size for bitmap rendering as below:
|
|
</p><ol class="enumerate">
|
|
<li> PROFILE_A : 1440 x 1080 with SAR (PAR) 4:3
|
|
</li><li> PROFILE_C : 320 x 180 with SAR (PAR) 1:1
|
|
</li></ol>
|
|
|
|
<p>If actual frame size of input video does not match above assumption,
|
|
the rendered captions may be distorted.
|
|
To make the captions undistorted, add <code class="code">-canvas_size</code> option to specify
|
|
actual input video size.
|
|
</p>
|
|
<p>Note that the <code class="code">-canvas_size</code> option is not required for video with
|
|
different size but same aspect ratio.
|
|
In such cases, the caption will be stretched or shrunk to actual video size
|
|
if <code class="code">-canvas_size</code> option is not specified.
|
|
If <code class="code">-canvas_size</code> option is specified with different size,
|
|
the caption will be stretched or shrunk as specified size with calculated SAR.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="libaribcaption-decoder-usage-examples">
|
|
<h4 class="subsection">6.2.2 libaribcaption decoder usage examples</h4>
|
|
|
|
<p>Display MPEG-TS file with ARIB subtitle by <code class="code">ffplay</code> tool:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffplay -sub_type bitmap MPEG.TS
|
|
</pre></div>
|
|
|
|
<p>Display MPEG-TS file with input frame size 1920x1080 by <code class="code">ffplay</code> tool:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffplay -sub_type bitmap -canvas_size 1920x1080 MPEG.TS
|
|
</pre></div>
|
|
|
|
<p>Embed ARIB subtitle in transcoded video:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffmpeg -sub_type bitmap -i src.m2t -filter_complex "[0:v][0:s]overlay" -vcodec h264 dest.mp4
|
|
</pre></div>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="dvbsub">
|
|
<h3 class="section">6.3 dvbsub</h3>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-6" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-6">
|
|
<h4 class="subsection">6.3.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">compute_clut</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt><samp class="option">-2</samp></dt>
|
|
<dd><p>Compute clut once if no matching CLUT is in the stream.
|
|
</p></dd>
|
|
<dt><samp class="option">-1</samp></dt>
|
|
<dd><p>Compute clut if no matching CLUT is in the stream.
|
|
</p></dd>
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dd><p>Never compute CLUT
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dd><p>Always compute CLUT and override the one provided in the stream.
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
<dt><samp class="option">dvb_substream</samp></dt>
|
|
<dd><p>Selects the dvb substream, or all substreams if -1 which is default.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="dvdsub">
|
|
<h3 class="section">6.4 dvdsub</h3>
|
|
|
|
<p>This codec decodes the bitmap subtitles used in DVDs; the same subtitles can
|
|
also be found in VobSub file pairs and in some Matroska files.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-7" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-7">
|
|
<h4 class="subsection">6.4.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">palette</samp></dt>
|
|
<dd><p>Specify the global palette used by the bitmaps. When stored in VobSub, the
|
|
palette is normally specified in the index file; in Matroska, the palette is
|
|
stored in the codec extra-data in the same format as in VobSub. In DVDs, the
|
|
palette is stored in the IFO file, and therefore not available when reading
|
|
from dumped VOB files.
|
|
</p>
|
|
<p>The format for this option is a string containing 16 24-bits hexadecimal
|
|
numbers (without 0x prefix) separated by commas, for example <code class="code">0d00ee,
|
|
ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1,
|
|
7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ifo_palette</samp></dt>
|
|
<dd><p>Specify the IFO file from which the global palette is obtained.
|
|
(experimental)
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">forced_subs_only</samp></dt>
|
|
<dd><p>Only decode subtitle entries marked as forced. Some titles have forced
|
|
and non-forced subtitles in the same track. Setting this flag to <code class="code">1</code>
|
|
will only keep the forced subtitles. Default value is <code class="code">0</code>.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libzvbi_002dteletext">
|
|
<h3 class="section">6.5 libzvbi-teletext</h3>
|
|
|
|
<p>Libzvbi allows libavcodec to decode DVB teletext pages and DVB teletext
|
|
subtitles. Requires the presence of the libzvbi headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libzvbi</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-8" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-8">
|
|
<h4 class="subsection">6.5.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">txt_page</samp></dt>
|
|
<dd><p>List of teletext page numbers to decode. Pages that do not match the specified
|
|
list are dropped. You may use the special <code class="code">*</code> string to match all pages,
|
|
or <code class="code">subtitle</code> to match all subtitle pages.
|
|
Default value is *.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_default_region</samp></dt>
|
|
<dd><p>Set default character set used for decoding, a value between 0 and 87 (see
|
|
ETS 300 706, Section 15, Table 32). Default value is -1, which does not
|
|
override the libzvbi default. This option is needed for some legacy level 1.0
|
|
transmissions which cannot signal the proper charset.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_chop_top</samp></dt>
|
|
<dd><p>Discards the top teletext line. Default value is 1.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_format</samp></dt>
|
|
<dd><p>Specifies the format of the decoded subtitles.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">bitmap</samp></dt>
|
|
<dd><p>The default format, you should use this for teletext pages, because certain
|
|
graphics and colors cannot be expressed in simple text or even ASS.
|
|
</p></dd>
|
|
<dt><samp class="option">text</samp></dt>
|
|
<dd><p>Simple text based output without formatting.
|
|
</p></dd>
|
|
<dt><samp class="option">ass</samp></dt>
|
|
<dd><p>Formatted ASS output, subtitle pages and teletext pages are returned in
|
|
different styles, subtitle pages are stripped down to text, but an effort is
|
|
made to keep the text alignment and the formatting.
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
<dt><samp class="option">txt_left</samp></dt>
|
|
<dd><p>X offset of generated bitmaps, default is 0.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_top</samp></dt>
|
|
<dd><p>Y offset of generated bitmaps, default is 0.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_chop_spaces</samp></dt>
|
|
<dd><p>Chops leading and trailing spaces and removes empty lines from the generated
|
|
text. This option is useful for teletext based subtitles where empty spaces may
|
|
be present at the start or at the end of the lines or empty lines may be
|
|
present between the subtitle lines because of double-sized teletext characters.
|
|
Default value is 1.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_duration</samp></dt>
|
|
<dd><p>Sets the display duration of the decoded teletext pages or subtitles in
|
|
milliseconds. Default value is -1 which means infinity or until the next
|
|
subtitle event comes.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_transparent</samp></dt>
|
|
<dd><p>Force transparent background of the generated teletext bitmaps. Default value
|
|
is 0 which means an opaque background.
|
|
</p></dd>
|
|
<dt><samp class="option">txt_opacity</samp></dt>
|
|
<dd><p>Sets the opacity (0-255) of the teletext background. If
|
|
<samp class="option">txt_transparent</samp> is not set, it only affects characters between a start
|
|
box and an end box, typically subtitles. Default value is 0 if
|
|
<samp class="option">txt_transparent</samp> is set, 255 otherwise.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Encoders">
|
|
<h2 class="chapter">7 Encoders</h2>
|
|
|
|
<p>Encoders are configured elements in FFmpeg which allow the encoding of
|
|
multimedia streams.
|
|
</p>
|
|
<p>When you configure your FFmpeg build, all the supported native encoders
|
|
are enabled by default. Encoders requiring an external library must be enabled
|
|
manually via the corresponding <code class="code">--enable-lib</code> option. You can list all
|
|
available encoders using the configure option <code class="code">--list-encoders</code>.
|
|
</p>
|
|
<p>You can disable all the encoders with the configure option
|
|
<code class="code">--disable-encoders</code> and selectively enable / disable single encoders
|
|
with the options <code class="code">--enable-encoder=<var class="var">ENCODER</var></code> /
|
|
<code class="code">--disable-encoder=<var class="var">ENCODER</var></code>.
|
|
</p>
|
|
<p>The option <code class="code">-encoders</code> of the ff* tools will display the list of
|
|
enabled encoders.
|
|
</p>
|
|
|
|
</div>
|
|
<div class="chapter-level-extent" id="Audio-Encoders">
|
|
<h2 class="chapter">8 Audio Encoders</h2>
|
|
|
|
<p>A description of some of the currently available audio encoders
|
|
follows.
|
|
</p>
|
|
<a class="anchor" id="aacenc"></a><ul class="mini-toc">
|
|
<li><a href="#aac" accesskey="1">aac</a></li>
|
|
<li><a href="#ac3-and-ac3_005ffixed" accesskey="2">ac3 and ac3_fixed</a></li>
|
|
<li><a href="#flac-2" accesskey="3">flac</a></li>
|
|
<li><a href="#opus" accesskey="4">opus</a></li>
|
|
<li><a href="#libfdk_005faac" accesskey="5">libfdk_aac</a></li>
|
|
<li><a href="#libmp3lame-1" accesskey="6">libmp3lame</a></li>
|
|
<li><a href="#libopencore_002damrnb-1" accesskey="7">libopencore-amrnb</a></li>
|
|
<li><a href="#libopus-1" accesskey="8">libopus</a></li>
|
|
<li><a href="#libshine-1" accesskey="9">libshine</a></li>
|
|
<li><a href="#libtwolame">libtwolame</a></li>
|
|
<li><a href="#libvo_002damrwbenc">libvo-amrwbenc</a></li>
|
|
<li><a href="#libvorbis">libvorbis</a></li>
|
|
<li><a href="#mjpeg">mjpeg</a></li>
|
|
<li><a href="#wavpack">wavpack</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="aac">
|
|
<h3 class="section">8.1 aac</h3>
|
|
|
|
<p>Advanced Audio Coding (AAC) encoder.
|
|
</p>
|
|
<p>This encoder is the default AAC encoder, natively implemented into FFmpeg.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-9" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-9">
|
|
<h4 class="subsection">8.1.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bit rate in bits/s. Setting this automatically activates constant bit rate
|
|
(CBR) mode. If this option is unspecified it is set to 128kbps.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q</samp></dt>
|
|
<dd><p>Set quality for variable bit rate (VBR) mode. This option is valid only using
|
|
the <code class="command">ffmpeg</code> command-line tool. For library interface users, use
|
|
<samp class="option">global_quality</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff</samp></dt>
|
|
<dd><p>Set cutoff frequency. If unspecified will allow the encoder to dynamically
|
|
adjust the cutoff to improve clarity on low bitrates.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_coder</samp></dt>
|
|
<dd><p>Set AAC encoder coding method. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">twoloop</samp>’</dt>
|
|
<dd><p>Two loop searching (TLS) method. This is the default method.
|
|
</p>
|
|
<p>This method first sets quantizers depending on band thresholds and then tries
|
|
to find an optimal combination by adding or subtracting a specific value from
|
|
all quantizers and adjusting some individual quantizer a little. Will tune
|
|
itself based on whether <samp class="option">aac_is</samp>, <samp class="option">aac_ms</samp> and <samp class="option">aac_pns</samp>
|
|
are enabled.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">anmr</samp>’</dt>
|
|
<dd><p>Average noise to mask ratio (ANMR) trellis-based solution.
|
|
</p>
|
|
<p>This is an experimental coder which currently produces a lower quality, is more
|
|
unstable and is slower than the default twoloop coder but has potential.
|
|
Currently has no support for the <samp class="option">aac_is</samp> or <samp class="option">aac_pns</samp> options.
|
|
Not currently recommended.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">fast</samp>’</dt>
|
|
<dd><p>Constant quantizer method.
|
|
</p>
|
|
<p>Uses a cheaper version of twoloop algorithm that doesn’t try to do as many
|
|
clever adjustments. Worse with low bitrates (less than 64kbps), but is better
|
|
and much faster at higher bitrates.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">aac_ms</samp></dt>
|
|
<dd><p>Sets mid/side coding mode. The default value of "auto" will automatically use
|
|
M/S with bands which will benefit from such coding. Can be forced for all bands
|
|
using the value "enable", which is mainly useful for debugging or disabled using
|
|
"disable".
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_is</samp></dt>
|
|
<dd><p>Sets intensity stereo coding tool usage. By default, it’s enabled and will
|
|
automatically toggle IS for similar pairs of stereo bands if it’s beneficial.
|
|
Can be disabled for debugging by setting the value to "disable".
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_pns</samp></dt>
|
|
<dd><p>Uses perceptual noise substitution to replace low entropy high frequency bands
|
|
with imperceptible white noise during the decoding process. By default, it’s
|
|
enabled, but can be disabled for debugging purposes by using "disable".
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_tns</samp></dt>
|
|
<dd><p>Enables the use of a multitap FIR filter which spans through the high frequency
|
|
bands to hide quantization noise during the encoding process and is reverted
|
|
by the decoder. As well as decreasing unpleasant artifacts in the high range
|
|
this also reduces the entropy in the high bands and allows for more bits to
|
|
be used by the mid-low bands. By default it’s enabled but can be disabled for
|
|
debugging by setting the option to "disable".
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_ltp</samp></dt>
|
|
<dd><p>Enables the use of the long term prediction extension which increases coding
|
|
efficiency in very low bandwidth situations such as encoding of voice or
|
|
solo piano music by extending constant harmonic peaks in bands throughout
|
|
frames. This option is implied by profile:a aac_low and is incompatible with
|
|
aac_pred. Use in conjunction with <samp class="option">-ar</samp> to decrease the samplerate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aac_pred</samp></dt>
|
|
<dd><p>Enables the use of a more traditional style of prediction where the spectral
|
|
coefficients transmitted are replaced by the difference of the current
|
|
coefficients minus the previous "predicted" coefficients. In theory and sometimes
|
|
in practice this can improve quality for low to mid bitrate audio.
|
|
This option implies the aac_main profile and is incompatible with aac_ltp.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Sets the encoding profile, possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">aac_low</samp>’</dt>
|
|
<dd><p>The default, AAC "Low-complexity" profile. Is the most compatible and produces
|
|
decent quality.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">mpeg2_aac_low</samp>’</dt>
|
|
<dd><p>Equivalent to <code class="code">-profile:a aac_low -aac_pns 0</code>. PNS was introduced with the
|
|
MPEG4 specifications.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_ltp</samp>’</dt>
|
|
<dd><p>Long term prediction profile, is enabled by and will enable the <samp class="option">aac_ltp</samp>
|
|
option. Introduced in MPEG4.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_main</samp>’</dt>
|
|
<dd><p>Main-type prediction profile, is enabled by and will enable the <samp class="option">aac_pred</samp>
|
|
option. Introduced in MPEG2.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<p>If this option is unspecified it is set to ‘<samp class="samp">aac_low</samp>’.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="ac3-and-ac3_005ffixed">
|
|
<h3 class="section">8.2 ac3 and ac3_fixed</h3>
|
|
|
|
<p>AC-3 audio encoders.
|
|
</p>
|
|
<p>These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366, as well as
|
|
the undocumented RealAudio 3 (a.k.a. dnet).
|
|
</p>
|
|
<p>The <var class="var">ac3</var> encoder uses floating-point math, while the <var class="var">ac3_fixed</var>
|
|
encoder only uses fixed-point integer math. This does not mean that one is
|
|
always faster, just that one or the other may be better suited to a
|
|
particular system. The <var class="var">ac3_fixed</var> encoder is not the default codec for
|
|
any of the output formats, so it must be specified explicitly using the option
|
|
<code class="code">-acodec ac3_fixed</code> in order to use it.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#AC_002d3-Metadata" accesskey="1">AC-3 Metadata</a></li>
|
|
<li><a href="#Extended-Bitstream-Information" accesskey="2">Extended Bitstream Information</a></li>
|
|
<li><a href="#Other-AC_002d3-Encoding-Options" accesskey="3">Other AC-3 Encoding Options</a></li>
|
|
<li><a href="#Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options" accesskey="4">Floating-Point-Only AC-3 Encoding Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="AC_002d3-Metadata">
|
|
<h4 class="subsection">8.2.1 AC-3 Metadata</h4>
|
|
|
|
<p>The AC-3 metadata options are used to set parameters that describe the audio,
|
|
but in most cases do not affect the audio encoding itself. Some of the options
|
|
do directly affect or influence the decoding and playback of the resulting
|
|
bitstream, while others are just for informational purposes. A few of the
|
|
options will add bits to the output stream that could otherwise be used for
|
|
audio data, and will thus affect the quality of the output. Those will be
|
|
indicated accordingly with a note in the option list below.
|
|
</p>
|
|
<p>These parameters are described in detail in several publicly-available
|
|
documents.
|
|
</p><ul class="itemize mark-bullet">
|
|
<li><a class="uref" href="http://www.atsc.org/cms/standards/a_52-2010.pdf">A/52:2010 - Digital Audio Compression (AC-3) (E-AC-3) Standard</a>
|
|
</li><li><a class="uref" href="http://www.atsc.org/cms/standards/a_54a_with_corr_1.pdf">A/54 - Guide to the Use of the ATSC Digital Television Standard</a>
|
|
</li><li><a class="uref" href="http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/18_Metadata.Guide.pdf">Dolby Metadata Guide</a>
|
|
</li><li><a class="uref" href="http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/46_DDEncodingGuidelines.pdf">Dolby Digital Professional Encoding Guidelines</a>
|
|
</li></ul>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="#Metadata-Control-Options" accesskey="1">Metadata Control Options</a></li>
|
|
<li><a href="#Downmix-Levels" accesskey="2">Downmix Levels</a></li>
|
|
<li><a href="#Audio-Production-Information" accesskey="3">Audio Production Information</a></li>
|
|
<li><a href="#Other-Metadata-Options" accesskey="4">Other Metadata Options</a></li>
|
|
</ul>
|
|
<div class="subsubsection-level-extent" id="Metadata-Control-Options">
|
|
<h4 class="subsubsection">8.2.1.1 Metadata Control Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-per_frame_metadata <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Allow Per-Frame Metadata. Specifies if the encoder should check for changing
|
|
metadata for each frame.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dd><p>The metadata values set at initialization will be used for every frame in the
|
|
stream. (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dd><p>Metadata values can be changed before encoding each frame.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsubsection-level-extent" id="Downmix-Levels">
|
|
<h4 class="subsubsection">8.2.1.2 Downmix Levels</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-center_mixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Center Mix Level. The amount of gain the decoder should apply to the center
|
|
channel when downmixing to stereo. This field will only be written to the
|
|
bitstream if a center channel is present. The value is specified as a scale
|
|
factor. There are 3 valid values:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.595</samp></dt>
|
|
<dd><p>Apply -4.5dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6dB gain
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-surround_mixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Surround Mix Level. The amount of gain the decoder should apply to the surround
|
|
channel(s) when downmixing to stereo. This field will only be written to the
|
|
bitstream if one or more surround channels are present. The value is specified
|
|
as a scale factor. There are 3 valid values:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.000</samp></dt>
|
|
<dd><p>Silence Surround Channel(s)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsubsection-level-extent" id="Audio-Production-Information">
|
|
<h4 class="subsubsection">8.2.1.3 Audio Production Information</h4>
|
|
<p>Audio Production Information is optional information describing the mixing
|
|
environment. Either none or both of the fields are written to the bitstream.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">-mixing_level <var class="var">number</var></samp></dt>
|
|
<dd><p>Mixing Level. Specifies peak sound pressure level (SPL) in the production
|
|
environment when the mix was mastered. Valid values are 80 to 111, or -1 for
|
|
unknown or not indicated. The default value is -1, but that value cannot be
|
|
used if the Audio Production Information is written to the bitstream. Therefore,
|
|
if the <code class="code">room_type</code> option is not the default value, the <code class="code">mixing_level</code>
|
|
option must not be -1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-room_type <var class="var">type</var></samp></dt>
|
|
<dd><p>Room Type. Describes the equalization used during the final mixing session at
|
|
the studio or on the dubbing stage. A large room is a dubbing stage with the
|
|
industry standard X-curve equalization; a small room has flat equalization.
|
|
This field will not be written to the bitstream if both the <code class="code">mixing_level</code>
|
|
option and the <code class="code">room_type</code> option have the default values.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">notindicated</samp></dt>
|
|
<dd><p>Not Indicated (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">large</samp></dt>
|
|
<dd><p>Large Room
|
|
</p></dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dt><samp class="option">small</samp></dt>
|
|
<dd><p>Small Room
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsubsection-level-extent" id="Other-Metadata-Options">
|
|
<h4 class="subsubsection">8.2.1.4 Other Metadata Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-copyright <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Copyright Indicator. Specifies whether a copyright exists for this audio.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>No Copyright Exists (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Copyright Exists
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-dialnorm <var class="var">value</var></samp></dt>
|
|
<dd><p>Dialogue Normalization. Indicates how far the average dialogue level of the
|
|
program is below digital 100% full scale (0 dBFS). This parameter determines a
|
|
level shift during audio reproduction that sets the average volume of the
|
|
dialogue to a preset level. The goal is to match volume level between program
|
|
sources. A value of -31dB will result in no volume level change, relative to
|
|
the source volume, during audio reproduction. Valid values are whole numbers in
|
|
the range -31 to -1, with -31 being the default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-dsur_mode <var class="var">mode</var></samp></dt>
|
|
<dd><p>Dolby Surround Mode. Specifies whether the stereo signal uses Dolby Surround
|
|
(Pro Logic). This field will only be written to the bitstream if the audio
|
|
stream is stereo. Using this option does <b class="b">NOT</b> mean the encoder will actually
|
|
apply Dolby Surround processing.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">notindicated</samp></dt>
|
|
<dd><p>Not Indicated (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>Not Dolby Surround Encoded
|
|
</p></dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Dolby Surround Encoded
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-original <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Original Bit Stream Indicator. Specifies whether this audio is from the
|
|
original source and not a copy.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>Not Original Source
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Original Source (default)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="subsection-level-extent" id="Extended-Bitstream-Information">
|
|
<h4 class="subsection">8.2.2 Extended Bitstream Information</h4>
|
|
<p>The extended bitstream options are part of the Alternate Bit Stream Syntax as
|
|
specified in Annex D of the A/52:2010 standard. It is grouped into 2 parts.
|
|
If any one parameter in a group is specified, all values in that group will be
|
|
written to the bitstream. Default values are used for those that are written
|
|
but have not been specified. If the mixing levels are written, the decoder
|
|
will use these values instead of the ones specified in the <code class="code">center_mixlev</code>
|
|
and <code class="code">surround_mixlev</code> options if it supports the Alternate Bit Stream
|
|
Syntax.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Extended-Bitstream-Information-_002d-Part-1" accesskey="1">Extended Bitstream Information - Part 1</a></li>
|
|
<li><a href="#Extended-Bitstream-Information-_002d-Part-2" accesskey="2">Extended Bitstream Information - Part 2</a></li>
|
|
</ul>
|
|
<div class="subsubsection-level-extent" id="Extended-Bitstream-Information-_002d-Part-1">
|
|
<h4 class="subsubsection">8.2.2.1 Extended Bitstream Information - Part 1</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-dmix_mode <var class="var">mode</var></samp></dt>
|
|
<dd><p>Preferred Stereo Downmix Mode. Allows the user to select either Lt/Rt
|
|
(Dolby Surround) or Lo/Ro (normal stereo) as the preferred stereo downmix mode.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">notindicated</samp></dt>
|
|
<dd><p>Not Indicated (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">ltrt</samp></dt>
|
|
<dd><p>Lt/Rt Downmix Preferred
|
|
</p></dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dt><samp class="option">loro</samp></dt>
|
|
<dd><p>Lo/Ro Downmix Preferred
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-ltrt_cmixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Lt/Rt Center Mix Level. The amount of gain the decoder should apply to the
|
|
center channel when downmixing to stereo in Lt/Rt mode.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">1.414</samp></dt>
|
|
<dd><p>Apply +3dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">1.189</samp></dt>
|
|
<dd><p>Apply +1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">1.000</samp></dt>
|
|
<dd><p>Apply 0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.841</samp></dt>
|
|
<dd><p>Apply -1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.595</samp></dt>
|
|
<dd><p>Apply -4.5dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.000</samp></dt>
|
|
<dd><p>Silence Center Channel
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-ltrt_surmixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Lt/Rt Surround Mix Level. The amount of gain the decoder should apply to the
|
|
surround channel(s) when downmixing to stereo in Lt/Rt mode.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0.841</samp></dt>
|
|
<dd><p>Apply -1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.595</samp></dt>
|
|
<dd><p>Apply -4.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6.0dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.000</samp></dt>
|
|
<dd><p>Silence Surround Channel(s)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-loro_cmixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Lo/Ro Center Mix Level. The amount of gain the decoder should apply to the
|
|
center channel when downmixing to stereo in Lo/Ro mode.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">1.414</samp></dt>
|
|
<dd><p>Apply +3dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">1.189</samp></dt>
|
|
<dd><p>Apply +1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">1.000</samp></dt>
|
|
<dd><p>Apply 0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.841</samp></dt>
|
|
<dd><p>Apply -1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.595</samp></dt>
|
|
<dd><p>Apply -4.5dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.000</samp></dt>
|
|
<dd><p>Silence Center Channel
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-loro_surmixlev <var class="var">level</var></samp></dt>
|
|
<dd><p>Lo/Ro Surround Mix Level. The amount of gain the decoder should apply to the
|
|
surround channel(s) when downmixing to stereo in Lo/Ro mode.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0.841</samp></dt>
|
|
<dd><p>Apply -1.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.707</samp></dt>
|
|
<dd><p>Apply -3.0dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.595</samp></dt>
|
|
<dd><p>Apply -4.5dB gain
|
|
</p></dd>
|
|
<dt><samp class="option">0.500</samp></dt>
|
|
<dd><p>Apply -6.0dB gain (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0.000</samp></dt>
|
|
<dd><p>Silence Surround Channel(s)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsubsection-level-extent" id="Extended-Bitstream-Information-_002d-Part-2">
|
|
<h4 class="subsubsection">8.2.2.2 Extended Bitstream Information - Part 2</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-dsurex_mode <var class="var">mode</var></samp></dt>
|
|
<dd><p>Dolby Surround EX Mode. Indicates whether the stream uses Dolby Surround EX
|
|
(7.1 matrixed to 5.1). Using this option does <b class="b">NOT</b> mean the encoder will actually
|
|
apply Dolby Surround EX processing.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">notindicated</samp></dt>
|
|
<dd><p>Not Indicated (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Dolby Surround EX Off
|
|
</p></dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>Dolby Surround EX On
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-dheadphone_mode <var class="var">mode</var></samp></dt>
|
|
<dd><p>Dolby Headphone Mode. Indicates whether the stream uses Dolby Headphone
|
|
encoding (multi-channel matrixed to 2.0 for use with headphones). Using this
|
|
option does <b class="b">NOT</b> mean the encoder will actually apply Dolby Headphone
|
|
processing.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">notindicated</samp></dt>
|
|
<dd><p>Not Indicated (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Dolby Headphone Off
|
|
</p></dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>Dolby Headphone On
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-ad_conv_type <var class="var">type</var></samp></dt>
|
|
<dd><p>A/D Converter Type. Indicates whether the audio has passed through HDCD A/D
|
|
conversion.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">standard</samp></dt>
|
|
<dd><p>Standard A/D Converter (default)
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">hdcd</samp></dt>
|
|
<dd><p>HDCD A/D Converter
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="subsection-level-extent" id="Other-AC_002d3-Encoding-Options">
|
|
<h4 class="subsection">8.2.3 Other AC-3 Encoding Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-stereo_rematrixing <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Stereo Rematrixing. Enables/Disables use of rematrixing for stereo input. This
|
|
is an optional AC-3 feature that increases quality by selectively encoding
|
|
the left/right channels as mid/side. This option is enabled by default, and it
|
|
is highly recommended that it be left as enabled except for testing purposes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff <var class="var">frequency</var></samp></dt>
|
|
<dd><p>Set lowpass cutoff frequency. If unspecified, the encoder selects a default
|
|
determined by various other encoding parameters.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options">
|
|
<h4 class="subsection">8.2.4 Floating-Point-Only AC-3 Encoding Options</h4>
|
|
|
|
<p>These options are only valid for the floating-point encoder and do not exist
|
|
for the fixed-point encoder due to the corresponding features not being
|
|
implemented in fixed-point.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">-channel_coupling <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enables/Disables use of channel coupling, which is an optional AC-3 feature
|
|
that increases quality by combining high frequency information from multiple
|
|
channels into a single channel. The per-channel high frequency information is
|
|
sent with less accuracy in both the frequency and time domains. This allows
|
|
more bits to be used for lower frequencies while preserving enough information
|
|
to reconstruct the high frequencies. This option is enabled by default for the
|
|
floating-point encoder and should generally be left as enabled except for
|
|
testing purposes or to increase encoding speed.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">-1</samp></dt>
|
|
<dt><samp class="option">auto</samp></dt>
|
|
<dd><p>Selected by Encoder (default)
|
|
</p></dd>
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">off</samp></dt>
|
|
<dd><p>Disable Channel Coupling
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">on</samp></dt>
|
|
<dd><p>Enable Channel Coupling
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">-cpl_start_band <var class="var">number</var></samp></dt>
|
|
<dd><p>Coupling Start Band. Sets the channel coupling start band, from 1 to 15. If a
|
|
value higher than the bandwidth is used, it will be reduced to 1 less than the
|
|
coupling end band. If <var class="var">auto</var> is used, the start band will be determined by
|
|
the encoder based on the bit rate, sample rate, and channel layout. This option
|
|
has no effect if channel coupling is disabled.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">-1</samp></dt>
|
|
<dt><samp class="option">auto</samp></dt>
|
|
<dd><p>Selected by Encoder (default)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="flac"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="flac-2">
|
|
<h3 class="section">8.3 flac</h3>
|
|
|
|
<p>FLAC (Free Lossless Audio Codec) Encoder
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-10" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-10">
|
|
<h4 class="subsection">8.3.1 Options</h4>
|
|
|
|
<p>The following options are supported by FFmpeg’s flac encoder.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">compression_level</samp></dt>
|
|
<dd><p>Sets the compression level, which chooses defaults for many other options
|
|
if they are not set explicitly. Valid values are from 0 to 12, 5 is the
|
|
default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame_size</samp></dt>
|
|
<dd><p>Sets the size of the frames in samples per channel.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">lpc_coeff_precision</samp></dt>
|
|
<dd><p>Sets the LPC coefficient precision, valid values are from 1 to 15, 15 is the
|
|
default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">lpc_type</samp></dt>
|
|
<dd><p>Sets the first stage LPC algorithm
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">none</samp>’</dt>
|
|
<dd><p>LPC is not used
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">fixed</samp>’</dt>
|
|
<dd><p>fixed LPC coefficients
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">levinson</samp>’</dt>
|
|
<dt>‘<samp class="samp">cholesky</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">lpc_passes</samp></dt>
|
|
<dd><p>Number of passes to use for Cholesky factorization during LPC analysis
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">min_partition_order</samp></dt>
|
|
<dd><p>The minimum partition order
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_partition_order</samp></dt>
|
|
<dd><p>The maximum partition order
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">prediction_order_method</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">estimation</samp>’</dt>
|
|
<dt>‘<samp class="samp">2level</samp>’</dt>
|
|
<dt>‘<samp class="samp">4level</samp>’</dt>
|
|
<dt>‘<samp class="samp">8level</samp>’</dt>
|
|
<dt>‘<samp class="samp">search</samp>’</dt>
|
|
<dd><p>Bruteforce search
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">log</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">ch_mode</samp></dt>
|
|
<dd><p>Channel mode
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dd><p>The mode is chosen automatically for each frame
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">indep</samp>’</dt>
|
|
<dd><p>Channels are independently coded
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">left_side</samp>’</dt>
|
|
<dt>‘<samp class="samp">right_side</samp>’</dt>
|
|
<dt>‘<samp class="samp">mid_side</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">exact_rice_parameters</samp></dt>
|
|
<dd><p>Chooses if rice parameters are calculated exactly or approximately.
|
|
if set to 1 then they are chosen exactly, which slows the code down slightly and
|
|
improves compression slightly.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">multi_dim_quant</samp></dt>
|
|
<dd><p>Multi Dimensional Quantization. If set to 1 then a 2nd stage LPC algorithm is
|
|
applied after the first stage to finetune the coefficients. This is quite slow
|
|
and slightly improves compression.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="opusenc"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="opus">
|
|
<h3 class="section">8.4 opus</h3>
|
|
|
|
<p>Opus encoder.
|
|
</p>
|
|
<p>This is a native FFmpeg encoder for the Opus format. Currently its in development and
|
|
only implements the CELT part of the codec. Its quality is usually worse and at best
|
|
is equal to the libopus encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-11" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-11">
|
|
<h4 class="subsection">8.4.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bit rate in bits/s. If unspecified it uses the number of channels and the layout
|
|
to make a good guess.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">opus_delay</samp></dt>
|
|
<dd><p>Sets the maximum delay in milliseconds. Lower delays than 20ms will very quickly
|
|
decrease quality.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="libfdk_002daac_002denc"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="libfdk_005faac">
|
|
<h3 class="section">8.5 libfdk_aac</h3>
|
|
|
|
<p>libfdk-aac AAC (Advanced Audio Coding) encoder wrapper.
|
|
</p>
|
|
<p>The libfdk-aac library is based on the Fraunhofer FDK AAC code from
|
|
the Android project.
|
|
</p>
|
|
<p>Requires the presence of the libfdk-aac headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libfdk-aac</code>. The library is also incompatible with GPL,
|
|
so if you allow the use of GPL, you should configure with
|
|
<code class="code">--enable-gpl --enable-nonfree --enable-libfdk-aac</code>.
|
|
</p>
|
|
<p>This encoder has support for the AAC-HE profiles.
|
|
</p>
|
|
<p>VBR encoding, enabled through the <samp class="option">vbr</samp> or <samp class="option">flags
|
|
+qscale</samp> options, is experimental and only works with some
|
|
combinations of parameters.
|
|
</p>
|
|
<p>Support for encoding 7.1 audio is only available with libfdk-aac 0.1.3 or
|
|
higher.
|
|
</p>
|
|
<p>For more information see the fdk-aac project at
|
|
<a class="url" href="http://sourceforge.net/p/opencore-amr/fdk-aac/">http://sourceforge.net/p/opencore-amr/fdk-aac/</a>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-12" accesskey="1">Options</a></li>
|
|
<li><a href="#Examples" accesskey="2">Examples</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-12">
|
|
<h4 class="subsection">8.5.1 Options</h4>
|
|
|
|
<p>The following options are mapped on the shared FFmpeg codec options.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bit rate in bits/s. If the bitrate is not explicitly specified, it
|
|
is automatically set to a suitable value depending on the selected
|
|
profile.
|
|
</p>
|
|
<p>In case VBR mode is enabled the option is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ar</samp></dt>
|
|
<dd><p>Set audio sampling rate (in Hz).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">channels</samp></dt>
|
|
<dd><p>Set the number of audio channels.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">flags +qscale</samp></dt>
|
|
<dd><p>Enable fixed quality, VBR (Variable Bit Rate) mode.
|
|
Note that VBR is implicitly enabled when the <samp class="option">vbr</samp> value is
|
|
positive.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff</samp></dt>
|
|
<dd><p>Set cutoff frequency. If not specified (or explicitly set to 0) it
|
|
will use a value automatically computed by the library. Default value
|
|
is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Set audio profile.
|
|
</p>
|
|
<p>The following profiles are recognized:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">aac_low</samp>’</dt>
|
|
<dd><p>Low Complexity AAC (LC)
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_he</samp>’</dt>
|
|
<dd><p>High Efficiency AAC (HE-AAC)
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_he_v2</samp>’</dt>
|
|
<dd><p>High Efficiency AAC version 2 (HE-AACv2)
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_ld</samp>’</dt>
|
|
<dd><p>Low Delay AAC (LD)
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aac_eld</samp>’</dt>
|
|
<dd><p>Enhanced Low Delay AAC (ELD)
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>If not specified it is set to ‘<samp class="samp">aac_low</samp>’.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>The following are private options of the libfdk_aac encoder.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">afterburner</samp></dt>
|
|
<dd><p>Enable afterburner feature if set to 1, disabled if set to 0. This
|
|
improves the quality but also the required processing power.
|
|
</p>
|
|
<p>Default value is 1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">eld_sbr</samp></dt>
|
|
<dd><p>Enable SBR (Spectral Band Replication) for ELD if set to 1, disabled
|
|
if set to 0.
|
|
</p>
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">eld_v2</samp></dt>
|
|
<dd><p>Enable ELDv2 (LD-MPS extension for ELD stereo signals) for ELDv2 if set to 1,
|
|
disabled if set to 0.
|
|
</p>
|
|
<p>Note that option is available when fdk-aac version (AACENCODER_LIB_VL0.AACENCODER_LIB_VL1.AACENCODER_LIB_VL2) > (4.0.0).
|
|
</p>
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">signaling</samp></dt>
|
|
<dd><p>Set SBR/PS signaling style.
|
|
</p>
|
|
<p>It can assume one of the following values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">default</samp>’</dt>
|
|
<dd><p>choose signaling implicitly (explicit hierarchical by default,
|
|
implicit if global header is disabled)
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">implicit</samp>’</dt>
|
|
<dd><p>implicit backwards compatible signaling
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">explicit_sbr</samp>’</dt>
|
|
<dd><p>explicit SBR, implicit PS signaling
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">explicit_hierarchical</samp>’</dt>
|
|
<dd><p>explicit hierarchical signaling
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>Default value is ‘<samp class="samp">default</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">latm</samp></dt>
|
|
<dd><p>Output LATM/LOAS encapsulated data if set to 1, disabled if set to 0.
|
|
</p>
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">header_period</samp></dt>
|
|
<dd><p>Set StreamMuxConfig and PCE repetition period (in frames) for sending
|
|
in-band configuration buffers within LATM/LOAS transport layer.
|
|
</p>
|
|
<p>Must be a 16-bits non-negative integer.
|
|
</p>
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">vbr</samp></dt>
|
|
<dd><p>Set VBR mode, from 1 to 5. 1 is lowest quality (though still pretty
|
|
good) and 5 is highest quality. A value of 0 will disable VBR, and CBR
|
|
(Constant Bit Rate) is enabled.
|
|
</p>
|
|
<p>Currently only the ‘<samp class="samp">aac_low</samp>’ profile supports VBR encoding.
|
|
</p>
|
|
<p>VBR modes 1-5 correspond to roughly the following average bit rates:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">1</samp>’</dt>
|
|
<dd><p>32 kbps/channel
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">2</samp>’</dt>
|
|
<dd><p>40 kbps/channel
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">3</samp>’</dt>
|
|
<dd><p>48-56 kbps/channel
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">4</samp>’</dt>
|
|
<dd><p>64 kbps/channel
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">5</samp>’</dt>
|
|
<dd><p>about 80-96 kbps/channel
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>Default value is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame_length</samp></dt>
|
|
<dd><p>Set the audio frame length in samples. Default value is the internal
|
|
default of the library. Refer to the library’s documentation for information
|
|
about supported values.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Examples">
|
|
<h4 class="subsection">8.5.2 Examples</h4>
|
|
|
|
<ul class="itemize mark-bullet">
|
|
<li>Use <code class="command">ffmpeg</code> to convert an audio file to VBR AAC in an M4A (MP4)
|
|
container:
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input.wav -codec:a libfdk_aac -vbr 3 output.m4a
|
|
</pre></div>
|
|
|
|
</li><li>Use <code class="command">ffmpeg</code> to convert an audio file to CBR 64k kbps AAC, using the
|
|
High-Efficiency AAC profile:
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input.wav -c:a libfdk_aac -profile:a aac_he -b:a 64k output.m4a
|
|
</pre></div>
|
|
</li></ul>
|
|
|
|
<a class="anchor" id="libmp3lame"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="libmp3lame-1">
|
|
<h3 class="section">8.6 libmp3lame</h3>
|
|
|
|
<p>LAME (Lame Ain’t an MP3 Encoder) MP3 encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libmp3lame headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libmp3lame</code>.
|
|
</p>
|
|
<p>See <a class="ref" href="#libshine">libshine</a> for a fixed-point MP3 encoder, although with a
|
|
lower quality.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-13" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-13">
|
|
<h4 class="subsection">8.6.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libmp3lame wrapper. The
|
|
<code class="command">lame</code>-equivalent of the options are listed in parentheses.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt>
|
|
<dd><p>Set bitrate expressed in bits/s for CBR or ABR. LAME <code class="code">bitrate</code> is
|
|
expressed in kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q (<em class="emph">-V</em>)</samp></dt>
|
|
<dd><p>Set constant quality setting for VBR. This option is valid only
|
|
using the <code class="command">ffmpeg</code> command-line tool. For library interface
|
|
users, use <samp class="option">global_quality</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">compression_level (<em class="emph">-q</em>)</samp></dt>
|
|
<dd><p>Set algorithm quality. Valid arguments are integers in the 0-9 range,
|
|
with 0 meaning highest quality but slowest, and 9 meaning fastest
|
|
while producing the worst quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff (<em class="emph">--lowpass</em>)</samp></dt>
|
|
<dd><p>Set lowpass cutoff frequency. If unspecified, the encoder dynamically
|
|
adjusts the cutoff.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">reservoir</samp></dt>
|
|
<dd><p>Enable use of bit reservoir when set to 1. Default value is 1. LAME
|
|
has this enabled by default, but can be overridden by use
|
|
<samp class="option">--nores</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">joint_stereo (<em class="emph">-m j</em>)</samp></dt>
|
|
<dd><p>Enable the encoder to use (on a frame by frame basis) either L/R
|
|
stereo or mid/side stereo. Default value is 1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">abr (<em class="emph">--abr</em>)</samp></dt>
|
|
<dd><p>Enable the encoder to use ABR when set to 1. The <code class="command">lame</code>
|
|
<samp class="option">--abr</samp> sets the target bitrate, while this options only
|
|
tells FFmpeg to use ABR still relies on <samp class="option">b</samp> to set bitrate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">copyright (<em class="emph">-c</em>)</samp></dt>
|
|
<dd><p>Set MPEG audio copyright flag when set to 1. The default value is 0
|
|
(disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">original (<em class="emph">-o</em>)</samp></dt>
|
|
<dd><p>Set MPEG audio original flag when set to 1. The default value is 1
|
|
(enabled).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libopencore_002damrnb-1">
|
|
<h3 class="section">8.7 libopencore-amrnb</h3>
|
|
|
|
<p>OpenCORE Adaptive Multi-Rate Narrowband encoder.
|
|
</p>
|
|
<p>Requires the presence of the libopencore-amrnb headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libopencore-amrnb --enable-version3</code>.
|
|
</p>
|
|
<p>This is a mono-only encoder. Officially it only supports 8000Hz sample rate,
|
|
but you can override it by setting <samp class="option">strict</samp> to ‘<samp class="samp">unofficial</samp>’ or
|
|
lower.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-14" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-14">
|
|
<h4 class="subsection">8.7.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bitrate in bits per second. Only the following bitrates are supported,
|
|
otherwise libavcodec will round to the nearest valid bitrate.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">4750</samp></dt>
|
|
<dt><samp class="option">5150</samp></dt>
|
|
<dt><samp class="option">5900</samp></dt>
|
|
<dt><samp class="option">6700</samp></dt>
|
|
<dt><samp class="option">7400</samp></dt>
|
|
<dt><samp class="option">7950</samp></dt>
|
|
<dt><samp class="option">10200</samp></dt>
|
|
<dt><samp class="option">12200</samp></dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">dtx</samp></dt>
|
|
<dd><p>Allow discontinuous transmission (generate comfort noise) when set to 1. The
|
|
default value is 0 (disabled).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libopus-1">
|
|
<h3 class="section">8.8 libopus</h3>
|
|
|
|
<p>libopus Opus Interactive Audio Codec encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libopus headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libopus</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Option-Mapping" accesskey="1">Option Mapping</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Option-Mapping">
|
|
<h4 class="subsection">8.8.1 Option Mapping</h4>
|
|
|
|
<p>Most libopus options are modelled after the <code class="command">opusenc</code> utility from
|
|
opus-tools. The following is an option mapping chart describing options
|
|
supported by the libopus wrapper, and their <code class="command">opusenc</code>-equivalent
|
|
in parentheses.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">bitrate</em>)</samp></dt>
|
|
<dd><p>Set the bit rate in bits/s. FFmpeg’s <samp class="option">b</samp> option is
|
|
expressed in bits/s, while <code class="command">opusenc</code>’s <samp class="option">bitrate</samp> in
|
|
kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">vbr (<em class="emph">vbr</em>, <em class="emph">hard-cbr</em>, and <em class="emph">cvbr</em>)</samp></dt>
|
|
<dd><p>Set VBR mode. The FFmpeg <samp class="option">vbr</samp> option has the following
|
|
valid arguments, with the <code class="command">opusenc</code> equivalent options
|
|
in parentheses:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">off (<em class="emph">hard-cbr</em>)</samp>’</dt>
|
|
<dd><p>Use constant bit rate encoding.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">on (<em class="emph">vbr</em>)</samp>’</dt>
|
|
<dd><p>Use variable bit rate encoding (the default).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">constrained (<em class="emph">cvbr</em>)</samp>’</dt>
|
|
<dd><p>Use constrained variable bit rate encoding.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">compression_level (<em class="emph">comp</em>)</samp></dt>
|
|
<dd><p>Set encoding algorithm complexity. Valid options are integers in
|
|
the 0-10 range. 0 gives the fastest encodes but lower quality, while 10
|
|
gives the highest quality but slowest encoding. The default is 10.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame_duration (<em class="emph">framesize</em>)</samp></dt>
|
|
<dd><p>Set maximum frame size, or duration of a frame in milliseconds. The
|
|
argument must be exactly the following: 2.5, 5, 10, 20, 40, 60. Smaller
|
|
frame sizes achieve lower latency but less quality at a given bitrate.
|
|
Sizes greater than 20ms are only interesting at fairly low bitrates.
|
|
The default is 20ms.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">packet_loss (<em class="emph">expect-loss</em>)</samp></dt>
|
|
<dd><p>Set expected packet loss percentage. The default is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">fec (<em class="emph">n/a</em>)</samp></dt>
|
|
<dd><p>Enable inband forward error correction. <samp class="option">packet_loss</samp> must be non-zero
|
|
to take advantage - frequency of FEC ’side-data’ is proportional to expected packet loss.
|
|
Default is disabled.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">application (N.A.)</samp></dt>
|
|
<dd><p>Set intended application type. Valid options are listed below:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">voip</samp>’</dt>
|
|
<dd><p>Favor improved speech intelligibility.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">audio</samp>’</dt>
|
|
<dd><p>Favor faithfulness to the input (the default).
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">lowdelay</samp>’</dt>
|
|
<dd><p>Restrict to only the lowest delay modes.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">cutoff (N.A.)</samp></dt>
|
|
<dd><p>Set cutoff bandwidth in Hz. The argument must be exactly one of the
|
|
following: 4000, 6000, 8000, 12000, or 20000, corresponding to
|
|
narrowband, mediumband, wideband, super wideband, and fullband
|
|
respectively. The default is 0 (cutoff disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mapping_family (<em class="emph">mapping_family</em>)</samp></dt>
|
|
<dd><p>Set channel mapping family to be used by the encoder. The default value of -1
|
|
uses mapping family 0 for mono and stereo inputs, and mapping family 1
|
|
otherwise. The default also disables the surround masking and LFE bandwidth
|
|
optimzations in libopus, and requires that the input contains 8 channels or
|
|
fewer.
|
|
</p>
|
|
<p>Other values include 0 for mono and stereo, 1 for surround sound with masking
|
|
and LFE bandwidth optimizations, and 255 for independent streams with an
|
|
unspecified channel layout.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">apply_phase_inv (N.A.) (requires libopus >= 1.2)</samp></dt>
|
|
<dd><p>If set to 0, disables the use of phase inversion for intensity stereo,
|
|
improving the quality of mono downmixes, but slightly reducing normal stereo
|
|
quality. The default is 1 (phase inversion enabled).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="libshine"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="libshine-1">
|
|
<h3 class="section">8.9 libshine</h3>
|
|
|
|
<p>Shine Fixed-Point MP3 encoder wrapper.
|
|
</p>
|
|
<p>Shine is a fixed-point MP3 encoder. It has a far better performance on
|
|
platforms without an FPU, e.g. armel CPUs, and some phones and tablets.
|
|
However, as it is more targeted on performance than quality, it is not on par
|
|
with LAME and other production-grade encoders quality-wise. Also, according to
|
|
the project’s homepage, this encoder may not be free of bugs as the code was
|
|
written a long time ago and the project was dead for at least 5 years.
|
|
</p>
|
|
<p>This encoder only supports stereo and mono input. This is also CBR-only.
|
|
</p>
|
|
<p>The original project (last updated in early 2007) is at
|
|
<a class="url" href="http://sourceforge.net/projects/libshine-fxp/">http://sourceforge.net/projects/libshine-fxp/</a>. We only support the
|
|
updated fork by the Savonet/Liquidsoap project at <a class="url" href="https://github.com/savonet/shine">https://github.com/savonet/shine</a>.
|
|
</p>
|
|
<p>Requires the presence of the libshine headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libshine</code>.
|
|
</p>
|
|
<p>See also <a class="ref" href="#libmp3lame">libmp3lame</a>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-15" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-15">
|
|
<h4 class="subsection">8.9.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libshine wrapper. The
|
|
<code class="command">shineenc</code>-equivalent of the options are listed in parentheses.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt>
|
|
<dd><p>Set bitrate expressed in bits/s for CBR. <code class="command">shineenc</code> <samp class="option">-b</samp> option
|
|
is expressed in kilobits/s.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libtwolame">
|
|
<h3 class="section">8.10 libtwolame</h3>
|
|
|
|
<p>TwoLAME MP2 encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libtwolame headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libtwolame</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-16" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-16">
|
|
<h4 class="subsection">8.10.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libtwolame wrapper. The
|
|
<code class="command">twolame</code>-equivalent options follow the FFmpeg ones and are in
|
|
parentheses.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt>
|
|
<dd><p>Set bitrate expressed in bits/s for CBR. <code class="command">twolame</code> <samp class="option">b</samp>
|
|
option is expressed in kilobits/s. Default value is 128k.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q (<em class="emph">-V</em>)</samp></dt>
|
|
<dd><p>Set quality for experimental VBR support. Maximum value range is
|
|
from -50 to 50, useful range is from -10 to 10. The higher the
|
|
value, the better the quality. This option is valid only using the
|
|
<code class="command">ffmpeg</code> command-line tool. For library interface users,
|
|
use <samp class="option">global_quality</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mode (<em class="emph">--mode</em>)</samp></dt>
|
|
<dd><p>Set the mode of the resulting audio. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dd><p>Choose mode automatically based on the input. This is the default.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">stereo</samp>’</dt>
|
|
<dd><p>Stereo
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">joint_stereo</samp>’</dt>
|
|
<dd><p>Joint stereo
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">dual_channel</samp>’</dt>
|
|
<dd><p>Dual channel
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">mono</samp>’</dt>
|
|
<dd><p>Mono
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">psymodel (<em class="emph">--psyc-mode</em>)</samp></dt>
|
|
<dd><p>Set psychoacoustic model to use in encoding. The argument must be
|
|
an integer between -1 and 4, inclusive. The higher the value, the
|
|
better the quality. The default value is 3.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">energy_levels (<em class="emph">--energy</em>)</samp></dt>
|
|
<dd><p>Enable energy levels extensions when set to 1. The default value is
|
|
0 (disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">error_protection (<em class="emph">--protect</em>)</samp></dt>
|
|
<dd><p>Enable CRC error protection when set to 1. The default value is 0
|
|
(disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">copyright (<em class="emph">--copyright</em>)</samp></dt>
|
|
<dd><p>Set MPEG audio copyright flag when set to 1. The default value is 0
|
|
(disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">original (<em class="emph">--original</em>)</samp></dt>
|
|
<dd><p>Set MPEG audio original flag when set to 1. The default value is 0
|
|
(disabled).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libvo_002damrwbenc">
|
|
<h3 class="section">8.11 libvo-amrwbenc</h3>
|
|
|
|
<p>VisualOn Adaptive Multi-Rate Wideband encoder.
|
|
</p>
|
|
<p>Requires the presence of the libvo-amrwbenc headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libvo-amrwbenc --enable-version3</code>.
|
|
</p>
|
|
<p>This is a mono-only encoder. Officially it only supports 16000Hz sample
|
|
rate, but you can override it by setting <samp class="option">strict</samp> to
|
|
‘<samp class="samp">unofficial</samp>’ or lower.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-17" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-17">
|
|
<h4 class="subsection">8.11.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bitrate in bits/s. Only the following bitrates are supported, otherwise
|
|
libavcodec will round to the nearest valid bitrate.
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">6600</samp>’</dt>
|
|
<dt>‘<samp class="samp">8850</samp>’</dt>
|
|
<dt>‘<samp class="samp">12650</samp>’</dt>
|
|
<dt>‘<samp class="samp">14250</samp>’</dt>
|
|
<dt>‘<samp class="samp">15850</samp>’</dt>
|
|
<dt>‘<samp class="samp">18250</samp>’</dt>
|
|
<dt>‘<samp class="samp">19850</samp>’</dt>
|
|
<dt>‘<samp class="samp">23050</samp>’</dt>
|
|
<dt>‘<samp class="samp">23850</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">dtx</samp></dt>
|
|
<dd><p>Allow discontinuous transmission (generate comfort noise) when set to 1. The
|
|
default value is 0 (disabled).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libvorbis">
|
|
<h3 class="section">8.12 libvorbis</h3>
|
|
|
|
<p>libvorbis encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libvorbisenc headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libvorbis</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-18" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-18">
|
|
<h4 class="subsection">8.12.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libvorbis wrapper. The
|
|
<code class="command">oggenc</code>-equivalent of the options are listed in parentheses.
|
|
</p>
|
|
<p>To get a more accurate and extensive documentation of the libvorbis
|
|
options, consult the libvorbisenc’s and <code class="command">oggenc</code>’s documentations.
|
|
See <a class="url" href="http://xiph.org/vorbis/">http://xiph.org/vorbis/</a>,
|
|
<a class="url" href="http://wiki.xiph.org/Vorbis-tools">http://wiki.xiph.org/Vorbis-tools</a>, and oggenc(1).
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt>
|
|
<dd><p>Set bitrate expressed in bits/s for ABR. <code class="command">oggenc</code> <samp class="option">-b</samp> is
|
|
expressed in kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q (<em class="emph">-q</em>)</samp></dt>
|
|
<dd><p>Set constant quality setting for VBR. The value should be a float
|
|
number in the range of -1.0 to 10.0. The higher the value, the better
|
|
the quality. The default value is ‘<samp class="samp">3.0</samp>’.
|
|
</p>
|
|
<p>This option is valid only using the <code class="command">ffmpeg</code> command-line tool.
|
|
For library interface users, use <samp class="option">global_quality</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cutoff (<em class="emph">--advanced-encode-option lowpass_frequency=N</em>)</samp></dt>
|
|
<dd><p>Set cutoff bandwidth in Hz, a value of 0 disables cutoff. <code class="command">oggenc</code>’s
|
|
related option is expressed in kHz. The default value is ‘<samp class="samp">0</samp>’ (cutoff
|
|
disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minrate (<em class="emph">-m</em>)</samp></dt>
|
|
<dd><p>Set minimum bitrate expressed in bits/s. <code class="command">oggenc</code> <samp class="option">-m</samp> is
|
|
expressed in kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">maxrate (<em class="emph">-M</em>)</samp></dt>
|
|
<dd><p>Set maximum bitrate expressed in bits/s. <code class="command">oggenc</code> <samp class="option">-M</samp> is
|
|
expressed in kilobits/s. This only has effect on ABR mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">iblock (<em class="emph">--advanced-encode-option impulse_noisetune=N</em>)</samp></dt>
|
|
<dd><p>Set noise floor bias for impulse blocks. The value is a float number from
|
|
-15.0 to 0.0. A negative bias instructs the encoder to pay special attention
|
|
to the crispness of transients in the encoded audio. The tradeoff for better
|
|
transient response is a higher bitrate.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="mjpegenc"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="mjpeg">
|
|
<h3 class="section">8.13 mjpeg</h3>
|
|
|
|
<p>Motion JPEG encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-19" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-19">
|
|
<h4 class="subsection">8.13.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">huffman</samp></dt>
|
|
<dd><p>Set the huffman encoding strategy. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">default</samp>’</dt>
|
|
<dd><p>Use the default huffman tables. This is the default strategy.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">optimal</samp>’</dt>
|
|
<dd><p>Compute and use optimal huffman tables.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
<a class="anchor" id="wavpackenc"></a></div>
|
|
</div>
|
|
<div class="section-level-extent" id="wavpack">
|
|
<h3 class="section">8.14 wavpack</h3>
|
|
|
|
<p>WavPack lossless audio encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-20" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-20">
|
|
<h4 class="subsection">8.14.1 Options</h4>
|
|
|
|
<p>The equivalent options for <code class="command">wavpack</code> command line utility are listed in
|
|
parentheses.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Shared-options" accesskey="1">Shared options</a></li>
|
|
<li><a href="#Private-options" accesskey="2">Private options</a></li>
|
|
</ul>
|
|
<div class="subsubsection-level-extent" id="Shared-options">
|
|
<h4 class="subsubsection">8.14.1.1 Shared options</h4>
|
|
|
|
<p>The following shared options are effective for this encoder. Only special notes
|
|
about this particular encoder will be documented here. For the general meaning
|
|
of the options, see <a class="ref" href="#codec_002doptions">the Codec Options chapter</a>.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">frame_size (<em class="emph">--blocksize</em>)</samp></dt>
|
|
<dd><p>For this encoder, the range for this option is between 128 and 131072. Default
|
|
is automatically decided based on sample rate and number of channel.
|
|
</p>
|
|
<p>For the complete formula of calculating default, see
|
|
<samp class="file">libavcodec/wavpackenc.c</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">compression_level (<em class="emph">-f</em>, <em class="emph">-h</em>, <em class="emph">-hh</em>, and <em class="emph">-x</em>)</samp></dt>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsubsection-level-extent" id="Private-options">
|
|
<h4 class="subsubsection">8.14.1.2 Private options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">joint_stereo (<em class="emph">-j</em>)</samp></dt>
|
|
<dd><p>Set whether to enable joint stereo. Valid values are:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">on (<em class="emph">1</em>)</samp>’</dt>
|
|
<dd><p>Force mid/side audio encoding.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">off (<em class="emph">0</em>)</samp>’</dt>
|
|
<dd><p>Force left/right audio encoding.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dd><p>Let the encoder decide automatically.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">optimize_mono</samp></dt>
|
|
<dd><p>Set whether to enable optimization for mono. This option is only effective for
|
|
non-mono streams. Available values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">on</samp>’</dt>
|
|
<dd><p>enabled
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">off</samp>’</dt>
|
|
<dd><p>disabled
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Video-Encoders">
|
|
<h2 class="chapter">9 Video Encoders</h2>
|
|
|
|
<p>A description of some of the currently available video encoders
|
|
follows.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#a64_005fmulti_002c-a64_005fmulti5" accesskey="1">a64_multi, a64_multi5</a></li>
|
|
<li><a href="#Cinepak" accesskey="2">Cinepak</a></li>
|
|
<li><a href="#GIF" accesskey="3">GIF</a></li>
|
|
<li><a href="#Hap" accesskey="4">Hap</a></li>
|
|
<li><a href="#jpeg2000" accesskey="5">jpeg2000</a></li>
|
|
<li><a href="#librav1e" accesskey="6">librav1e</a></li>
|
|
<li><a href="#libaom_002dav1" accesskey="7">libaom-av1</a></li>
|
|
<li><a href="#libsvtav1" accesskey="8">libsvtav1</a></li>
|
|
<li><a href="#libjxl" accesskey="9">libjxl</a></li>
|
|
<li><a href="#libkvazaar">libkvazaar</a></li>
|
|
<li><a href="#libopenh264">libopenh264</a></li>
|
|
<li><a href="#libtheora">libtheora</a></li>
|
|
<li><a href="#libvpx">libvpx</a></li>
|
|
<li><a href="#libwebp">libwebp</a></li>
|
|
<li><a href="#libx264_002c-libx264rgb">libx264, libx264rgb</a></li>
|
|
<li><a href="#libx265">libx265</a></li>
|
|
<li><a href="#libxavs2">libxavs2</a></li>
|
|
<li><a href="#libxvid">libxvid</a></li>
|
|
<li><a href="#MediaFoundation">MediaFoundation</a></li>
|
|
<li><a href="#mpeg2">mpeg2</a></li>
|
|
<li><a href="#png">png</a></li>
|
|
<li><a href="#ProRes">ProRes</a></li>
|
|
<li><a href="#QSV-Encoders">QSV Encoders</a></li>
|
|
<li><a href="#snow">snow</a></li>
|
|
<li><a href="#VAAPI-encoders">VAAPI encoders</a></li>
|
|
<li><a href="#vbn">vbn</a></li>
|
|
<li><a href="#vc2">vc2</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="a64_005fmulti_002c-a64_005fmulti5">
|
|
<h3 class="section">9.1 a64_multi, a64_multi5</h3>
|
|
|
|
<p>A64 / Commodore 64 multicolor charset encoder. <code class="code">a64_multi5</code> is extended with 5th color (colram).
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="Cinepak">
|
|
<h3 class="section">9.2 Cinepak</h3>
|
|
|
|
<p>Cinepak aka CVID encoder.
|
|
Compatible with Windows 3.1 and vintage MacOS.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-21" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-21">
|
|
<h4 class="subsection">9.2.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">g <var class="var">integer</var></samp></dt>
|
|
<dd><p>Keyframe interval.
|
|
A keyframe is inserted at least every <code class="code">-g</code> frames, sometimes sooner.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q:v <var class="var">integer</var></samp></dt>
|
|
<dd><p>Quality factor. Lower is better. Higher gives lower bitrate.
|
|
The following table lists bitrates when encoding akiyo_cif.y4m for various values of <code class="code">-q:v</code> with <code class="code">-g 100</code>:
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><code class="code">-q:v 1</code> 1918 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 2</code> 1735 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 4</code> 1500 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 10</code> 1041 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 20</code> 826 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 40</code> 553 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 100</code> 394 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 200</code> 312 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 400</code> 266 kb/s</samp></dt>
|
|
<dt><samp class="option"><code class="code">-q:v 1000</code> 237 kb/s</samp></dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">max_extra_cb_iterations <var class="var">integer</var></samp></dt>
|
|
<dd><p>Max extra codebook recalculation passes, more is better and slower.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">skip_empty_cb <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Avoid wasting bytes, ignore vintage MacOS decoder.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_strips <var class="var">integer</var></samp></dt>
|
|
<dt><samp class="option">min_strips <var class="var">integer</var></samp></dt>
|
|
<dd><p>The minimum and maximum number of strips to use.
|
|
Wider range sometimes improves quality.
|
|
More strips is generally better quality but costs more bits.
|
|
Fewer strips tend to yield more keyframes.
|
|
Vintage compatible is 1..3.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">strip_number_adaptivity <var class="var">integer</var></samp></dt>
|
|
<dd><p>How much number of strips is allowed to change between frames.
|
|
Higher is better but slower.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="GIF">
|
|
<h3 class="section">9.3 GIF</h3>
|
|
|
|
<p>GIF image/animation encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-22" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-22">
|
|
<h4 class="subsection">9.3.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">gifflags <var class="var">integer</var></samp></dt>
|
|
<dd><p>Sets the flags used for GIF encoding.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">offsetting</samp></dt>
|
|
<dd><p>Enables picture offsetting.
|
|
</p>
|
|
<p>Default is enabled.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">transdiff</samp></dt>
|
|
<dd><p>Enables transparency detection between frames.
|
|
</p>
|
|
<p>Default is enabled.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">gifimage <var class="var">integer</var></samp></dt>
|
|
<dd><p>Enables encoding one full GIF image per frame, rather than an animated GIF.
|
|
</p>
|
|
<p>Default value is <samp class="option">0</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">global_palette <var class="var">integer</var></samp></dt>
|
|
<dd><p>Writes a palette to the global GIF header where feasible.
|
|
</p>
|
|
<p>If disabled, every frame will always have a palette written, even if there
|
|
is a global palette supplied.
|
|
</p>
|
|
<p>Default value is <samp class="option">1</samp>.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="Hap">
|
|
<h3 class="section">9.4 Hap</h3>
|
|
|
|
<p>Vidvox Hap video encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-23" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-23">
|
|
<h4 class="subsection">9.4.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">format <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specifies the Hap format to encode.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">hap</samp></dt>
|
|
<dt><samp class="option">hap_alpha</samp></dt>
|
|
<dt><samp class="option">hap_q</samp></dt>
|
|
</dl>
|
|
|
|
<p>Default value is <samp class="option">hap</samp>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">chunks <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specifies the number of chunks to split frames into, between 1 and 64. This
|
|
permits multithreaded decoding of large frames, potentially at the cost of
|
|
data-rate. The encoder may modify this value to divide frames evenly.
|
|
</p>
|
|
<p>Default value is <var class="var">1</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">compressor <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specifies the second-stage compressor to use. If set to <samp class="option">none</samp>,
|
|
<samp class="option">chunks</samp> will be limited to 1, as chunked uncompressed frames offer no
|
|
benefit.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">none</samp></dt>
|
|
<dt><samp class="option">snappy</samp></dt>
|
|
</dl>
|
|
|
|
<p>Default value is <samp class="option">snappy</samp>.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="jpeg2000">
|
|
<h3 class="section">9.5 jpeg2000</h3>
|
|
|
|
<p>The native jpeg 2000 encoder is lossy by default, the <code class="code">-q:v</code>
|
|
option can be used to set the encoding quality. Lossless encoding
|
|
can be selected with <code class="code">-pred 1</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-24" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-24">
|
|
<h4 class="subsection">9.5.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">format <var class="var">integer</var></samp></dt>
|
|
<dd><p>Can be set to either <code class="code">j2k</code> or <code class="code">jp2</code> (the default) that
|
|
makes it possible to store non-rgb pix_fmts.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile_width <var class="var">integer</var></samp></dt>
|
|
<dd><p>Sets tile width. Range is 1 to 1073741824. Default is 256.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile_height <var class="var">integer</var></samp></dt>
|
|
<dd><p>Sets tile height. Range is 1 to 1073741824. Default is 256.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">pred <var class="var">integer</var></samp></dt>
|
|
<dd><p>Allows setting the discrete wavelet transform (DWT) type
|
|
</p><dl class="table">
|
|
<dt><samp class="option">dwt97int (Lossy)</samp></dt>
|
|
<dt><samp class="option">dwt53 (Lossless)</samp></dt>
|
|
</dl>
|
|
<p>Default is <code class="code">dwt97int</code>
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sop <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enable this to add SOP marker at the start of each packet. Disabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">eph <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enable this to add EPH marker at the end of each packet header. Disabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">prog <var class="var">integer</var></samp></dt>
|
|
<dd><p>Sets the progression order to be used by the encoder.
|
|
Possible values are:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">lrcp</samp></dt>
|
|
<dt><samp class="option">rlcp</samp></dt>
|
|
<dt><samp class="option">rpcl</samp></dt>
|
|
<dt><samp class="option">pcrl</samp></dt>
|
|
<dt><samp class="option">cprl</samp></dt>
|
|
</dl>
|
|
<p>Set to <code class="code">lrcp</code> by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">layer_rates <var class="var">string</var></samp></dt>
|
|
<dd><p>By default, when this option is not used, compression is done using the quality metric.
|
|
This option allows for compression using compression ratio. The compression ratio for each
|
|
level could be specified. The compression ratio of a layer <code class="code">l</code> species the what ratio of
|
|
total file size is contained in the first <code class="code">l</code> layers.
|
|
</p>
|
|
<p>Example usage:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input.bmp -c:v jpeg2000 -layer_rates "100,10,1" output.j2k
|
|
</pre></div>
|
|
|
|
<p>This would compress the image to contain 3 layers, where the data contained in the
|
|
first layer would be compressed by 1000 times, compressed by 100 in the first two layers,
|
|
and shall contain all data while using all 3 layers.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="librav1e">
|
|
<h3 class="section">9.6 librav1e</h3>
|
|
|
|
<p>rav1e AV1 encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the rav1e headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-librav1e</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-25" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-25">
|
|
<h4 class="subsection">9.6.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">qmax</samp></dt>
|
|
<dd><p>Sets the maximum quantizer to use when using bitrate mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmin</samp></dt>
|
|
<dd><p>Sets the minimum quantizer to use when using bitrate mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qp</samp></dt>
|
|
<dd><p>Uses quantizer mode to encode at the given quantizer (0-255).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">speed</samp></dt>
|
|
<dd><p>Selects the speed preset (0-10) to encode with.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tiles</samp></dt>
|
|
<dd><p>Selects how many tiles to encode with.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile-rows</samp></dt>
|
|
<dd><p>Selects how many rows of tiles to encode with.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile-columns</samp></dt>
|
|
<dd><p>Selects how many columns of tiles to encode with.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">rav1e-params</samp></dt>
|
|
<dd><p>Set rav1e options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated
|
|
by ":". See <code class="command">rav1e --help</code> for a list of options.
|
|
</p>
|
|
<p>For example to specify librav1e encoding options with <samp class="option">-rav1e-params</samp>:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input -c:v librav1e -b:v 500K -rav1e-params speed=5:low_latency=true output.mp4
|
|
</pre></div>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libaom_002dav1">
|
|
<h3 class="section">9.7 libaom-av1</h3>
|
|
|
|
<p>libaom AV1 encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libaom headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libaom</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-26" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-26">
|
|
<h4 class="subsection">9.7.1 Options</h4>
|
|
|
|
<p>The wrapper supports the following standard libavcodec options:
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set bitrate target in bits/second. By default this will use
|
|
variable-bitrate mode. If <samp class="option">maxrate</samp> and <samp class="option">minrate</samp> are
|
|
also set to the same value then it will use constant-bitrate mode,
|
|
otherwise if <samp class="option">crf</samp> is set as well then it will use
|
|
constrained-quality mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">g keyint_min</samp></dt>
|
|
<dd><p>Set key frame placement. The GOP size sets the maximum distance between
|
|
key frames; if zero the output stream will be intra-only. The minimum
|
|
distance is ignored unless it is the same as the GOP size, in which case
|
|
key frames will always appear at a fixed interval. Not set by default,
|
|
so without this option the library has completely free choice about
|
|
where to place key frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmin qmax</samp></dt>
|
|
<dd><p>Set minimum/maximum quantisation values. Valid range is from 0 to 63
|
|
(warning: this does not match the quantiser values actually used by AV1
|
|
- divide by four to map real quantiser values to this range). Defaults
|
|
to min/max (no constraint).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minrate maxrate bufsize rc_init_occupancy</samp></dt>
|
|
<dd><p>Set rate control buffering parameters. Not used if not set - defaults
|
|
to unconstrained variable bitrate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">threads</samp></dt>
|
|
<dd><p>Set the number of threads to use while encoding. This may require the
|
|
<samp class="option">tiles</samp> or <samp class="option">row-mt</samp> options to also be set to actually
|
|
use the specified number of threads fully. Defaults to the number of
|
|
hardware threads supported by the host machine.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Set the encoding profile. Defaults to using the profile which matches
|
|
the bit depth and chroma subsampling of the input.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>The wrapper also has some specific options:
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">cpu-used</samp></dt>
|
|
<dd><p>Set the quality/encoding speed tradeoff. Valid range is from 0 to 8,
|
|
higher numbers indicating greater speed and lower quality. The default
|
|
value is 1, which will be slow and high quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">auto-alt-ref</samp></dt>
|
|
<dd><p>Enable use of alternate reference frames. Defaults to the internal
|
|
default of the library.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">arnr-max-frames (<em class="emph">frames</em>)</samp></dt>
|
|
<dd><p>Set altref noise reduction max frame count. Default is -1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">arnr-strength (<em class="emph">strength</em>)</samp></dt>
|
|
<dd><p>Set altref noise reduction filter strength. Range is -1 to 6. Default is -1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aq-mode (<em class="emph">aq-mode</em>)</samp></dt>
|
|
<dd><p>Set adaptive quantization mode. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt>
|
|
<dd><p>Disabled.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">variance (<em class="emph">1</em>)</samp>’</dt>
|
|
<dd><p>Variance-based.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">complexity (<em class="emph">2</em>)</samp>’</dt>
|
|
<dd><p>Complexity-based.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">cyclic (<em class="emph">3</em>)</samp>’</dt>
|
|
<dd><p>Cyclic refresh.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt>
|
|
<dd><p>Set the distortion metric the encoder is tuned with. Default is <code class="code">psnr</code>.
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">psnr (<em class="emph">0</em>)</samp>’</dt>
|
|
<dt>‘<samp class="samp">ssim (<em class="emph">1</em>)</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">lag-in-frames</samp></dt>
|
|
<dd><p>Set the maximum number of frames which the encoder may keep in flight
|
|
at any one time for lookahead purposes. Defaults to the internal
|
|
default of the library.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">error-resilience</samp></dt>
|
|
<dd><p>Enable error resilience features:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">default</samp></dt>
|
|
<dd><p>Improve resilience against losses of whole frames.
|
|
</p></dd>
|
|
</dl>
|
|
<p>Not enabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf</samp></dt>
|
|
<dd><p>Set the quality/size tradeoff for constant-quality (no bitrate target)
|
|
and constrained-quality (with maximum bitrate target) modes. Valid
|
|
range is 0 to 63, higher numbers indicating lower quality and smaller
|
|
output size. Only used if set; by default only the bitrate target is
|
|
used.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">static-thresh</samp></dt>
|
|
<dd><p>Set a change threshold on blocks below which they will be skipped by
|
|
the encoder. Defined in arbitrary units as a nonnegative integer,
|
|
defaulting to zero (no blocks are skipped).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">drop-threshold</samp></dt>
|
|
<dd><p>Set a threshold for dropping frames when close to rate control bounds.
|
|
Defined as a percentage of the target buffer - when the rate control
|
|
buffer falls below this percentage, frames will be dropped until it
|
|
has refilled above the threshold. Defaults to zero (no frames are
|
|
dropped).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">denoise-noise-level (<em class="emph">level</em>)</samp></dt>
|
|
<dd><p>Amount of noise to be removed for grain synthesis. Grain synthesis is disabled if
|
|
this option is not set or set to 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">denoise-block-size (<em class="emph">pixels</em>)</samp></dt>
|
|
<dd><p>Block size used for denoising for grain synthesis. If not set, AV1 codec
|
|
uses the default value of 32.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">undershoot-pct (<em class="emph">pct</em>)</samp></dt>
|
|
<dd><p>Set datarate undershoot (min) percentage of the target bitrate. Range is -1 to 100.
|
|
Default is -1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">overshoot-pct (<em class="emph">pct</em>)</samp></dt>
|
|
<dd><p>Set datarate overshoot (max) percentage of the target bitrate. Range is -1 to 1000.
|
|
Default is -1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minsection-pct (<em class="emph">pct</em>)</samp></dt>
|
|
<dd><p>Minimum percentage variation of the GOP bitrate from the target bitrate. If minsection-pct
|
|
is not set, the libaomenc wrapper computes it as follows: <code class="code">(minrate * 100 / bitrate)</code>.
|
|
Range is -1 to 100. Default is -1 (unset).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">maxsection-pct (<em class="emph">pct</em>)</samp></dt>
|
|
<dd><p>Maximum percentage variation of the GOP bitrate from the target bitrate. If maxsection-pct
|
|
is not set, the libaomenc wrapper computes it as follows: <code class="code">(maxrate * 100 / bitrate)</code>.
|
|
Range is -1 to 5000. Default is -1 (unset).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">frame-parallel (<em class="emph">boolean</em>)</samp></dt>
|
|
<dd><p>Enable frame parallel decodability features. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tiles</samp></dt>
|
|
<dd><p>Set the number of tiles to encode the input video with, as columns x
|
|
rows. Larger numbers allow greater parallelism in both encoding and
|
|
decoding, but may decrease coding efficiency. Defaults to the minimum
|
|
number of tiles required by the size of the input video (this is 1x1
|
|
(that is, a single tile) for sizes up to and including 4K).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile-columns tile-rows</samp></dt>
|
|
<dd><p>Set the number of tiles as log2 of the number of tile rows and columns.
|
|
Provided for compatibility with libvpx/VP9.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">row-mt (Requires libaom >= 1.0.0-759-g90a15f4f2)</samp></dt>
|
|
<dd><p>Enable row based multi-threading. Disabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-cdef (<em class="emph">boolean</em>)</samp></dt>
|
|
<dd><p>Enable Constrained Directional Enhancement Filter. The libaom-av1
|
|
encoder enables CDEF by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-restoration (<em class="emph">boolean</em>)</samp></dt>
|
|
<dd><p>Enable Loop Restoration Filter. Default is true for libaom-av1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-global-motion (<em class="emph">boolean</em>)</samp></dt>
|
|
<dd><p>Enable the use of global motion for block prediction. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-intrabc (<em class="emph">boolean</em>)</samp></dt>
|
|
<dd><p>Enable block copy mode for intra block prediction. This mode is
|
|
useful for screen content. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-rect-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable rectangular partitions. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-1to4-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable 1:4/4:1 partitions. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-ab-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable AB shape partitions. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-angle-delta (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable angle delta intra prediction. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-cfl-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable chroma predicted from luma intra prediction. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-filter-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable filter intra predictor. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-intra-edge-filter (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable intra edge filter. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-smooth-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable smooth intra prediction mode. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-paeth-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable paeth predictor in intra prediction. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-palette (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable palette prediction mode. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-flip-idtx (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable extended transform type, including FLIPADST_DCT, DCT_FLIPADST,
|
|
FLIPADST_FLIPADST, ADST_FLIPADST, FLIPADST_ADST, IDTX, V_DCT, H_DCT,
|
|
V_ADST, H_ADST, V_FLIPADST, H_FLIPADST. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-tx64 (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable 64-pt transform. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">reduced-tx-type-set (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Use reduced set of transform types. Default is false.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">use-intra-dct-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Use DCT only for INTRA modes. Default is false.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">use-inter-dct-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Use DCT only for INTER modes. Default is false.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">use-intra-default-tx-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Use Default-transform only for INTRA modes. Default is false.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-ref-frame-mvs (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable temporal mv prediction. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-reduced-reference-set (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Use reduced set of single and compound references. Default is false.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-obmc (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable obmc. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-dual-filter (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable dual filter. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-diff-wtd-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable difference-weighted compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-dist-wtd-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable distance-weighted compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-onesided-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable one sided compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-interinter-wedge (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable interinter wedge compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-interintra-wedge (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable interintra wedge compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-masked-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable masked compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-interintra-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable interintra compound. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">enable-smooth-interintra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt>
|
|
<dd><p>Enable smooth interintra mode. Default is true.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aom-params</samp></dt>
|
|
<dd><p>Set libaom options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated
|
|
by ":". For a list of supported options, see <code class="command">aomenc --help</code> under the
|
|
section "AV1 Specific Options".
|
|
</p>
|
|
<p>For example to specify libaom encoding options with <samp class="option">-aom-params</samp>:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input -c:v libaom-av1 -b:v 500K -aom-params tune=psnr:enable-tpl-model=1 output.mp4
|
|
</pre></div>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libsvtav1">
|
|
<h3 class="section">9.8 libsvtav1</h3>
|
|
|
|
<p>SVT-AV1 encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the SVT-AV1 headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libsvtav1</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-27" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-27">
|
|
<h4 class="subsection">9.8.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Set the encoding profile.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
<dt>‘<samp class="samp">professional</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">level</samp></dt>
|
|
<dd><p>Set the operating point level. For example: ’4.0’
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">hielevel</samp></dt>
|
|
<dd><p>Set the Hierarchical prediction levels.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">3level</samp>’</dt>
|
|
<dt>‘<samp class="samp">4level</samp>’</dt>
|
|
<dd><p>This is the default.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">tier</samp></dt>
|
|
<dd><p>Set the operating point tier.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dd><p>This is the default.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">qmax</samp></dt>
|
|
<dd><p>Set the maximum quantizer to use when using a bitrate mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmin</samp></dt>
|
|
<dd><p>Set the minimum quantizer to use when using a bitrate mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf</samp></dt>
|
|
<dd><p>Constant rate factor value used in crf rate control mode (0-63).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qp</samp></dt>
|
|
<dd><p>Set the quantizer used in cqp rate control mode (0-63).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sc_detection</samp></dt>
|
|
<dd><p>Enable scene change detection.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">la_depth</samp></dt>
|
|
<dd><p>Set number of frames to look ahead (0-120).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">preset</samp></dt>
|
|
<dd><p>Set the quality-speed tradeoff, in the range 0 to 13. Higher values are
|
|
faster but lower quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile_rows</samp></dt>
|
|
<dd><p>Set log2 of the number of rows of tiles to use (0-6).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tile_columns</samp></dt>
|
|
<dd><p>Set log2 of the number of columns of tiles to use (0-4).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">svtav1-params</samp></dt>
|
|
<dd><p>Set SVT-AV1 options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated
|
|
by ":". See the SVT-AV1 encoder user guide for a list of accepted parameters.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libjxl">
|
|
<h3 class="section">9.9 libjxl</h3>
|
|
|
|
<p>libjxl JPEG XL encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libjxl headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libjxl</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-28" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-28">
|
|
<h4 class="subsection">9.9.1 Options</h4>
|
|
|
|
<p>The libjxl wrapper supports the following options:
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">distance</samp></dt>
|
|
<dd><p>Set the target Butteraugli distance. This is a quality setting: lower
|
|
distance yields higher quality, with distance=1.0 roughly comparable to
|
|
libjpeg Quality 90 for photographic content. Setting distance=0.0 yields
|
|
true lossless encoding. Valid values range between 0.0 and 15.0, and sane
|
|
values rarely exceed 5.0. Setting distance=0.1 usually attains
|
|
transparency for most input. The default is 1.0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">effort</samp></dt>
|
|
<dd><p>Set the encoding effort used. Higher effort values produce more consistent
|
|
quality and usually produces a better quality/bpp curve, at the cost of
|
|
more CPU time required. Valid values range from 1 to 9, and the default is 7.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">modular</samp></dt>
|
|
<dd><p>Force the encoder to use Modular mode instead of choosing automatically. The
|
|
default is to use VarDCT for lossy encoding and Modular for lossless. VarDCT
|
|
is generally superior to Modular for lossy encoding but does not support
|
|
lossless encoding.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libkvazaar">
|
|
<h3 class="section">9.10 libkvazaar</h3>
|
|
|
|
<p>Kvazaar H.265/HEVC encoder.
|
|
</p>
|
|
<p>Requires the presence of the libkvazaar headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<samp class="option">--enable-libkvazaar</samp>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-29" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-29">
|
|
<h4 class="subsection">9.10.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set target video bitrate in bit/s and enable rate control.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">kvazaar-params</samp></dt>
|
|
<dd><p>Set kvazaar parameters as a list of <var class="var">name</var>=<var class="var">value</var> pairs separated
|
|
by commas (,). See kvazaar documentation for a list of options.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libopenh264">
|
|
<h3 class="section">9.11 libopenh264</h3>
|
|
|
|
<p>Cisco libopenh264 H.264/MPEG-4 AVC encoder wrapper.
|
|
</p>
|
|
<p>This encoder requires the presence of the libopenh264 headers and
|
|
library during configuration. You need to explicitly configure the
|
|
build with <code class="code">--enable-libopenh264</code>. The library is detected using
|
|
<code class="command">pkg-config</code>.
|
|
</p>
|
|
<p>For more information about the library see
|
|
<a class="url" href="http://www.openh264.org">http://www.openh264.org</a>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-30" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-30">
|
|
<h4 class="subsection">9.11.1 Options</h4>
|
|
|
|
<p>The following FFmpeg global options affect the configurations of the
|
|
libopenh264 encoder.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set the bitrate (as a number of bits per second).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">g</samp></dt>
|
|
<dd><p>Set the GOP size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">maxrate</samp></dt>
|
|
<dd><p>Set the max bitrate (as a number of bits per second).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">flags +global_header</samp></dt>
|
|
<dd><p>Set global header in the bitstream.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">slices</samp></dt>
|
|
<dd><p>Set the number of slices, used in parallelized encoding. Default value
|
|
is 0. This is only used when <samp class="option">slice_mode</samp> is set to
|
|
‘<samp class="samp">fixed</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">loopfilter</samp></dt>
|
|
<dd><p>Enable loop filter, if set to 1 (automatically enabled). To disable
|
|
set a value of 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Set profile restrictions. If set to the value of ‘<samp class="samp">main</samp>’ enable
|
|
CABAC (set the <code class="code">SEncParamExt.iEntropyCodingModeFlag</code> flag to 1).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_nal_size</samp></dt>
|
|
<dd><p>Set maximum NAL size in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">allow_skip_frames</samp></dt>
|
|
<dd><p>Allow skipping frames to hit the target bitrate if set to 1.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libtheora">
|
|
<h3 class="section">9.12 libtheora</h3>
|
|
|
|
<p>libtheora Theora encoder wrapper.
|
|
</p>
|
|
<p>Requires the presence of the libtheora headers and library during
|
|
configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libtheora</code>.
|
|
</p>
|
|
<p>For more information about the libtheora project see
|
|
<a class="url" href="http://www.theora.org/">http://www.theora.org/</a>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-31" accesskey="1">Options</a></li>
|
|
<li><a href="#Examples-1" accesskey="2">Examples</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-31">
|
|
<h4 class="subsection">9.12.1 Options</h4>
|
|
|
|
<p>The following global options are mapped to internal libtheora options
|
|
which affect the quality and the bitrate of the encoded stream.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Set the video bitrate in bit/s for CBR (Constant Bit Rate) mode. In
|
|
case VBR (Variable Bit Rate) mode is enabled this option is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">flags</samp></dt>
|
|
<dd><p>Used to enable constant quality mode (VBR) encoding through the
|
|
<samp class="option">qscale</samp> flag, and to enable the <code class="code">pass1</code> and <code class="code">pass2</code>
|
|
modes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">g</samp></dt>
|
|
<dd><p>Set the GOP size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">global_quality</samp></dt>
|
|
<dd><p>Set the global quality as an integer in lambda units.
|
|
</p>
|
|
<p>Only relevant when VBR mode is enabled with <code class="code">flags +qscale</code>. The
|
|
value is converted to QP units by dividing it by <code class="code">FF_QP2LAMBDA</code>,
|
|
clipped in the [0 - 10] range, and then multiplied by 6.3 to get a
|
|
value in the native libtheora range [0-63]. A higher value corresponds
|
|
to a higher quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">q</samp></dt>
|
|
<dd><p>Enable VBR mode when set to a non-negative value, and set constant
|
|
quality value as a double floating point value in QP units.
|
|
</p>
|
|
<p>The value is clipped in the [0-10] range, and then multiplied by 6.3
|
|
to get a value in the native libtheora range [0-63].
|
|
</p>
|
|
<p>This option is valid only using the <code class="command">ffmpeg</code> command-line
|
|
tool. For library interface users, use <samp class="option">global_quality</samp>.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Examples-1">
|
|
<h4 class="subsection">9.12.2 Examples</h4>
|
|
|
|
<ul class="itemize mark-bullet">
|
|
<li>Set maximum constant quality (VBR) encoding with <code class="command">ffmpeg</code>:
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i INPUT -codec:v libtheora -q:v 10 OUTPUT.ogg
|
|
</pre></div>
|
|
|
|
</li><li>Use <code class="command">ffmpeg</code> to convert a CBR 1000 kbps Theora video stream:
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i INPUT -codec:v libtheora -b:v 1000k OUTPUT.ogg
|
|
</pre></div>
|
|
</li></ul>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libvpx">
|
|
<h3 class="section">9.13 libvpx</h3>
|
|
|
|
<p>VP8/VP9 format supported through libvpx.
|
|
</p>
|
|
<p>Requires the presence of the libvpx headers and library during configuration.
|
|
You need to explicitly configure the build with <code class="code">--enable-libvpx</code>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-32" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-32">
|
|
<h4 class="subsection">9.13.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libvpx wrapper. The
|
|
<code class="command">vpxenc</code>-equivalent options or values are listed in parentheses
|
|
for easy migration.
|
|
</p>
|
|
<p>To reduce the duplication of documentation, only the private options
|
|
and some others requiring special attention are documented here. For
|
|
the documentation of the undocumented generic options, see
|
|
<a class="ref" href="#codec_002doptions">the Codec Options chapter</a>.
|
|
</p>
|
|
<p>To get more documentation of the libvpx options, invoke the command
|
|
<code class="command">ffmpeg -h encoder=libvpx</code>, <code class="command">ffmpeg -h encoder=libvpx-vp9</code> or
|
|
<code class="command">vpxenc --help</code>. Further information is available in the libvpx API
|
|
documentation.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">target-bitrate</em>)</samp></dt>
|
|
<dd><p>Set bitrate in bits/s. Note that FFmpeg’s <samp class="option">b</samp> option is
|
|
expressed in bits/s, while <code class="command">vpxenc</code>’s <samp class="option">target-bitrate</samp> is in
|
|
kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">g (<em class="emph">kf-max-dist</em>)</samp></dt>
|
|
<dt><samp class="option">keyint_min (<em class="emph">kf-min-dist</em>)</samp></dt>
|
|
<dt><samp class="option">qmin (<em class="emph">min-q</em>)</samp></dt>
|
|
<dd><p>Minimum (Best Quality) Quantizer.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmax (<em class="emph">max-q</em>)</samp></dt>
|
|
<dd><p>Maximum (Worst Quality) Quantizer.
|
|
Can be changed per-frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bufsize (<em class="emph">buf-sz</em>, <em class="emph">buf-optimal-sz</em>)</samp></dt>
|
|
<dd><p>Set ratecontrol buffer size (in bits). Note <code class="command">vpxenc</code>’s options are
|
|
specified in milliseconds, the libvpx wrapper converts this value as follows:
|
|
<code class="code">buf-sz = bufsize * 1000 / bitrate</code>,
|
|
<code class="code">buf-optimal-sz = bufsize * 1000 / bitrate * 5 / 6</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">rc_init_occupancy (<em class="emph">buf-initial-sz</em>)</samp></dt>
|
|
<dd><p>Set number of bits which should be loaded into the rc buffer before decoding
|
|
starts. Note <code class="command">vpxenc</code>’s option is specified in milliseconds, the libvpx
|
|
wrapper converts this value as follows:
|
|
<code class="code">rc_init_occupancy * 1000 / bitrate</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">undershoot-pct</samp></dt>
|
|
<dd><p>Set datarate undershoot (min) percentage of the target bitrate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">overshoot-pct</samp></dt>
|
|
<dd><p>Set datarate overshoot (max) percentage of the target bitrate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">skip_threshold (<em class="emph">drop-frame</em>)</samp></dt>
|
|
<dt><samp class="option">qcomp (<em class="emph">bias-pct</em>)</samp></dt>
|
|
<dt><samp class="option">maxrate (<em class="emph">maxsection-pct</em>)</samp></dt>
|
|
<dd><p>Set GOP max bitrate in bits/s. Note <code class="command">vpxenc</code>’s option is specified as a
|
|
percentage of the target bitrate, the libvpx wrapper converts this value as
|
|
follows: <code class="code">(maxrate * 100 / bitrate)</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minrate (<em class="emph">minsection-pct</em>)</samp></dt>
|
|
<dd><p>Set GOP min bitrate in bits/s. Note <code class="command">vpxenc</code>’s option is specified as a
|
|
percentage of the target bitrate, the libvpx wrapper converts this value as
|
|
follows: <code class="code">(minrate * 100 / bitrate)</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">minrate, maxrate, b <em class="emph">end-usage=cbr</em></samp></dt>
|
|
<dd><p><code class="code">(minrate == maxrate == bitrate)</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf (<em class="emph">end-usage=cq</em>, <em class="emph">cq-level</em>)</samp></dt>
|
|
<dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">psnr (<em class="emph">psnr</em>)</samp>’</dt>
|
|
<dt>‘<samp class="samp">ssim (<em class="emph">ssim</em>)</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">quality, deadline (<em class="emph">deadline</em>)</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">best</samp>’</dt>
|
|
<dd><p>Use best quality deadline. Poorly named and quite slow, this option should be
|
|
avoided as it may give worse quality output than good.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">good</samp>’</dt>
|
|
<dd><p>Use good quality deadline. This is a good trade-off between speed and quality
|
|
when used with the <samp class="option">cpu-used</samp> option.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">realtime</samp>’</dt>
|
|
<dd><p>Use realtime quality deadline.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">speed, cpu-used (<em class="emph">cpu-used</em>)</samp></dt>
|
|
<dd><p>Set quality/speed ratio modifier. Higher values speed up the encode at the cost
|
|
of quality.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">nr (<em class="emph">noise-sensitivity</em>)</samp></dt>
|
|
<dt><samp class="option">static-thresh</samp></dt>
|
|
<dd><p>Set a change threshold on blocks below which they will be skipped by the
|
|
encoder.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">slices (<em class="emph">token-parts</em>)</samp></dt>
|
|
<dd><p>Note that FFmpeg’s <samp class="option">slices</samp> option gives the total number of partitions,
|
|
while <code class="command">vpxenc</code>’s <samp class="option">token-parts</samp> is given as
|
|
<code class="code">log2(partitions)</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max-intra-rate</samp></dt>
|
|
<dd><p>Set maximum I-frame bitrate as a percentage of the target bitrate. A value of 0
|
|
means unlimited.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">force_key_frames</samp></dt>
|
|
<dd><p><code class="code">VPX_EFLAG_FORCE_KF</code>
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">Alternate reference frame related</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt><samp class="option">auto-alt-ref</samp></dt>
|
|
<dd><p>Enable use of alternate reference frames (2-pass only).
|
|
Values greater than 1 enable multi-layer alternate reference frames (VP9 only).
|
|
</p></dd>
|
|
<dt><samp class="option">arnr-maxframes</samp></dt>
|
|
<dd><p>Set altref noise reduction max frame count.
|
|
</p></dd>
|
|
<dt><samp class="option">arnr-type</samp></dt>
|
|
<dd><p>Set altref noise reduction filter type: backward, forward, centered.
|
|
</p></dd>
|
|
<dt><samp class="option">arnr-strength</samp></dt>
|
|
<dd><p>Set altref noise reduction filter strength.
|
|
</p></dd>
|
|
<dt><samp class="option">rc-lookahead, lag-in-frames (<em class="emph">lag-in-frames</em>)</samp></dt>
|
|
<dd><p>Set number of frames to look ahead for frametype and ratecontrol.
|
|
</p></dd>
|
|
<dt><samp class="option">min-gf-interval</samp></dt>
|
|
<dd><p>Set minimum golden/alternate reference frame interval (VP9 only).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">error-resilient</samp></dt>
|
|
<dd><p>Enable error resiliency features.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sharpness <var class="var">integer</var></samp></dt>
|
|
<dd><p>Increase sharpness at the expense of lower PSNR.
|
|
The valid range is [0, 7].
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ts-parameters</samp></dt>
|
|
<dd><p>Sets the temporal scalability configuration using a :-separated list of
|
|
key=value pairs. For example, to specify temporal scalability parameters
|
|
with <code class="code">ffmpeg</code>:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i INPUT -c:v libvpx -ts-parameters ts_number_layers=3:\
|
|
ts_target_bitrate=250,500,1000:ts_rate_decimator=4,2,1:\
|
|
ts_periodicity=4:ts_layer_id=0,2,1,2:ts_layering_mode=3 OUTPUT
|
|
</pre></div>
|
|
<p>Below is a brief explanation of each of the parameters, please
|
|
refer to <code class="code">struct vpx_codec_enc_cfg</code> in <code class="code">vpx/vpx_encoder.h</code> for more
|
|
details.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">ts_number_layers</samp></dt>
|
|
<dd><p>Number of temporal coding layers.
|
|
</p></dd>
|
|
<dt><samp class="option">ts_target_bitrate</samp></dt>
|
|
<dd><p>Target bitrate for each temporal layer (in kbps).
|
|
(bitrate should be inclusive of the lower temporal layer).
|
|
</p></dd>
|
|
<dt><samp class="option">ts_rate_decimator</samp></dt>
|
|
<dd><p>Frame rate decimation factor for each temporal layer.
|
|
</p></dd>
|
|
<dt><samp class="option">ts_periodicity</samp></dt>
|
|
<dd><p>Length of the sequence defining frame temporal layer membership.
|
|
</p></dd>
|
|
<dt><samp class="option">ts_layer_id</samp></dt>
|
|
<dd><p>Template defining the membership of frames to temporal layers.
|
|
</p></dd>
|
|
<dt><samp class="option">ts_layering_mode</samp></dt>
|
|
<dd><p>(optional) Selecting the temporal structure from a set of pre-defined temporal layering modes.
|
|
Currently supports the following options.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dd><p>No temporal layering flags are provided internally,
|
|
relies on flags being passed in using <code class="code">metadata</code> field in <code class="code">AVFrame</code>
|
|
with following keys.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">vp8-flags</samp></dt>
|
|
<dd><p>Sets the flags passed into the encoder to indicate the referencing scheme for
|
|
the current frame.
|
|
Refer to function <code class="code">vpx_codec_encode</code> in <code class="code">vpx/vpx_encoder.h</code> for more
|
|
details.
|
|
</p></dd>
|
|
<dt><samp class="option">temporal_id</samp></dt>
|
|
<dd><p>Explicitly sets the temporal id of the current frame to encode.
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
<dt><samp class="option">2</samp></dt>
|
|
<dd><p>Two temporal layers. 0-1...
|
|
</p></dd>
|
|
<dt><samp class="option">3</samp></dt>
|
|
<dd><p>Three temporal layers. 0-2-1-2...; with single reference frame.
|
|
</p></dd>
|
|
<dt><samp class="option">4</samp></dt>
|
|
<dd><p>Same as option "3", except there is a dependency between
|
|
the two temporal layer 2 frames within the temporal period.
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">VP9-specific options</samp></dt>
|
|
<dd><dl class="table">
|
|
<dt><samp class="option">lossless</samp></dt>
|
|
<dd><p>Enable lossless mode.
|
|
</p></dd>
|
|
<dt><samp class="option">tile-columns</samp></dt>
|
|
<dd><p>Set number of tile columns to use. Note this is given as
|
|
<code class="code">log2(tile_columns)</code>. For example, 8 tile columns would be requested by
|
|
setting the <samp class="option">tile-columns</samp> option to 3.
|
|
</p></dd>
|
|
<dt><samp class="option">tile-rows</samp></dt>
|
|
<dd><p>Set number of tile rows to use. Note this is given as <code class="code">log2(tile_rows)</code>.
|
|
For example, 4 tile rows would be requested by setting the <samp class="option">tile-rows</samp>
|
|
option to 2.
|
|
</p></dd>
|
|
<dt><samp class="option">frame-parallel</samp></dt>
|
|
<dd><p>Enable frame parallel decodability features.
|
|
</p></dd>
|
|
<dt><samp class="option">aq-mode</samp></dt>
|
|
<dd><p>Set adaptive quantization mode (0: off (default), 1: variance 2: complexity, 3:
|
|
cyclic refresh, 4: equator360).
|
|
</p></dd>
|
|
<dt><samp class="option">colorspace <em class="emph">color-space</em></samp></dt>
|
|
<dd><p>Set input color space. The VP9 bitstream supports signaling the following
|
|
colorspaces:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">‘<samp class="samp">rgb</samp>’ <em class="emph">sRGB</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">bt709</samp>’ <em class="emph">bt709</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">unspecified</samp>’ <em class="emph">unknown</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">bt470bg</samp>’ <em class="emph">bt601</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">smpte170m</samp>’ <em class="emph">smpte170</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">smpte240m</samp>’ <em class="emph">smpte240</em></samp></dt>
|
|
<dt><samp class="option">‘<samp class="samp">bt2020_ncl</samp>’ <em class="emph">bt2020</em></samp></dt>
|
|
</dl>
|
|
</dd>
|
|
<dt><samp class="option">row-mt <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enable row based multi-threading.
|
|
</p></dd>
|
|
<dt><samp class="option">tune-content</samp></dt>
|
|
<dd><p>Set content type: default (0), screen (1), film (2).
|
|
</p></dd>
|
|
<dt><samp class="option">corpus-complexity</samp></dt>
|
|
<dd><p>Corpus VBR mode is a variant of standard VBR where the complexity distribution
|
|
midpoint is passed in rather than calculated for a specific clip or chunk.
|
|
</p>
|
|
<p>The valid range is [0, 10000]. 0 (default) uses standard VBR.
|
|
</p></dd>
|
|
<dt><samp class="option">enable-tpl <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enable temporal dependency model.
|
|
</p></dd>
|
|
<dt><samp class="option">ref-frame-config</samp></dt>
|
|
<dd><p>Using per-frame metadata, set members of the structure <code class="code">vpx_svc_ref_frame_config_t</code> in <code class="code">vpx/vp8cx.h</code> to fine-control referencing schemes and frame buffer management.
|
|
<br>Use a :-separated list of key=value pairs.
|
|
For example,
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">av_dict_set(&av_frame->metadata, "ref-frame-config", \
|
|
"rfc_update_buffer_slot=7:rfc_lst_fb_idx=0:rfc_gld_fb_idx=1:rfc_alt_fb_idx=2:rfc_reference_last=0:rfc_reference_golden=0:rfc_reference_alt_ref=0");
|
|
</pre></div>
|
|
<dl class="table">
|
|
<dt><samp class="option">rfc_update_buffer_slot</samp></dt>
|
|
<dd><p>Indicates the buffer slot number to update
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_update_last</samp></dt>
|
|
<dd><p>Indicates whether to update the LAST frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_update_golden</samp></dt>
|
|
<dd><p>Indicates whether to update GOLDEN frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_update_alt_ref</samp></dt>
|
|
<dd><p>Indicates whether to update ALT_REF frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_lst_fb_idx</samp></dt>
|
|
<dd><p>LAST frame buffer index
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_gld_fb_idx</samp></dt>
|
|
<dd><p>GOLDEN frame buffer index
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_alt_fb_idx</samp></dt>
|
|
<dd><p>ALT_REF frame buffer index
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_reference_last</samp></dt>
|
|
<dd><p>Indicates whether to reference LAST frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_reference_golden</samp></dt>
|
|
<dd><p>Indicates whether to reference GOLDEN frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_reference_alt_ref</samp></dt>
|
|
<dd><p>Indicates whether to reference ALT_REF frame
|
|
</p></dd>
|
|
<dt><samp class="option">rfc_reference_duration</samp></dt>
|
|
<dd><p>Indicates frame duration
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>For more information about libvpx see:
|
|
<a class="url" href="http://www.webmproject.org/">http://www.webmproject.org/</a>
|
|
</p>
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libwebp">
|
|
<h3 class="section">9.14 libwebp</h3>
|
|
|
|
<p>libwebp WebP Image encoder wrapper
|
|
</p>
|
|
<p>libwebp is Google’s official encoder for WebP images. It can encode in either
|
|
lossy or lossless mode. Lossy images are essentially a wrapper around a VP8
|
|
frame. Lossless images are a separate codec developed by Google.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Pixel-Format" accesskey="1">Pixel Format</a></li>
|
|
<li><a href="#Options-33" accesskey="2">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Pixel-Format">
|
|
<h4 class="subsection">9.14.1 Pixel Format</h4>
|
|
|
|
<p>Currently, libwebp only supports YUV420 for lossy and RGB for lossless due
|
|
to limitations of the format and libwebp. Alpha is supported for either mode.
|
|
Because of API limitations, if RGB is passed in when encoding lossy or YUV is
|
|
passed in for encoding lossless, the pixel format will automatically be
|
|
converted using functions from libwebp. This is not ideal and is done only for
|
|
convenience.
|
|
</p>
|
|
</div>
|
|
<div class="subsection-level-extent" id="Options-33">
|
|
<h4 class="subsection">9.14.2 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">-lossless <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Enables/Disables use of lossless mode. Default is 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-compression_level <var class="var">integer</var></samp></dt>
|
|
<dd><p>For lossy, this is a quality/speed tradeoff. Higher values give better quality
|
|
for a given size at the cost of increased encoding time. For lossless, this is
|
|
a size/speed tradeoff. Higher values give smaller size at the cost of increased
|
|
encoding time. More specifically, it controls the number of extra algorithms
|
|
and compression tools used, and varies the combination of these tools. This
|
|
maps to the <var class="var">method</var> option in libwebp. The valid range is 0 to 6.
|
|
Default is 4.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-quality <var class="var">float</var></samp></dt>
|
|
<dd><p>For lossy encoding, this controls image quality. For lossless encoding, this
|
|
controls the effort and time spent in compression.
|
|
Range is 0 to 100. Default is 75.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">-preset <var class="var">type</var></samp></dt>
|
|
<dd><p>Configuration preset. This does some automatic settings based on the general
|
|
type of the image.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">none</samp></dt>
|
|
<dd><p>Do not use a preset.
|
|
</p></dd>
|
|
<dt><samp class="option">default</samp></dt>
|
|
<dd><p>Use the encoder default.
|
|
</p></dd>
|
|
<dt><samp class="option">picture</samp></dt>
|
|
<dd><p>Digital picture, like portrait, inner shot
|
|
</p></dd>
|
|
<dt><samp class="option">photo</samp></dt>
|
|
<dd><p>Outdoor photograph, with natural lighting
|
|
</p></dd>
|
|
<dt><samp class="option">drawing</samp></dt>
|
|
<dd><p>Hand or line drawing, with high-contrast details
|
|
</p></dd>
|
|
<dt><samp class="option">icon</samp></dt>
|
|
<dd><p>Small-sized colorful images
|
|
</p></dd>
|
|
<dt><samp class="option">text</samp></dt>
|
|
<dd><p>Text-like
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libx264_002c-libx264rgb">
|
|
<h3 class="section">9.15 libx264, libx264rgb</h3>
|
|
|
|
<p>x264 H.264/MPEG-4 AVC encoder wrapper.
|
|
</p>
|
|
<p>This encoder requires the presence of the libx264 headers and library
|
|
during configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libx264</code>.
|
|
</p>
|
|
<p>libx264 supports an impressive number of features, including 8x8 and
|
|
4x4 adaptive spatial transform, adaptive B-frame placement, CAVLC/CABAC
|
|
entropy coding, interlacing (MBAFF), lossless mode, psy optimizations
|
|
for detail retention (adaptive quantization, psy-RD, psy-trellis).
|
|
</p>
|
|
<p>Many libx264 encoder options are mapped to FFmpeg global codec
|
|
options, while unique encoder options are provided through private
|
|
options. Additionally the <samp class="option">x264opts</samp> and <samp class="option">x264-params</samp>
|
|
private options allows one to pass a list of key=value tuples as accepted
|
|
by the libx264 <code class="code">x264_param_parse</code> function.
|
|
</p>
|
|
<p>The x264 project website is at
|
|
<a class="url" href="http://www.videolan.org/developers/x264.html">http://www.videolan.org/developers/x264.html</a>.
|
|
</p>
|
|
<p>The libx264rgb encoder is the same as libx264, except it accepts packed RGB
|
|
pixel formats as input instead of YUV.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Supported-Pixel-Formats" accesskey="1">Supported Pixel Formats</a></li>
|
|
<li><a href="#Options-34" accesskey="2">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Supported-Pixel-Formats">
|
|
<h4 class="subsection">9.15.1 Supported Pixel Formats</h4>
|
|
|
|
<p>x264 supports 8- to 10-bit color spaces. The exact bit depth is controlled at
|
|
x264’s configure time.
|
|
</p>
|
|
</div>
|
|
<div class="subsection-level-extent" id="Options-34">
|
|
<h4 class="subsection">9.15.2 Options</h4>
|
|
|
|
<p>The following options are supported by the libx264 wrapper. The
|
|
<code class="command">x264</code>-equivalent options or values are listed in parentheses
|
|
for easy migration.
|
|
</p>
|
|
<p>To reduce the duplication of documentation, only the private options
|
|
and some others requiring special attention are documented here. For
|
|
the documentation of the undocumented generic options, see
|
|
<a class="ref" href="#codec_002doptions">the Codec Options chapter</a>.
|
|
</p>
|
|
<p>To get a more accurate and extensive documentation of the libx264
|
|
options, invoke the command <code class="command">x264 --fullhelp</code> or consult
|
|
the libx264 documentation.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b (<em class="emph">bitrate</em>)</samp></dt>
|
|
<dd><p>Set bitrate in bits/s. Note that FFmpeg’s <samp class="option">b</samp> option is
|
|
expressed in bits/s, while <code class="command">x264</code>’s <samp class="option">bitrate</samp> is in
|
|
kilobits/s.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bf (<em class="emph">bframes</em>)</samp></dt>
|
|
<dt><samp class="option">g (<em class="emph">keyint</em>)</samp></dt>
|
|
<dt><samp class="option">qmin (<em class="emph">qpmin</em>)</samp></dt>
|
|
<dd><p>Minimum quantizer scale.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmax (<em class="emph">qpmax</em>)</samp></dt>
|
|
<dd><p>Maximum quantizer scale.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qdiff (<em class="emph">qpstep</em>)</samp></dt>
|
|
<dd><p>Maximum difference between quantizer scales.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qblur (<em class="emph">qblur</em>)</samp></dt>
|
|
<dd><p>Quantizer curve blur
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qcomp (<em class="emph">qcomp</em>)</samp></dt>
|
|
<dd><p>Quantizer curve compression factor
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">refs (<em class="emph">ref</em>)</samp></dt>
|
|
<dd><p>Number of reference frames each P-frame can use. The range is from <var class="var">0-16</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sc_threshold (<em class="emph">scenecut</em>)</samp></dt>
|
|
<dd><p>Sets the threshold for the scene change detection.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">trellis (<em class="emph">trellis</em>)</samp></dt>
|
|
<dd><p>Performs Trellis quantization to increase efficiency. Enabled by default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">nr (<em class="emph">nr</em>)</samp></dt>
|
|
<dt><samp class="option">me_range (<em class="emph">merange</em>)</samp></dt>
|
|
<dd><p>Maximum range of the motion search in pixels.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">me_method (<em class="emph">me</em>)</samp></dt>
|
|
<dd><p>Set motion estimation method. Possible values in the decreasing order
|
|
of speed:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">dia (<em class="emph">dia</em>)</samp>’</dt>
|
|
<dt>‘<samp class="samp">epzs (<em class="emph">dia</em>)</samp>’</dt>
|
|
<dd><p>Diamond search with radius 1 (fastest). ‘<samp class="samp">epzs</samp>’ is an alias for
|
|
‘<samp class="samp">dia</samp>’.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">hex (<em class="emph">hex</em>)</samp>’</dt>
|
|
<dd><p>Hexagonal search with radius 2.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">umh (<em class="emph">umh</em>)</samp>’</dt>
|
|
<dd><p>Uneven multi-hexagon search.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">esa (<em class="emph">esa</em>)</samp>’</dt>
|
|
<dd><p>Exhaustive search.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">tesa (<em class="emph">tesa</em>)</samp>’</dt>
|
|
<dd><p>Hadamard exhaustive search (slowest).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">forced-idr</samp></dt>
|
|
<dd><p>Normally, when forcing a I-frame type, the encoder can select any type
|
|
of I-frame. This option forces it to choose an IDR-frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">subq (<em class="emph">subme</em>)</samp></dt>
|
|
<dd><p>Sub-pixel motion estimation method.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">b_strategy (<em class="emph">b-adapt</em>)</samp></dt>
|
|
<dd><p>Adaptive B-frame placement decision algorithm. Use only on first-pass.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">keyint_min (<em class="emph">min-keyint</em>)</samp></dt>
|
|
<dd><p>Minimum GOP size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">coder</samp></dt>
|
|
<dd><p>Set entropy encoder. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">ac</samp>’</dt>
|
|
<dd><p>Enable CABAC.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">vlc</samp>’</dt>
|
|
<dd><p>Enable CAVLC and disable CABAC. It generates the same effect as
|
|
<code class="command">x264</code>’s <samp class="option">--no-cabac</samp> option.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">cmp</samp></dt>
|
|
<dd><p>Set full pixel motion estimation comparison algorithm. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">chroma</samp>’</dt>
|
|
<dd><p>Enable chroma in motion estimation.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">sad</samp>’</dt>
|
|
<dd><p>Ignore chroma in motion estimation. It generates the same effect as
|
|
<code class="command">x264</code>’s <samp class="option">--no-chroma-me</samp> option.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">threads (<em class="emph">threads</em>)</samp></dt>
|
|
<dd><p>Number of encoding threads.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">thread_type</samp></dt>
|
|
<dd><p>Set multithreading technique. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">slice</samp>’</dt>
|
|
<dd><p>Slice-based multithreading. It generates the same effect as
|
|
<code class="command">x264</code>’s <samp class="option">--sliced-threads</samp> option.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">frame</samp>’</dt>
|
|
<dd><p>Frame-based multithreading.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">flags</samp></dt>
|
|
<dd><p>Set encoding flags. It can be used to disable closed GOP and enable
|
|
open GOP by setting it to <code class="code">-cgop</code>. The result is similar to
|
|
the behavior of <code class="command">x264</code>’s <samp class="option">--open-gop</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">rc_init_occupancy (<em class="emph">vbv-init</em>)</samp></dt>
|
|
<dt><samp class="option">preset (<em class="emph">preset</em>)</samp></dt>
|
|
<dd><p>Set the encoding preset.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt>
|
|
<dd><p>Set tuning of the encoding params.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile (<em class="emph">profile</em>)</samp></dt>
|
|
<dd><p>Set profile restrictions.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">fastfirstpass</samp></dt>
|
|
<dd><p>Enable fast settings when encoding first pass, when set to 1. When set
|
|
to 0, it has the same effect of <code class="command">x264</code>’s
|
|
<samp class="option">--slow-firstpass</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf (<em class="emph">crf</em>)</samp></dt>
|
|
<dd><p>Set the quality for constant quality mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf_max (<em class="emph">crf-max</em>)</samp></dt>
|
|
<dd><p>In CRF mode, prevents VBV from lowering quality beyond this point.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qp (<em class="emph">qp</em>)</samp></dt>
|
|
<dd><p>Set constant quantization rate control method parameter.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aq-mode (<em class="emph">aq-mode</em>)</samp></dt>
|
|
<dd><p>Set AQ method. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt>
|
|
<dd><p>Disabled.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">variance (<em class="emph">1</em>)</samp>’</dt>
|
|
<dd><p>Variance AQ (complexity mask).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">autovariance (<em class="emph">2</em>)</samp>’</dt>
|
|
<dd><p>Auto-variance AQ (experimental).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">aq-strength (<em class="emph">aq-strength</em>)</samp></dt>
|
|
<dd><p>Set AQ strength, reduce blocking and blurring in flat and textured areas.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">psy</samp></dt>
|
|
<dd><p>Use psychovisual optimizations when set to 1. When set to 0, it has the
|
|
same effect as <code class="command">x264</code>’s <samp class="option">--no-psy</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">psy-rd (<em class="emph">psy-rd</em>)</samp></dt>
|
|
<dd><p>Set strength of psychovisual optimization, in
|
|
<var class="var">psy-rd</var>:<var class="var">psy-trellis</var> format.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">rc-lookahead (<em class="emph">rc-lookahead</em>)</samp></dt>
|
|
<dd><p>Set number of frames to look ahead for frametype and ratecontrol.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">weightb</samp></dt>
|
|
<dd><p>Enable weighted prediction for B-frames when set to 1. When set to 0,
|
|
it has the same effect as <code class="command">x264</code>’s <samp class="option">--no-weightb</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">weightp (<em class="emph">weightp</em>)</samp></dt>
|
|
<dd><p>Set weighted prediction method for P-frames. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt>
|
|
<dd><p>Disabled
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">simple (<em class="emph">1</em>)</samp>’</dt>
|
|
<dd><p>Enable only weighted refs
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">smart (<em class="emph">2</em>)</samp>’</dt>
|
|
<dd><p>Enable both weighted refs and duplicates
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">ssim (<em class="emph">ssim</em>)</samp></dt>
|
|
<dd><p>Enable calculation and printing SSIM stats after the encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">intra-refresh (<em class="emph">intra-refresh</em>)</samp></dt>
|
|
<dd><p>Enable the use of Periodic Intra Refresh instead of IDR frames when set
|
|
to 1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">avcintra-class (<em class="emph">class</em>)</samp></dt>
|
|
<dd><p>Configure the encoder to generate AVC-Intra.
|
|
Valid values are 50,100 and 200
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bluray-compat (<em class="emph">bluray-compat</em>)</samp></dt>
|
|
<dd><p>Configure the encoder to be compatible with the bluray standard.
|
|
It is a shorthand for setting "bluray-compat=1 force-cfr=1".
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">b-bias (<em class="emph">b-bias</em>)</samp></dt>
|
|
<dd><p>Set the influence on how often B-frames are used.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">b-pyramid (<em class="emph">b-pyramid</em>)</samp></dt>
|
|
<dd><p>Set method for keeping of some B-frames as references. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt>
|
|
<dd><p>Disabled.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">strict (<em class="emph">strict</em>)</samp>’</dt>
|
|
<dd><p>Strictly hierarchical pyramid.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">normal (<em class="emph">normal</em>)</samp>’</dt>
|
|
<dd><p>Non-strict (not Blu-ray compatible).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">mixed-refs</samp></dt>
|
|
<dd><p>Enable the use of one reference per partition, as opposed to one
|
|
reference per macroblock when set to 1. When set to 0, it has the
|
|
same effect as <code class="command">x264</code>’s <samp class="option">--no-mixed-refs</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">8x8dct</samp></dt>
|
|
<dd><p>Enable adaptive spatial transform (high profile 8x8 transform)
|
|
when set to 1. When set to 0, it has the same effect as
|
|
<code class="command">x264</code>’s <samp class="option">--no-8x8dct</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">fast-pskip</samp></dt>
|
|
<dd><p>Enable early SKIP detection on P-frames when set to 1. When set
|
|
to 0, it has the same effect as <code class="command">x264</code>’s
|
|
<samp class="option">--no-fast-pskip</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">aud (<em class="emph">aud</em>)</samp></dt>
|
|
<dd><p>Enable use of access unit delimiters when set to 1.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mbtree</samp></dt>
|
|
<dd><p>Enable use macroblock tree ratecontrol when set to 1. When set
|
|
to 0, it has the same effect as <code class="command">x264</code>’s
|
|
<samp class="option">--no-mbtree</samp> option.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">deblock (<em class="emph">deblock</em>)</samp></dt>
|
|
<dd><p>Set loop filter parameters, in <var class="var">alpha</var>:<var class="var">beta</var> form.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">cplxblur (<em class="emph">cplxblur</em>)</samp></dt>
|
|
<dd><p>Set fluctuations reduction in QP (before curve compression).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">partitions (<em class="emph">partitions</em>)</samp></dt>
|
|
<dd><p>Set partitions to consider as a comma-separated list of. Possible
|
|
values in the list:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">p8x8</samp>’</dt>
|
|
<dd><p>8x8 P-frame partition.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">p4x4</samp>’</dt>
|
|
<dd><p>4x4 P-frame partition.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">b8x8</samp>’</dt>
|
|
<dd><p>4x4 B-frame partition.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">i8x8</samp>’</dt>
|
|
<dd><p>8x8 I-frame partition.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">i4x4</samp>’</dt>
|
|
<dd><p>4x4 I-frame partition.
|
|
(Enabling ‘<samp class="samp">p4x4</samp>’ requires ‘<samp class="samp">p8x8</samp>’ to be enabled. Enabling
|
|
‘<samp class="samp">i8x8</samp>’ requires adaptive spatial transform (<samp class="option">8x8dct</samp>
|
|
option) to be enabled.)
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt>
|
|
<dd><p>Do not consider any partitions.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">all (<em class="emph">all</em>)</samp>’</dt>
|
|
<dd><p>Consider every partition.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">direct-pred (<em class="emph">direct</em>)</samp></dt>
|
|
<dd><p>Set direct MV prediction mode. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt>
|
|
<dd><p>Disable MV prediction.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">spatial (<em class="emph">spatial</em>)</samp>’</dt>
|
|
<dd><p>Enable spatial predicting.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">temporal (<em class="emph">temporal</em>)</samp>’</dt>
|
|
<dd><p>Enable temporal predicting.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">auto (<em class="emph">auto</em>)</samp>’</dt>
|
|
<dd><p>Automatically decided.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">slice-max-size (<em class="emph">slice-max-size</em>)</samp></dt>
|
|
<dd><p>Set the limit of the size of each slice in bytes. If not specified
|
|
but RTP payload size (<samp class="option">ps</samp>) is specified, that is used.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">stats (<em class="emph">stats</em>)</samp></dt>
|
|
<dd><p>Set the file name for multi-pass stats.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">nal-hrd (<em class="emph">nal-hrd</em>)</samp></dt>
|
|
<dd><p>Set signal HRD information (requires <samp class="option">vbv-bufsize</samp> to be set).
|
|
Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt>
|
|
<dd><p>Disable HRD information signaling.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">vbr (<em class="emph">vbr</em>)</samp>’</dt>
|
|
<dd><p>Variable bit rate.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">cbr (<em class="emph">cbr</em>)</samp>’</dt>
|
|
<dd><p>Constant bit rate (not allowed in MP4 container).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">x264opts (N.A.)</samp></dt>
|
|
<dd><p>Set any x264 option, see <code class="command">x264 --fullhelp</code> for a list.
|
|
</p>
|
|
<p>Argument is a list of <var class="var">key</var>=<var class="var">value</var> couples separated by
|
|
":". In <var class="var">filter</var> and <var class="var">psy-rd</var> options that use ":" as a separator
|
|
themselves, use "," instead. They accept it as well since long ago but this
|
|
is kept undocumented for some reason.
|
|
</p>
|
|
<p>For example to specify libx264 encoding options with <code class="command">ffmpeg</code>:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i foo.mpg -c:v libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><samp class="option">a53cc <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Import closed captions (which must be ATSC compatible format) into output.
|
|
Only the mpeg2 and h264 decoders provide these. Default is 1 (on).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">udu_sei <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Import user data unregistered SEI if available into output. Default is 0 (off).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">x264-params (N.A.)</samp></dt>
|
|
<dd><p>Override the x264 configuration using a :-separated list of key=value
|
|
parameters.
|
|
</p>
|
|
<p>This option is functionally the same as the <samp class="option">x264opts</samp>, but is
|
|
duplicated for compatibility with the Libav fork.
|
|
</p>
|
|
<p>For example to specify libx264 encoding options with <code class="command">ffmpeg</code>:
|
|
</p><div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i INPUT -c:v libx264 -x264-params level=30:bframes=0:weightp=0:\
|
|
cabac=0:ref=1:vbv-maxrate=768:vbv-bufsize=2000:analyse=all:me=umh:\
|
|
no-fast-pskip=1:subq=6:8x8dct=0:trellis=0 OUTPUT
|
|
</pre></div>
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>Encoding ffpresets for common usages are provided so they can be used with the
|
|
general presets system (e.g. passing the <samp class="option">pre</samp> option).
|
|
</p>
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libx265">
|
|
<h3 class="section">9.16 libx265</h3>
|
|
|
|
<p>x265 H.265/HEVC encoder wrapper.
|
|
</p>
|
|
<p>This encoder requires the presence of the libx265 headers and library
|
|
during configuration. You need to explicitly configure the build with
|
|
<samp class="option">--enable-libx265</samp>.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-35" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-35">
|
|
<h4 class="subsection">9.16.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Sets target video bitrate.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bf</samp></dt>
|
|
<dt><samp class="option">g</samp></dt>
|
|
<dd><p>Set the GOP size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">keyint_min</samp></dt>
|
|
<dd><p>Minimum GOP size.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">refs</samp></dt>
|
|
<dd><p>Number of reference frames each P-frame can use. The range is from <var class="var">1-16</var>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">preset</samp></dt>
|
|
<dd><p>Set the x265 preset.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tune</samp></dt>
|
|
<dd><p>Set the x265 tune parameter.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Set profile restrictions.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">crf</samp></dt>
|
|
<dd><p>Set the quality for constant quality mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qp</samp></dt>
|
|
<dd><p>Set constant quantization rate control method parameter.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmin</samp></dt>
|
|
<dd><p>Minimum quantizer scale.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qmax</samp></dt>
|
|
<dd><p>Maximum quantizer scale.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qdiff</samp></dt>
|
|
<dd><p>Maximum difference between quantizer scales.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qblur</samp></dt>
|
|
<dd><p>Quantizer curve blur
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qcomp</samp></dt>
|
|
<dd><p>Quantizer curve compression factor
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">i_qfactor</samp></dt>
|
|
<dt><samp class="option">b_qfactor</samp></dt>
|
|
<dt><samp class="option">forced-idr</samp></dt>
|
|
<dd><p>Normally, when forcing a I-frame type, the encoder can select any type
|
|
of I-frame. This option forces it to choose an IDR-frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">udu_sei <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Import user data unregistered SEI if available into output. Default is 0 (off).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">x265-params</samp></dt>
|
|
<dd><p>Set x265 options using a list of <var class="var">key</var>=<var class="var">value</var> couples separated
|
|
by ":". See <code class="command">x265 --help</code> for a list of options.
|
|
</p>
|
|
<p>For example to specify libx265 encoding options with <samp class="option">-x265-params</samp>:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input -c:v libx265 -x265-params crf=26:psy-rd=1 output.mp4
|
|
</pre></div>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libxavs2">
|
|
<h3 class="section">9.17 libxavs2</h3>
|
|
|
|
<p>xavs2 AVS2-P2/IEEE1857.4 encoder wrapper.
|
|
</p>
|
|
<p>This encoder requires the presence of the libxavs2 headers and library
|
|
during configuration. You need to explicitly configure the build with
|
|
<samp class="option">--enable-libxavs2</samp>.
|
|
</p>
|
|
<p>The following standard libavcodec options are used:
|
|
</p><ul class="itemize mark-bullet">
|
|
<li><samp class="option">b</samp> / <samp class="option">bit_rate</samp>
|
|
</li><li><samp class="option">g</samp> / <samp class="option">gop_size</samp>
|
|
</li><li><samp class="option">bf</samp> / <samp class="option">max_b_frames</samp>
|
|
</li></ul>
|
|
|
|
<p>The encoder also has its own specific options:
|
|
</p><ul class="mini-toc">
|
|
<li><a href="#Options-36" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-36">
|
|
<h4 class="subsection">9.17.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">lcu_row_threads</samp></dt>
|
|
<dd><p>Set the number of parallel threads for rows from 1 to 8 (default 5).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">initial_qp</samp></dt>
|
|
<dd><p>Set the xavs2 quantization parameter from 1 to 63 (default 34). This is
|
|
used to set the initial qp for the first frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qp</samp></dt>
|
|
<dd><p>Set the xavs2 quantization parameter from 1 to 63 (default 34). This is
|
|
used to set the qp value under constant-QP mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_qp</samp></dt>
|
|
<dd><p>Set the max qp for rate control from 1 to 63 (default 55).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">min_qp</samp></dt>
|
|
<dd><p>Set the min qp for rate control from 1 to 63 (default 20).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">speed_level</samp></dt>
|
|
<dd><p>Set the Speed level from 0 to 9 (default 0). Higher is better but slower.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">log_level</samp></dt>
|
|
<dd><p>Set the log level from -1 to 3 (default 0). -1: none, 0: error,
|
|
1: warning, 2: info, 3: debug.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">xavs2-params</samp></dt>
|
|
<dd><p>Set xavs2 options using a list of <var class="var">key</var>=<var class="var">value</var> couples separated
|
|
by ":".
|
|
</p>
|
|
<p>For example to specify libxavs2 encoding options with <samp class="option">-xavs2-params</samp>:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">ffmpeg -i input -c:v libxavs2 -xavs2-params RdoqLevel=0 output.avs2
|
|
</pre></div>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="libxvid">
|
|
<h3 class="section">9.18 libxvid</h3>
|
|
|
|
<p>Xvid MPEG-4 Part 2 encoder wrapper.
|
|
</p>
|
|
<p>This encoder requires the presence of the libxvidcore headers and library
|
|
during configuration. You need to explicitly configure the build with
|
|
<code class="code">--enable-libxvid --enable-gpl</code>.
|
|
</p>
|
|
<p>The native <code class="code">mpeg4</code> encoder supports the MPEG-4 Part 2 format, so
|
|
users can encode to this format without this library.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-37" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-37">
|
|
<h4 class="subsection">9.18.1 Options</h4>
|
|
|
|
<p>The following options are supported by the libxvid wrapper. Some of
|
|
the following options are listed but are not documented, and
|
|
correspond to shared codec options. See <a class="ref" href="#codec_002doptions">the Codec
|
|
Options chapter</a> for their documentation. The other shared options
|
|
which are not listed have no effect for the libxvid encoder.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dt><samp class="option">g</samp></dt>
|
|
<dt><samp class="option">qmin</samp></dt>
|
|
<dt><samp class="option">qmax</samp></dt>
|
|
<dt><samp class="option">mpeg_quant</samp></dt>
|
|
<dt><samp class="option">threads</samp></dt>
|
|
<dt><samp class="option">bf</samp></dt>
|
|
<dt><samp class="option">b_qfactor</samp></dt>
|
|
<dt><samp class="option">b_qoffset</samp></dt>
|
|
<dt><samp class="option">flags</samp></dt>
|
|
<dd><p>Set specific encoding flags. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">mv4</samp>’</dt>
|
|
<dd><p>Use four motion vector by macroblock.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">aic</samp>’</dt>
|
|
<dd><p>Enable high quality AC prediction.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">gray</samp>’</dt>
|
|
<dd><p>Only encode grayscale.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">gmc</samp>’</dt>
|
|
<dd><p>Enable the use of global motion compensation (GMC).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">qpel</samp>’</dt>
|
|
<dd><p>Enable quarter-pixel motion compensation.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">cgop</samp>’</dt>
|
|
<dd><p>Enable closed GOP.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">global_header</samp>’</dt>
|
|
<dd><p>Place global headers in extradata instead of every keyframe.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">trellis</samp></dt>
|
|
<dt><samp class="option">me_method</samp></dt>
|
|
<dd><p>Set motion estimation method. Possible values in decreasing order of
|
|
speed and increasing order of quality:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">zero</samp>’</dt>
|
|
<dd><p>Use no motion estimation (default).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">phods</samp>’</dt>
|
|
<dt>‘<samp class="samp">x1</samp>’</dt>
|
|
<dt>‘<samp class="samp">log</samp>’</dt>
|
|
<dd><p>Enable advanced diamond zonal search for 16x16 blocks and half-pixel
|
|
refinement for 16x16 blocks. ‘<samp class="samp">x1</samp>’ and ‘<samp class="samp">log</samp>’ are aliases for
|
|
‘<samp class="samp">phods</samp>’.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">epzs</samp>’</dt>
|
|
<dd><p>Enable all of the things described above, plus advanced diamond zonal
|
|
search for 8x8 blocks, half-pixel refinement for 8x8 blocks, and motion
|
|
estimation on chroma planes.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">full</samp>’</dt>
|
|
<dd><p>Enable all of the things described above, plus extended 16x16 and 8x8
|
|
blocks search.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">mbd</samp></dt>
|
|
<dd><p>Set macroblock decision algorithm. Possible values in the increasing
|
|
order of quality:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">simple</samp>’</dt>
|
|
<dd><p>Use macroblock comparing function algorithm (default).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">bits</samp>’</dt>
|
|
<dd><p>Enable rate distortion-based half pixel and quarter pixel refinement for
|
|
16x16 blocks.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">rd</samp>’</dt>
|
|
<dd><p>Enable all of the things described above, plus rate distortion-based
|
|
half pixel and quarter pixel refinement for 8x8 blocks, and rate
|
|
distortion-based search using square pattern.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">lumi_aq</samp></dt>
|
|
<dd><p>Enable lumi masking adaptive quantization when set to 1. Default is 0
|
|
(disabled).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">variance_aq</samp></dt>
|
|
<dd><p>Enable variance adaptive quantization when set to 1. Default is 0
|
|
(disabled).
|
|
</p>
|
|
<p>When combined with <samp class="option">lumi_aq</samp>, the resulting quality will not
|
|
be better than any of the two specified individually. In other
|
|
words, the resulting quality will be the worse one of the two
|
|
effects.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">ssim</samp></dt>
|
|
<dd><p>Set structural similarity (SSIM) displaying method. Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">off</samp>’</dt>
|
|
<dd><p>Disable displaying of SSIM information.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">avg</samp>’</dt>
|
|
<dd><p>Output average SSIM at the end of encoding to stdout. The format of
|
|
showing the average SSIM is:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted">Average SSIM: %f
|
|
</pre></div>
|
|
|
|
<p>For users who are not familiar with C, %f means a float number, or
|
|
a decimal (e.g. 0.939232).
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">frame</samp>’</dt>
|
|
<dd><p>Output both per-frame SSIM data during encoding and average SSIM at
|
|
the end of encoding to stdout. The format of per-frame information
|
|
is:
|
|
</p>
|
|
<div class="example">
|
|
<pre class="example-preformatted"> SSIM: avg: %1.3f min: %1.3f max: %1.3f
|
|
</pre></div>
|
|
|
|
<p>For users who are not familiar with C, %1.3f means a float number
|
|
rounded to 3 digits after the dot (e.g. 0.932).
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">ssim_acc</samp></dt>
|
|
<dd><p>Set SSIM accuracy. Valid options are integers within the range of
|
|
0-4, while 0 gives the most accurate result and 4 computes the
|
|
fastest.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="MediaFoundation">
|
|
<h3 class="section">9.19 MediaFoundation</h3>
|
|
|
|
<p>This provides wrappers to encoders (both audio and video) in the
|
|
MediaFoundation framework. It can access both SW and HW encoders.
|
|
Video encoders can take input in either of nv12 or yuv420p form
|
|
(some encoders support both, some support only either - in practice,
|
|
nv12 is the safer choice, especially among HW encoders).
|
|
</p>
|
|
</div>
|
|
<div class="section-level-extent" id="mpeg2">
|
|
<h3 class="section">9.20 mpeg2</h3>
|
|
|
|
<p>MPEG-2 video encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-38" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-38">
|
|
<h4 class="subsection">9.20.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">profile</samp></dt>
|
|
<dd><p>Select the mpeg2 profile to encode:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">422</samp>’</dt>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
<dt>‘<samp class="samp">ss</samp>’</dt>
|
|
<dd><p>Spatially Scalable
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">snr</samp>’</dt>
|
|
<dd><p>SNR Scalable
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">simple</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">level</samp></dt>
|
|
<dd><p>Select the mpeg2 level to encode:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
<dt>‘<samp class="samp">high1440</samp>’</dt>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">low</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">seq_disp_ext <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specifies if the encoder should write a sequence_display_extension to the
|
|
output.
|
|
</p><dl class="table">
|
|
<dt><samp class="option">-1</samp></dt>
|
|
<dt><samp class="option">auto</samp></dt>
|
|
<dd><p>Decide automatically to write it or not (this is the default) by checking if
|
|
the data to be written is different from the default or unspecified values.
|
|
</p></dd>
|
|
<dt><samp class="option">0</samp></dt>
|
|
<dt><samp class="option">never</samp></dt>
|
|
<dd><p>Never write it.
|
|
</p></dd>
|
|
<dt><samp class="option">1</samp></dt>
|
|
<dt><samp class="option">always</samp></dt>
|
|
<dd><p>Always write it.
|
|
</p></dd>
|
|
</dl>
|
|
</dd>
|
|
<dt><samp class="option">video_format <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specifies the video_format written into the sequence display extension
|
|
indicating the source of the video pictures. The default is ‘<samp class="samp">unspecified</samp>’,
|
|
can be ‘<samp class="samp">component</samp>’, ‘<samp class="samp">pal</samp>’, ‘<samp class="samp">ntsc</samp>’, ‘<samp class="samp">secam</samp>’ or ‘<samp class="samp">mac</samp>’.
|
|
For maximum compatibility, use ‘<samp class="samp">component</samp>’.
|
|
</p></dd>
|
|
<dt><samp class="option">a53cc <var class="var">boolean</var></samp></dt>
|
|
<dd><p>Import closed captions (which must be ATSC compatible format) into output.
|
|
Default is 1 (on).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="png">
|
|
<h3 class="section">9.21 png</h3>
|
|
|
|
<p>PNG image encoder.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Private-options-1" accesskey="1">Private options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Private-options-1">
|
|
<h4 class="subsection">9.21.1 Private options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">dpi <var class="var">integer</var></samp></dt>
|
|
<dd><p>Set physical density of pixels, in dots per inch, unset by default
|
|
</p></dd>
|
|
<dt><samp class="option">dpm <var class="var">integer</var></samp></dt>
|
|
<dd><p>Set physical density of pixels, in dots per meter, unset by default
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="ProRes">
|
|
<h3 class="section">9.22 ProRes</h3>
|
|
|
|
<p>Apple ProRes encoder.
|
|
</p>
|
|
<p>FFmpeg contains 2 ProRes encoders, the prores-aw and prores-ks encoder.
|
|
The used encoder can be chosen with the <code class="code">-vcodec</code> option.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Private-Options-for-prores_002dks" accesskey="1">Private Options for prores-ks</a></li>
|
|
<li><a href="#Speed-considerations" accesskey="2">Speed considerations</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Private-Options-for-prores_002dks">
|
|
<h4 class="subsection">9.22.1 Private Options for prores-ks</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">profile <var class="var">integer</var></samp></dt>
|
|
<dd><p>Select the ProRes profile to encode
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">proxy</samp>’</dt>
|
|
<dt>‘<samp class="samp">lt</samp>’</dt>
|
|
<dt>‘<samp class="samp">standard</samp>’</dt>
|
|
<dt>‘<samp class="samp">hq</samp>’</dt>
|
|
<dt>‘<samp class="samp">4444</samp>’</dt>
|
|
<dt>‘<samp class="samp">4444xq</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">quant_mat <var class="var">integer</var></samp></dt>
|
|
<dd><p>Select quantization matrix.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dt>‘<samp class="samp">default</samp>’</dt>
|
|
<dt>‘<samp class="samp">proxy</samp>’</dt>
|
|
<dt>‘<samp class="samp">lt</samp>’</dt>
|
|
<dt>‘<samp class="samp">standard</samp>’</dt>
|
|
<dt>‘<samp class="samp">hq</samp>’</dt>
|
|
</dl>
|
|
<p>If set to <var class="var">auto</var>, the matrix matching the profile will be picked.
|
|
If not set, the matrix providing the highest quality, <var class="var">default</var>, will be
|
|
picked.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">bits_per_mb <var class="var">integer</var></samp></dt>
|
|
<dd><p>How many bits to allot for coding one macroblock. Different profiles use
|
|
between 200 and 2400 bits per macroblock, the maximum is 8000.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">mbs_per_slice <var class="var">integer</var></samp></dt>
|
|
<dd><p>Number of macroblocks in each slice (1-8); the default value (8)
|
|
should be good in almost all situations.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">vendor <var class="var">string</var></samp></dt>
|
|
<dd><p>Override the 4-byte vendor ID.
|
|
A custom vendor ID like <var class="var">apl0</var> would claim the stream was produced by
|
|
the Apple encoder.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">alpha_bits <var class="var">integer</var></samp></dt>
|
|
<dd><p>Specify number of bits for alpha component.
|
|
Possible values are <var class="var">0</var>, <var class="var">8</var> and <var class="var">16</var>.
|
|
Use <var class="var">0</var> to disable alpha plane coding.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Speed-considerations">
|
|
<h4 class="subsection">9.22.2 Speed considerations</h4>
|
|
|
|
<p>In the default mode of operation the encoder has to honor frame constraints
|
|
(i.e. not produce frames with size bigger than requested) while still making
|
|
output picture as good as possible.
|
|
A frame containing a lot of small details is harder to compress and the encoder
|
|
would spend more time searching for appropriate quantizers for each slice.
|
|
</p>
|
|
<p>Setting a higher <samp class="option">bits_per_mb</samp> limit will improve the speed.
|
|
</p>
|
|
<p>For the fastest encoding speed set the <samp class="option">qscale</samp> parameter (4 is the
|
|
recommended value) and do not set a size constraint.
|
|
</p>
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="QSV-Encoders">
|
|
<h3 class="section">9.23 QSV Encoders</h3>
|
|
|
|
<p>The family of Intel QuickSync Video encoders (MPEG-2, H.264, HEVC, JPEG/MJPEG,
|
|
VP9, AV1)
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Ratecontrol-Method" accesskey="1">Ratecontrol Method</a></li>
|
|
<li><a href="#Global-Options-_002d_003e-MSDK-Options" accesskey="2">Global Options -> MSDK Options</a></li>
|
|
<li><a href="#Common-Options-1" accesskey="3">Common Options</a></li>
|
|
<li><a href="#Runtime-Options" accesskey="4">Runtime Options</a></li>
|
|
<li><a href="#H264-options" accesskey="5">H264 options</a></li>
|
|
<li><a href="#HEVC-Options-1" accesskey="6">HEVC Options</a></li>
|
|
<li><a href="#MPEG2-Options" accesskey="7">MPEG2 Options</a></li>
|
|
<li><a href="#VP9-Options" accesskey="8">VP9 Options</a></li>
|
|
<li><a href="#AV1-Options" accesskey="9">AV1 Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Ratecontrol-Method">
|
|
<h4 class="subsection">9.23.1 Ratecontrol Method</h4>
|
|
<p>The ratecontrol method is selected as follows:
|
|
</p><ul class="itemize mark-bullet">
|
|
<li>When <samp class="option">global_quality</samp> is specified, a quality-based mode is used.
|
|
Specifically this means either
|
|
<ul class="itemize mark-minus">
|
|
<li><var class="var">CQP</var> - constant quantizer scale, when the <samp class="option">qscale</samp> codec flag is
|
|
also set (the <samp class="option">-qscale</samp> ffmpeg option).
|
|
|
|
</li><li><var class="var">LA_ICQ</var> - intelligent constant quality with lookahead, when the
|
|
<samp class="option">look_ahead</samp> option is also set.
|
|
|
|
</li><li><var class="var">ICQ</var> – intelligent constant quality otherwise. For the ICQ modes, global
|
|
quality range is 1 to 51, with 1 being the best quality.
|
|
</li></ul>
|
|
|
|
</li><li>Otherwise, a bitrate-based mode is used. For all of those, you should specify at
|
|
least the desired average bitrate with the <samp class="option">b</samp> option.
|
|
<ul class="itemize mark-minus">
|
|
<li><var class="var">LA</var> - VBR with lookahead, when the <samp class="option">look_ahead</samp> option is specified.
|
|
|
|
</li><li><var class="var">VCM</var> - video conferencing mode, when the <samp class="option">vcm</samp> option is set.
|
|
|
|
</li><li><var class="var">CBR</var> - constant bitrate, when <samp class="option">maxrate</samp> is specified and equal to
|
|
the average bitrate.
|
|
|
|
</li><li><var class="var">VBR</var> - variable bitrate, when <samp class="option">maxrate</samp> is specified, but is higher
|
|
than the average bitrate.
|
|
|
|
</li><li><var class="var">AVBR</var> - average VBR mode, when <samp class="option">maxrate</samp> is not specified, both
|
|
<samp class="option">avbr_accuracy</samp> and <samp class="option">avbr_convergence</samp> are set to non-zero. This
|
|
mode is available for H264 and HEVC on Windows.
|
|
</li></ul>
|
|
</li></ul>
|
|
|
|
<p>Note that depending on your system, a different mode than the one you specified
|
|
may be selected by the encoder. Set the verbosity level to <var class="var">verbose</var> or
|
|
higher to see the actual settings used by the QSV runtime.
|
|
</p>
|
|
</div>
|
|
<div class="subsection-level-extent" id="Global-Options-_002d_003e-MSDK-Options">
|
|
<h4 class="subsection">9.23.2 Global Options -> MSDK Options</h4>
|
|
<p>Additional libavcodec global options are mapped to MSDK options as follows:
|
|
</p>
|
|
<ul class="itemize mark-bullet">
|
|
<li><samp class="option">g/gop_size</samp> -> <samp class="option">GopPicSize</samp>
|
|
|
|
</li><li><samp class="option">bf/max_b_frames</samp>+1 -> <samp class="option">GopRefDist</samp>
|
|
|
|
</li><li><samp class="option">rc_init_occupancy/rc_initial_buffer_occupancy</samp> ->
|
|
<samp class="option">InitialDelayInKB</samp>
|
|
|
|
</li><li><samp class="option">slices</samp> -> <samp class="option">NumSlice</samp>
|
|
|
|
</li><li><samp class="option">refs</samp> -> <samp class="option">NumRefFrame</samp>
|
|
|
|
</li><li><samp class="option">b_strategy/b_frame_strategy</samp> -> <samp class="option">BRefType</samp>
|
|
|
|
</li><li><samp class="option">cgop/CLOSED_GOP</samp> codec flag -> <samp class="option">GopOptFlag</samp>
|
|
|
|
</li><li>For the <var class="var">CQP</var> mode, the <samp class="option">i_qfactor/i_qoffset</samp> and
|
|
<samp class="option">b_qfactor/b_qoffset</samp> set the difference between <var class="var">QPP</var> and <var class="var">QPI</var>,
|
|
and <var class="var">QPP</var> and <var class="var">QPB</var> respectively.
|
|
|
|
</li><li>Setting the <samp class="option">coder</samp> option to the value <var class="var">vlc</var> will make the H.264
|
|
encoder use CAVLC instead of CABAC.
|
|
|
|
</li></ul>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Common-Options-1">
|
|
<h4 class="subsection">9.23.3 Common Options</h4>
|
|
<p>Following options are used by all qsv encoders.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">async_depth</var></samp></dt>
|
|
<dd><p>Specifies how many asynchronous operations an application performs
|
|
before the application explicitly synchronizes the result. If zero,
|
|
the value is not specified.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">preset</var></samp></dt>
|
|
<dd><p>This option itemizes a range of choices from veryfast (best speed) to veryslow
|
|
(best quality).
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">veryfast</samp>’</dt>
|
|
<dt>‘<samp class="samp">faster</samp>’</dt>
|
|
<dt>‘<samp class="samp">fast</samp>’</dt>
|
|
<dt>‘<samp class="samp">medium</samp>’</dt>
|
|
<dt>‘<samp class="samp">slow</samp>’</dt>
|
|
<dt>‘<samp class="samp">slower</samp>’</dt>
|
|
<dt>‘<samp class="samp">veryslow</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">forced_idr</var></samp></dt>
|
|
<dd><p>Forcing I frames as IDR frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">low_power</var></samp></dt>
|
|
<dd><p>For encoders set this flag to ON to reduce power consumption and GPU usage.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="Runtime-Options">
|
|
<h4 class="subsection">9.23.4 Runtime Options</h4>
|
|
<p>Following options can be used durning qsv encoding.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">global_quality</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">i_quant_factor</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">i_quant_offset</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">b_quant_factor</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">b_quant_offset</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv and hevc_qsv.
|
|
Change these value to reset qsv codec’s qp configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv and hevc_qsv.
|
|
Change this value to reset qsv codec’s MaxFrameSize configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">gop_size</var></samp></dt>
|
|
<dd><p>Change this value to reset qsv codec’s gop configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_type</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv and hevc_qsv.
|
|
Change these value to reset qsv codec’s Intra Refresh configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">qmax</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">qmin</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">max_qp_i</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">min_qp_i</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">max_qp_p</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">min_qp_p</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">max_qp_b</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">min_qp_b</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv.
|
|
Change these value to reset qsv codec’s max/min qp configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv, hevc_qsv and av1_qsv.
|
|
Change this value to reset qsv codec’s low_delay_brc configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">framerate</var></samp></dt>
|
|
<dd><p>Change this value to reset qsv codec’s framerate configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">bit_rate</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">rc_buffer_size</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">rc_initial_buffer_occupancy</var></samp></dt>
|
|
<dt><samp class="option"><var class="var">rc_max_rate</var></samp></dt>
|
|
<dd><p>Change these value to reset qsv codec’s bitrate control configuration.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt>
|
|
<dd><p>Supported in h264_qsv and hevc_qsv.
|
|
Change this value to reset qsv codec’s pic_timing_sei configuration.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="H264-options">
|
|
<h4 class="subsection">9.23.5 H264 options</h4>
|
|
<p>These options are used by h264_qsv
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">extbrc</var></samp></dt>
|
|
<dd><p>Extended bitrate control.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">recovery_point_sei</var></samp></dt>
|
|
<dd><p>Set this flag to insert the recovery point SEI message at the beginning of every
|
|
intra refresh cycle.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">rdo</var></samp></dt>
|
|
<dd><p>Enable rate distortion optimization.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size_i</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size for I frames in bytes. If this value is set as larger
|
|
than zero, then for I frames the value set by max_frame_size is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size_p</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size for P frames in bytes. If this value is set as larger
|
|
than zero, then for P frames the value set by max_frame_size is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_slice_size</var></samp></dt>
|
|
<dd><p>Maximum encoded slice size in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">bitrate_limit</var></samp></dt>
|
|
<dd><p>Toggle bitrate limitations.
|
|
Modifies bitrate to be in the range imposed by the QSV encoder. Setting this
|
|
flag off may lead to violation of HRD conformance. Mind that specifying bitrate
|
|
below the QSV encoder range might significantly affect quality. If on this
|
|
option takes effect in non CQP modes: if bitrate is not in the range imposed
|
|
by the QSV encoder, it will be changed to be in the range.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">mbbrc</var></samp></dt>
|
|
<dd><p>Setting this flag enables macroblock level bitrate control that generally
|
|
improves subjective visual quality. Enabling this flag may have negative impact
|
|
on performance and objective visual quality metric.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt>
|
|
<dd><p>Setting this flag turns on or off LowDelayBRC feautre in qsv plugin, which provides
|
|
more accurate bitrate control to minimize the variance of bitstream size frame
|
|
by frame. Value: -1-default 0-off 1-on
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_i</var></samp></dt>
|
|
<dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag
|
|
to allow changing of frame type from P and B to I.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_b</var></samp></dt>
|
|
<dd><p>This flag controls changing of frame type from B to P.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">p_strategy</var></samp></dt>
|
|
<dd><p>Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">b_strategy</var></samp></dt>
|
|
<dd><p>This option controls usage of B frames as reference.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">dblk_idc</var></samp></dt>
|
|
<dd><p>This option disable deblocking. It has value in range 0~2.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">cavlc</var></samp></dt>
|
|
<dd><p>If set, CAVLC is used; if unset, CABAC is used for encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">vcm</var></samp></dt>
|
|
<dd><p>Video conferencing mode, please see ratecontrol method.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">idr_interval</var></samp></dt>
|
|
<dd><p>Distance (in I-frames) between IDR frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt>
|
|
<dd><p>Insert picture timing SEI with pic_struct_syntax element.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">single_sei_nal_unit</var></samp></dt>
|
|
<dd><p>Put all the SEI messages into one NALU.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_dec_frame_buffering</var></samp></dt>
|
|
<dd><p>Maximum number of frames buffered in the DPB.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">look_ahead</var></samp></dt>
|
|
<dd><p>Use VBR algorithm with look ahead.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt>
|
|
<dd><p>Depth of look ahead in number frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">look_ahead_downsampling</var></samp></dt>
|
|
<dd><p>Downscaling factor for the frames saved for the lookahead analysis.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
<dt>‘<samp class="samp">off</samp>’</dt>
|
|
<dt>‘<samp class="samp">2x</samp>’</dt>
|
|
<dt>‘<samp class="samp">4x</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_type</var></samp></dt>
|
|
<dd><p>Specifies intra refresh type. The major goal of intra refresh is improvement of
|
|
error resilience without significant impact on encoded bitstream size caused by
|
|
I frames. The SDK encoder achieves this by encoding part of each frame in
|
|
refresh cycle using intra MBs. <var class="var">none</var> means no refresh. <var class="var">vertical</var> means
|
|
vertical refresh, by column of MBs. <var class="var">horizontal</var> means horizontal refresh,
|
|
by rows of MBs. <var class="var">slice</var> means horizontal refresh by slices without
|
|
overlapping. In case of <var class="var">slice</var>, in_ref_cycle_size is ignored. To enable
|
|
intra refresh, B frame should be set to 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt>
|
|
<dd><p>Specifies number of pictures within refresh cycle starting from 2. 0 and 1 are
|
|
invalid values.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt>
|
|
<dd><p>Specifies QP difference for inserted intra MBs. This is signed value in
|
|
[-51, 51] range if target encoding bit-depth for luma samples is 8 and this
|
|
range is [-63, 63] for 10 bit-depth or [-75, 75] for 12 bit-depth respectively.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt>
|
|
<dd><p>Distance between the beginnings of the intra-refresh cycles in frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">profile</var></samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">baseline</samp>’</dt>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">a53cc</var></samp></dt>
|
|
<dd><p>Use A53 Closed Captions (if available).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">aud</var></samp></dt>
|
|
<dd><p>Insert the Access Unit Delimiter NAL.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">mfmode</var></samp></dt>
|
|
<dd><p>Multi-Frame Mode.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">off</samp>’</dt>
|
|
<dt>‘<samp class="samp">auto</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">repeat_pps</var></samp></dt>
|
|
<dd><p>Repeat pps for every frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_i</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for I frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_i</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for I frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_p</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for P frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_p</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for P frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_b</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for B frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_b</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for B frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">scenario</var></samp></dt>
|
|
<dd><p>Provides a hint to encoder about the scenario for the encoding session.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">displayremoting</samp>’</dt>
|
|
<dt>‘<samp class="samp">videoconference</samp>’</dt>
|
|
<dt>‘<samp class="samp">archive</samp>’</dt>
|
|
<dt>‘<samp class="samp">livestreaming</samp>’</dt>
|
|
<dt>‘<samp class="samp">cameracapture</samp>’</dt>
|
|
<dt>‘<samp class="samp">videosurveillance</samp>’</dt>
|
|
<dt>‘<samp class="samp">gamestreaming</samp>’</dt>
|
|
<dt>‘<samp class="samp">remotegaming</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">avbr_accuracy</var></samp></dt>
|
|
<dd><p>Accuracy of the AVBR ratecontrol (unit of tenth of percent).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">avbr_convergence</var></samp></dt>
|
|
<dd><p>Convergence of the AVBR ratecontrol (unit of 100 frames)
|
|
</p>
|
|
<p>The parameters <var class="var">avbr_accuracy</var> and <var class="var">avbr_convergence</var> are for the
|
|
average variable bitrate control (AVBR) algorithm.
|
|
The algorithm focuses on overall encoding quality while meeting the specified
|
|
bitrate, <var class="var">target_bitrate</var>, within the accuracy range <var class="var">avbr_accuracy</var>,
|
|
after a <var class="var">avbr_Convergence</var> period. This method does not follow HRD and the
|
|
instant bitrate is not capped or padded.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">skip_frame</var></samp></dt>
|
|
<dd><p>Use per-frame metadata "qsv_skip_frame" to skip frame when encoding. This option
|
|
defines the usage of this metadata.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">no_skip</samp>’</dt>
|
|
<dd><p>Frame skipping is disabled.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">insert_dummy</samp>’</dt>
|
|
<dd><p>Encoder inserts into bitstream frame where all macroblocks are encoded as
|
|
skipped.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">insert_nothing</samp>’</dt>
|
|
<dd><p>Similar to insert_dummy, but encoder inserts nothing into bitstream. The skipped
|
|
frames are still used in brc. For example, gop still include skipped frames, and
|
|
the frames after skipped frames will be larger in size.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">brc_only</samp>’</dt>
|
|
<dd><p>skip_frame metadata indicates the number of missed frames before the current
|
|
frame.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="HEVC-Options-1">
|
|
<h4 class="subsection">9.23.6 HEVC Options</h4>
|
|
<p>These options are used by hevc_qsv
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option"><var class="var">extbrc</var></samp></dt>
|
|
<dd><p>Extended bitrate control.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">recovery_point_sei</var></samp></dt>
|
|
<dd><p>Set this flag to insert the recovery point SEI message at the beginning of every
|
|
intra refresh cycle.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">rdo</var></samp></dt>
|
|
<dd><p>Enable rate distortion optimization.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size_i</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size for I frames in bytes. If this value is set as larger
|
|
than zero, then for I frames the value set by max_frame_size is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_frame_size_p</var></samp></dt>
|
|
<dd><p>Maximum encoded frame size for P frames in bytes. If this value is set as larger
|
|
than zero, then for P frames the value set by max_frame_size is ignored.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_slice_size</var></samp></dt>
|
|
<dd><p>Maximum encoded slice size in bytes.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">mbbrc</var></samp></dt>
|
|
<dd><p>Setting this flag enables macroblock level bitrate control that generally
|
|
improves subjective visual quality. Enabling this flag may have negative impact
|
|
on performance and objective visual quality metric.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt>
|
|
<dd><p>Setting this flag turns on or off LowDelayBRC feautre in qsv plugin, which provides
|
|
more accurate bitrate control to minimize the variance of bitstream size frame
|
|
by frame. Value: -1-default 0-off 1-on
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_i</var></samp></dt>
|
|
<dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag
|
|
to allow changing of frame type from P and B to I.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_b</var></samp></dt>
|
|
<dd><p>This flag controls changing of frame type from B to P.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">p_strategy</var></samp></dt>
|
|
<dd><p>Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">b_strategy</var></samp></dt>
|
|
<dd><p>This option controls usage of B frames as reference.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">dblk_idc</var></samp></dt>
|
|
<dd><p>This option disable deblocking. It has value in range 0~2.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">idr_interval</var></samp></dt>
|
|
<dd><p>Distance (in I-frames) between IDR frames.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">begin_only</samp>’</dt>
|
|
<dd><p>Output an IDR-frame only at the beginning of the stream.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">load_plugin</var></samp></dt>
|
|
<dd><p>A user plugin to load in an internal session.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">none</samp>’</dt>
|
|
<dt>‘<samp class="samp">hevc_sw</samp>’</dt>
|
|
<dt>‘<samp class="samp">hevc_hw</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">load_plugins</var></samp></dt>
|
|
<dd><p>A :-separate list of hexadecimal plugin UIDs to load in
|
|
an internal session.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt>
|
|
<dd><p>Depth of look ahead in number frames, available when extbrc option is enabled.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">profile</var></samp></dt>
|
|
<dd><p>Set the encoding profile (scc requires libmfx >= 1.32).
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">main10</samp>’</dt>
|
|
<dt>‘<samp class="samp">mainsp</samp>’</dt>
|
|
<dt>‘<samp class="samp">rext</samp>’</dt>
|
|
<dt>‘<samp class="samp">scc</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tier</var></samp></dt>
|
|
<dd><p>Set the encoding tier (only level >= 4 can support high tier).
|
|
This option only takes effect when the level option is specified.
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">gpb</var></samp></dt>
|
|
<dd><p>1: GPB (generalized P/B frame)
|
|
</p>
|
|
<p>0: regular P frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_cols</var></samp></dt>
|
|
<dd><p>Number of columns for tiled encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_rows</var></samp></dt>
|
|
<dd><p>Number of rows for tiled encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">aud</var></samp></dt>
|
|
<dd><p>Insert the Access Unit Delimiter NAL.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt>
|
|
<dd><p>Insert picture timing SEI with pic_struct_syntax element.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">transform_skip</var></samp></dt>
|
|
<dd><p>Turn this option ON to enable transformskip. It is supported on platform equal
|
|
or newer than ICL.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_type</var></samp></dt>
|
|
<dd><p>Specifies intra refresh type. The major goal of intra refresh is improvement of
|
|
error resilience without significant impact on encoded bitstream size caused by
|
|
I frames. The SDK encoder achieves this by encoding part of each frame in
|
|
refresh cycle using intra MBs. <var class="var">none</var> means no refresh. <var class="var">vertical</var> means
|
|
vertical refresh, by column of MBs. <var class="var">horizontal</var> means horizontal refresh,
|
|
by rows of MBs. <var class="var">slice</var> means horizontal refresh by slices without
|
|
overlapping. In case of <var class="var">slice</var>, in_ref_cycle_size is ignored. To enable
|
|
intra refresh, B frame should be set to 0.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt>
|
|
<dd><p>Specifies number of pictures within refresh cycle starting from 2. 0 and 1 are
|
|
invalid values.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt>
|
|
<dd><p>Specifies QP difference for inserted intra MBs. This is signed value in
|
|
[-51, 51] range if target encoding bit-depth for luma samples is 8 and this
|
|
range is [-63, 63] for 10 bit-depth or [-75, 75] for 12 bit-depth respectively.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt>
|
|
<dd><p>Distance between the beginnings of the intra-refresh cycles in frames.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_i</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for I frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_i</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for I frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_p</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for P frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_p</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for P frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">max_qp_b</var></samp></dt>
|
|
<dd><p>Maximum video quantizer scale for B frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">min_qp_b</var></samp></dt>
|
|
<dd><p>Minimum video quantizer scale for B frame.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">scenario</var></samp></dt>
|
|
<dd><p>Provides a hint to encoder about the scenario for the encoding session.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">displayremoting</samp>’</dt>
|
|
<dt>‘<samp class="samp">videoconference</samp>’</dt>
|
|
<dt>‘<samp class="samp">archive</samp>’</dt>
|
|
<dt>‘<samp class="samp">livestreaming</samp>’</dt>
|
|
<dt>‘<samp class="samp">cameracapture</samp>’</dt>
|
|
<dt>‘<samp class="samp">videosurveillance</samp>’</dt>
|
|
<dt>‘<samp class="samp">gamestreaming</samp>’</dt>
|
|
<dt>‘<samp class="samp">remotegaming</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">avbr_accuracy</var></samp></dt>
|
|
<dd><p>Accuracy of the AVBR ratecontrol (unit of tenth of percent).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">avbr_convergence</var></samp></dt>
|
|
<dd><p>Convergence of the AVBR ratecontrol (unit of 100 frames)
|
|
</p>
|
|
<p>The parameters <var class="var">avbr_accuracy</var> and <var class="var">avbr_convergence</var> are for the
|
|
average variable bitrate control (AVBR) algorithm.
|
|
The algorithm focuses on overall encoding quality while meeting the specified
|
|
bitrate, <var class="var">target_bitrate</var>, within the accuracy range <var class="var">avbr_accuracy</var>,
|
|
after a <var class="var">avbr_Convergence</var> period. This method does not follow HRD and the
|
|
instant bitrate is not capped or padded.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">skip_frame</var></samp></dt>
|
|
<dd><p>Use per-frame metadata "qsv_skip_frame" to skip frame when encoding. This option
|
|
defines the usage of this metadata.
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">no_skip</samp>’</dt>
|
|
<dd><p>Frame skipping is disabled.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">insert_dummy</samp>’</dt>
|
|
<dd><p>Encoder inserts into bitstream frame where all macroblocks are encoded as
|
|
skipped.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">insert_nothing</samp>’</dt>
|
|
<dd><p>Similar to insert_dummy, but encoder inserts nothing into bitstream. The skipped
|
|
frames are still used in brc. For example, gop still include skipped frames, and
|
|
the frames after skipped frames will be larger in size.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">brc_only</samp>’</dt>
|
|
<dd><p>skip_frame metadata indicates the number of missed frames before the current
|
|
frame.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="MPEG2-Options">
|
|
<h4 class="subsection">9.23.7 MPEG2 Options</h4>
|
|
<p>These options are used by mpeg2_qsv
|
|
</p><dl class="table">
|
|
<dt><samp class="option"><var class="var">profile</var></samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">simple</samp>’</dt>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
<dt>‘<samp class="samp">high</samp>’</dt>
|
|
</dl>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="VP9-Options">
|
|
<h4 class="subsection">9.23.8 VP9 Options</h4>
|
|
<p>These options are used by vp9_qsv
|
|
</p><dl class="table">
|
|
<dt><samp class="option"><var class="var">profile</var></samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">profile0</samp>’</dt>
|
|
<dt>‘<samp class="samp">profile1</samp>’</dt>
|
|
<dt>‘<samp class="samp">profile2</samp>’</dt>
|
|
<dt>‘<samp class="samp">profile3</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_cols</var></samp></dt>
|
|
<dd><p>Number of columns for tiled encoding (requires libmfx >= 1.29).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_rows</var></samp></dt>
|
|
<dd><p>Number of rows for tiled encoding (requires libmfx >= 1.29).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="subsection-level-extent" id="AV1-Options">
|
|
<h4 class="subsection">9.23.9 AV1 Options</h4>
|
|
<p>These options are used by av1_qsv (requires libvpl).
|
|
</p><dl class="table">
|
|
<dt><samp class="option"><var class="var">profile</var></samp></dt>
|
|
<dd><dl class="table">
|
|
<dt>‘<samp class="samp">unknown</samp>’</dt>
|
|
<dt>‘<samp class="samp">main</samp>’</dt>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_cols</var></samp></dt>
|
|
<dd><p>Number of columns for tiled encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">tile_rows</var></samp></dt>
|
|
<dd><p>Number of rows for tiled encoding.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_i</var></samp></dt>
|
|
<dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag
|
|
to allow changing of frame type from P and B to I.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">adaptive_b</var></samp></dt>
|
|
<dd><p>This flag controls changing of frame type from B to P.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">b_strategy</var></samp></dt>
|
|
<dd><p>This option controls usage of B frames as reference.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">extbrc</var></samp></dt>
|
|
<dd><p>Extended bitrate control.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt>
|
|
<dd><p>Depth of look ahead in number frames, available when extbrc option is enabled.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt>
|
|
<dd><p>Setting this flag turns on or off LowDelayBRC feautre in qsv plugin, which provides
|
|
more accurate bitrate control to minimize the variance of bitstream size frame
|
|
by frame. Value: -1-default 0-off 1-on
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_frame_size</samp></dt>
|
|
<dd><p>Set the allowed max size in bytes for each frame. If the frame size exceeds
|
|
the limitation, encoder will adjust the QP value to control the frame size.
|
|
Invalid in CQP rate control mode.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="snow">
|
|
<h3 class="section">9.24 snow</h3>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-39" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-39">
|
|
<h4 class="subsection">9.24.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">iterative_dia_size</samp></dt>
|
|
<dd><p>dia size for the iterative motion estimation
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="VAAPI-encoders">
|
|
<h3 class="section">9.25 VAAPI encoders</h3>
|
|
|
|
<p>Wrappers for hardware encoders accessible via VAAPI.
|
|
</p>
|
|
<p>These encoders only accept input in VAAPI hardware surfaces. If you have input
|
|
in software frames, use the <samp class="option">hwupload</samp> filter to upload them to the GPU.
|
|
</p>
|
|
<p>The following standard libavcodec options are used:
|
|
</p><ul class="itemize mark-bullet">
|
|
<li><samp class="option">g</samp> / <samp class="option">gop_size</samp>
|
|
</li><li><samp class="option">bf</samp> / <samp class="option">max_b_frames</samp>
|
|
</li><li><samp class="option">profile</samp>
|
|
|
|
<p>If not set, this will be determined automatically from the format of the input
|
|
frames and the profiles supported by the driver.
|
|
</p></li><li><samp class="option">level</samp>
|
|
</li><li><samp class="option">b</samp> / <samp class="option">bit_rate</samp>
|
|
</li><li><samp class="option">maxrate</samp> / <samp class="option">rc_max_rate</samp>
|
|
</li><li><samp class="option">bufsize</samp> / <samp class="option">rc_buffer_size</samp>
|
|
</li><li><samp class="option">rc_init_occupancy</samp> / <samp class="option">rc_initial_buffer_occupancy</samp>
|
|
</li><li><samp class="option">compression_level</samp>
|
|
|
|
<p>Speed / quality tradeoff: higher values are faster / worse quality.
|
|
</p></li><li><samp class="option">q</samp> / <samp class="option">global_quality</samp>
|
|
|
|
<p>Size / quality tradeoff: higher values are smaller / worse quality.
|
|
</p></li><li><samp class="option">qmin</samp>
|
|
</li><li><samp class="option">qmax</samp>
|
|
</li><li><samp class="option">i_qfactor</samp> / <samp class="option">i_quant_factor</samp>
|
|
</li><li><samp class="option">i_qoffset</samp> / <samp class="option">i_quant_offset</samp>
|
|
</li><li><samp class="option">b_qfactor</samp> / <samp class="option">b_quant_factor</samp>
|
|
</li><li><samp class="option">b_qoffset</samp> / <samp class="option">b_quant_offset</samp>
|
|
</li><li><samp class="option">slices</samp>
|
|
</li></ul>
|
|
|
|
<p>All encoders support the following options:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">low_power</samp></dt>
|
|
<dd><p>Some drivers/platforms offer a second encoder for some codecs intended to use
|
|
less power than the default encoder; setting this option will attempt to use
|
|
that encoder. Note that it may support a reduced feature set, so some other
|
|
options may not be available in this mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">idr_interval</samp></dt>
|
|
<dd><p>Set the number of normal intra frames between full-refresh (IDR) frames in
|
|
open-GOP mode. The intra frames are still IRAPs, but will not include global
|
|
headers and may have non-decodable leading pictures.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">b_depth</samp></dt>
|
|
<dd><p>Set the B-frame reference depth. When set to one (the default), all B-frames
|
|
will refer only to P- or I-frames. When set to greater values multiple layers
|
|
of B-frames will be present, frames in each layer only referring to frames in
|
|
higher layers.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">async_depth</samp></dt>
|
|
<dd><p>Maximum processing parallelism. Increase this to improve single channel
|
|
performance. This option doesn’t work if driver doesn’t implement vaSyncBuffer
|
|
function. Please make sure there are enough hw_frames allocated if a large
|
|
number of async_depth is used.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">max_frame_size</samp></dt>
|
|
<dd><p>Set the allowed max size in bytes for each frame. If the frame size exceeds
|
|
the limitation, encoder will adjust the QP value to control the frame size.
|
|
Invalid in CQP rate control mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">rc_mode</samp></dt>
|
|
<dd><p>Set the rate control mode to use. A given driver may only support a subset of
|
|
modes.
|
|
</p>
|
|
<p>Possible modes:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">auto</samp></dt>
|
|
<dd><p>Choose the mode automatically based on driver support and the other options.
|
|
This is the default.
|
|
</p></dd>
|
|
<dt><samp class="option">CQP</samp></dt>
|
|
<dd><p>Constant-quality.
|
|
</p></dd>
|
|
<dt><samp class="option">CBR</samp></dt>
|
|
<dd><p>Constant-bitrate.
|
|
</p></dd>
|
|
<dt><samp class="option">VBR</samp></dt>
|
|
<dd><p>Variable-bitrate.
|
|
</p></dd>
|
|
<dt><samp class="option">ICQ</samp></dt>
|
|
<dd><p>Intelligent constant-quality.
|
|
</p></dd>
|
|
<dt><samp class="option">QVBR</samp></dt>
|
|
<dd><p>Quality-defined variable-bitrate.
|
|
</p></dd>
|
|
<dt><samp class="option">AVBR</samp></dt>
|
|
<dd><p>Average variable bitrate.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>Each encoder also has its own specific options:
|
|
</p><dl class="table">
|
|
<dt><samp class="option">h264_vaapi</samp></dt>
|
|
<dd><p><samp class="option">profile</samp> sets the value of <em class="emph">profile_idc</em> and the <em class="emph">constraint_set*_flag</em>s.
|
|
<samp class="option">level</samp> sets the value of <em class="emph">level_idc</em>.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">coder</samp></dt>
|
|
<dd><p>Set entropy encoder (default is <em class="emph">cabac</em>). Possible values:
|
|
</p>
|
|
<dl class="table">
|
|
<dt>‘<samp class="samp">ac</samp>’</dt>
|
|
<dt>‘<samp class="samp">cabac</samp>’</dt>
|
|
<dd><p>Use CABAC.
|
|
</p>
|
|
</dd>
|
|
<dt>‘<samp class="samp">vlc</samp>’</dt>
|
|
<dt>‘<samp class="samp">cavlc</samp>’</dt>
|
|
<dd><p>Use CAVLC.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">aud</samp></dt>
|
|
<dd><p>Include access unit delimiters in the stream (not included by default).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sei</samp></dt>
|
|
<dd><p>Set SEI message types to include.
|
|
Some combination of the following values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">identifier</samp>’</dt>
|
|
<dd><p>Include a <em class="emph">user_data_unregistered</em> message containing information about
|
|
the encoder.
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">timing</samp>’</dt>
|
|
<dd><p>Include picture timing parameters (<em class="emph">buffering_period</em> and
|
|
<em class="emph">pic_timing</em> messages).
|
|
</p></dd>
|
|
<dt>‘<samp class="samp">recovery_point</samp>’</dt>
|
|
<dd><p>Include recovery points where appropriate (<em class="emph">recovery_point</em> messages).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">hevc_vaapi</samp></dt>
|
|
<dd><p><samp class="option">profile</samp> and <samp class="option">level</samp> set the values of
|
|
<em class="emph">general_profile_idc</em> and <em class="emph">general_level_idc</em> respectively.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">aud</samp></dt>
|
|
<dd><p>Include access unit delimiters in the stream (not included by default).
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tier</samp></dt>
|
|
<dd><p>Set <em class="emph">general_tier_flag</em>. This may affect the level chosen for the stream
|
|
if it is not explicitly specified.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">sei</samp></dt>
|
|
<dd><p>Set SEI message types to include.
|
|
Some combination of the following values:
|
|
</p><dl class="table">
|
|
<dt>‘<samp class="samp">hdr</samp>’</dt>
|
|
<dd><p>Include HDR metadata if the input frames have it
|
|
(<em class="emph">mastering_display_colour_volume</em> and <em class="emph">content_light_level</em>
|
|
messages).
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">tiles</samp></dt>
|
|
<dd><p>Set the number of tiles to encode the input video with, as columns x rows.
|
|
Larger numbers allow greater parallelism in both encoding and decoding, but
|
|
may decrease coding efficiency.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">mjpeg_vaapi</samp></dt>
|
|
<dd><p>Only baseline DCT encoding is supported. The encoder always uses the standard
|
|
quantisation and huffman tables - <samp class="option">global_quality</samp> scales the standard
|
|
quantisation table (range 1-100).
|
|
</p>
|
|
<p>For YUV, 4:2:0, 4:2:2 and 4:4:4 subsampling modes are supported. RGB is also
|
|
supported, and will create an RGB JPEG.
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">jfif</samp></dt>
|
|
<dd><p>Include JFIF header in each frame (not included by default).
|
|
</p></dd>
|
|
<dt><samp class="option">huffman</samp></dt>
|
|
<dd><p>Include standard huffman tables (on by default). Turning this off will save
|
|
a few hundred bytes in each output frame, but may lose compatibility with some
|
|
JPEG decoders which don’t fully handle MJPEG.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">mpeg2_vaapi</samp></dt>
|
|
<dd><p><samp class="option">profile</samp> and <samp class="option">level</samp> set the value of <em class="emph">profile_and_level_indication</em>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">vp8_vaapi</samp></dt>
|
|
<dd><p>B-frames are not supported.
|
|
</p>
|
|
<p><samp class="option">global_quality</samp> sets the <em class="emph">q_idx</em> used for non-key frames (range 0-127).
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">loop_filter_level</samp></dt>
|
|
<dt><samp class="option">loop_filter_sharpness</samp></dt>
|
|
<dd><p>Manually set the loop filter parameters.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</dd>
|
|
<dt><samp class="option">vp9_vaapi</samp></dt>
|
|
<dd><p><samp class="option">global_quality</samp> sets the <em class="emph">q_idx</em> used for P-frames (range 0-255).
|
|
</p>
|
|
<dl class="table">
|
|
<dt><samp class="option">loop_filter_level</samp></dt>
|
|
<dt><samp class="option">loop_filter_sharpness</samp></dt>
|
|
<dd><p>Manually set the loop filter parameters.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>B-frames are supported, but the output stream is always in encode order rather than display
|
|
order. If B-frames are enabled, it may be necessary to use the <samp class="option">vp9_raw_reorder</samp>
|
|
bitstream filter to modify the output stream to display frames in the correct order.
|
|
</p>
|
|
<p>Only normal frames are produced - the <samp class="option">vp9_superframe</samp> bitstream filter may be
|
|
required to produce a stream usable with all decoders.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
<div class="section-level-extent" id="vbn">
|
|
<h3 class="section">9.26 vbn</h3>
|
|
|
|
<p>Vizrt Binary Image encoder.
|
|
</p>
|
|
<p>This format is used by the broadcast vendor Vizrt for quick texture streaming.
|
|
Advanced features of the format such as LZW compression of texture data or
|
|
generation of mipmaps are not supported.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-40" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-40">
|
|
<h4 class="subsection">9.26.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">format <var class="var">string</var></samp></dt>
|
|
<dd><p>Sets the texture compression used by the VBN file. Can be <var class="var">dxt1</var>,
|
|
<var class="var">dxt5</var> or <var class="var">raw</var>. Default is <var class="var">dxt5</var>.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
</div>
|
|
<div class="section-level-extent" id="vc2">
|
|
<h3 class="section">9.27 vc2</h3>
|
|
|
|
<p>SMPTE VC-2 (previously BBC Dirac Pro). This codec was primarily aimed at
|
|
professional broadcasting but since it supports yuv420, yuv422 and yuv444 at
|
|
8 (limited range or full range), 10 or 12 bits, this makes it suitable for
|
|
other tasks which require low overhead and low compression (like screen
|
|
recording).
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-41" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-41">
|
|
<h4 class="subsection">9.27.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">b</samp></dt>
|
|
<dd><p>Sets target video bitrate. Usually that’s around 1:6 of the uncompressed
|
|
video bitrate (e.g. for 1920x1080 50fps yuv422p10 that’s around 400Mbps). Higher
|
|
values (close to the uncompressed bitrate) turn on lossless compression mode.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">field_order</samp></dt>
|
|
<dd><p>Enables field coding when set (e.g. to tt - top field first) for interlaced
|
|
inputs. Should increase compression with interlaced content as it splits the
|
|
fields and encodes each separately.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">wavelet_depth</samp></dt>
|
|
<dd><p>Sets the total amount of wavelet transforms to apply, between 1 and 5 (default).
|
|
Lower values reduce compression and quality. Less capable decoders may not be
|
|
able to handle values of <samp class="option">wavelet_depth</samp> over 3.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">wavelet_type</samp></dt>
|
|
<dd><p>Sets the transform type. Currently only <var class="var">5_3</var> (LeGall) and <var class="var">9_7</var>
|
|
(Deslauriers-Dubuc)
|
|
are implemented, with 9_7 being the one with better compression and thus
|
|
is the default.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">slice_width</samp></dt>
|
|
<dt><samp class="option">slice_height</samp></dt>
|
|
<dd><p>Sets the slice size for each slice. Larger values result in better compression.
|
|
For compatibility with other more limited decoders use <samp class="option">slice_width</samp> of
|
|
32 and <samp class="option">slice_height</samp> of 8.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">tolerance</samp></dt>
|
|
<dd><p>Sets the undershoot tolerance of the rate control system in percent. This is
|
|
to prevent an expensive search from being run.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">qm</samp></dt>
|
|
<dd><p>Sets the quantization matrix preset to use by default or when <samp class="option">wavelet_depth</samp>
|
|
is set to 5
|
|
</p><ul class="itemize mark-minus">
|
|
<li><var class="var">default</var>
|
|
Uses the default quantization matrix from the specifications, extended with
|
|
values for the fifth level. This provides a good balance between keeping detail
|
|
and omitting artifacts.
|
|
|
|
</li><li><var class="var">flat</var>
|
|
Use a completely zeroed out quantization matrix. This increases PSNR but might
|
|
reduce perception. Use in bogus benchmarks.
|
|
|
|
</li><li><var class="var">color</var>
|
|
Reduces detail but attempts to preserve color at extremely low bitrates.
|
|
</li></ul>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="Subtitles-Encoders">
|
|
<h2 class="chapter">10 Subtitles Encoders</h2>
|
|
|
|
<ul class="mini-toc">
|
|
<li><a href="#dvdsub-1" accesskey="1">dvdsub</a></li>
|
|
</ul>
|
|
<div class="section-level-extent" id="dvdsub-1">
|
|
<h3 class="section">10.1 dvdsub</h3>
|
|
|
|
<p>This codec encodes the bitmap subtitle format that is used in DVDs.
|
|
Typically they are stored in VOBSUB file pairs (*.idx + *.sub),
|
|
and they can also be used in Matroska files.
|
|
</p>
|
|
<ul class="mini-toc">
|
|
<li><a href="#Options-42" accesskey="1">Options</a></li>
|
|
</ul>
|
|
<div class="subsection-level-extent" id="Options-42">
|
|
<h4 class="subsection">10.1.1 Options</h4>
|
|
|
|
<dl class="table">
|
|
<dt><samp class="option">palette</samp></dt>
|
|
<dd><p>Specify the global palette used by the bitmaps.
|
|
</p>
|
|
<p>The format for this option is a string containing 16 24-bits hexadecimal
|
|
numbers (without 0x prefix) separated by commas, for example <code class="code">0d00ee,
|
|
ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1,
|
|
7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b</code>.
|
|
</p>
|
|
</dd>
|
|
<dt><samp class="option">even_rows_fix</samp></dt>
|
|
<dd><p>When set to 1, enable a work-around that makes the number of pixel rows
|
|
even in all subtitles. This fixes a problem with some players that
|
|
cut off the bottom row if the number is odd. The work-around just adds
|
|
a fully transparent row if needed. The overhead is low, typically
|
|
one byte per subtitle on average.
|
|
</p>
|
|
<p>By default, this work-around is disabled.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="chapter-level-extent" id="See-Also">
|
|
<h2 class="chapter">11 See Also</h2>
|
|
|
|
<p><a class="url" href="ffmpeg.html">ffmpeg</a>, <a class="url" href="ffplay.html">ffplay</a>, <a class="url" href="ffprobe.html">ffprobe</a>,
|
|
<a class="url" href="libavcodec.html">libavcodec</a>
|
|
</p>
|
|
|
|
</div>
|
|
<div class="chapter-level-extent" id="Authors">
|
|
<h2 class="chapter">12 Authors</h2>
|
|
|
|
<p>The FFmpeg developers.
|
|
</p>
|
|
<p>For details about the authorship, see the Git history of the project
|
|
(https://git.ffmpeg.org/ffmpeg), e.g. by typing the command
|
|
<code class="command">git log</code> in the FFmpeg source directory, or browsing the
|
|
online repository at <a class="url" href="https://git.ffmpeg.org/ffmpeg">https://git.ffmpeg.org/ffmpeg</a>.
|
|
</p>
|
|
<p>Maintainers for the specific components are listed in the file
|
|
<samp class="file">MAINTAINERS</samp> in the source code tree.
|
|
</p>
|
|
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
</body>
|
|
</html>
|