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diff --git a/ffmpeg1/doc/encoders.texi b/ffmpeg1/doc/encoders.texi deleted file mode 100644 index 07343eb..0000000 --- a/ffmpeg1/doc/encoders.texi +++ /dev/null @@ -1,780 +0,0 @@ -@chapter Encoders -@c man begin ENCODERS - -Encoders are configured elements in FFmpeg which allow the encoding of -multimedia streams. - -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{--enable-lib} option. You can list all -available encoders using the configure option @code{--list-encoders}. - -You can disable all the encoders with the configure option -@code{--disable-encoders} and selectively enable / disable single encoders -with the options @code{--enable-encoder=@var{ENCODER}} / -@code{--disable-encoder=@var{ENCODER}}. - -The option @code{-codecs} of the ff* tools will display the list of -enabled encoders. - -@c man end ENCODERS - -@chapter Audio Encoders -@c man begin AUDIO ENCODERS - -A description of some of the currently available audio encoders -follows. - -@section ac3 and ac3_fixed - -AC-3 audio encoders. - -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). - -The @var{ac3} encoder uses floating-point math, while the @var{ac3_fixed} -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 floating-point encoder will generally produce better -quality audio for a given bitrate. The @var{ac3_fixed} encoder is not the -default codec for any of the output formats, so it must be specified explicitly -using the option @code{-acodec ac3_fixed} in order to use it. - -@subsection AC-3 Metadata - -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. - -These parameters are described in detail in several publicly-available -documents. -@itemize -@item @uref{http://www.atsc.org/cms/standards/a_52-2010.pdf,A/52:2010 - Digital Audio Compression (AC-3) (E-AC-3) Standard} -@item @uref{http://www.atsc.org/cms/standards/a_54a_with_corr_1.pdf,A/54 - Guide to the Use of the ATSC Digital Television Standard} -@item @uref{http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/18_Metadata.Guide.pdf,Dolby Metadata Guide} -@item @uref{http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/46_DDEncodingGuidelines.pdf,Dolby Digital Professional Encoding Guidelines} -@end itemize - -@subsubsection Metadata Control Options - -@table @option - -@item -per_frame_metadata @var{boolean} -Allow Per-Frame Metadata. Specifies if the encoder should check for changing -metadata for each frame. -@table @option -@item 0 -The metadata values set at initialization will be used for every frame in the -stream. (default) -@item 1 -Metadata values can be changed before encoding each frame. -@end table - -@end table - -@subsubsection Downmix Levels - -@table @option - -@item -center_mixlev @var{level} -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: -@table @option -@item 0.707 -Apply -3dB gain -@item 0.595 -Apply -4.5dB gain (default) -@item 0.500 -Apply -6dB gain -@end table - -@item -surround_mixlev @var{level} -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: -@table @option -@item 0.707 -Apply -3dB gain -@item 0.500 -Apply -6dB gain (default) -@item 0.000 -Silence Surround Channel(s) -@end table - -@end table - -@subsubsection Audio Production Information -Audio Production Information is optional information describing the mixing -environment. Either none or both of the fields are written to the bitstream. - -@table @option - -@item -mixing_level @var{number} -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{room_type} option is not the default value, the @code{mixing_level} -option must not be -1. - -@item -room_type @var{type} -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{mixing_level} -option and the @code{room_type} option have the default values. -@table @option -@item 0 -@itemx notindicated -Not Indicated (default) -@item 1 -@itemx large -Large Room -@item 2 -@itemx small -Small Room -@end table - -@end table - -@subsubsection Other Metadata Options - -@table @option - -@item -copyright @var{boolean} -Copyright Indicator. Specifies whether a copyright exists for this audio. -@table @option -@item 0 -@itemx off -No Copyright Exists (default) -@item 1 -@itemx on -Copyright Exists -@end table - -@item -dialnorm @var{value} -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. - -@item -dsur_mode @var{mode} -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{NOT} mean the encoder will actually -apply Dolby Surround processing. -@table @option -@item 0 -@itemx notindicated -Not Indicated (default) -@item 1 -@itemx off -Not Dolby Surround Encoded -@item 2 -@itemx on -Dolby Surround Encoded -@end table - -@item -original @var{boolean} -Original Bit Stream Indicator. Specifies whether this audio is from the -original source and not a copy. -@table @option -@item 0 -@itemx off -Not Original Source -@item 1 -@itemx on -Original Source (default) -@end table - -@end table - -@subsection Extended Bitstream Information -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{center_mixlev} -and @code{surround_mixlev} options if it supports the Alternate Bit Stream -Syntax. - -@subsubsection Extended Bitstream Information - Part 1 - -@table @option - -@item -dmix_mode @var{mode} -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. -@table @option -@item 0 -@itemx notindicated -Not Indicated (default) -@item 1 -@itemx ltrt -Lt/Rt Downmix Preferred -@item 2 -@itemx loro -Lo/Ro Downmix Preferred -@end table - -@item -ltrt_cmixlev @var{level} -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. -@table @option -@item 1.414 -Apply +3dB gain -@item 1.189 -Apply +1.5dB gain -@item 1.000 -Apply 0dB gain -@item 0.841 -Apply -1.5dB gain -@item 0.707 -Apply -3.0dB gain -@item 0.595 -Apply -4.5dB gain (default) -@item 0.500 -Apply -6.0dB gain -@item 0.000 -Silence Center Channel -@end table - -@item -ltrt_surmixlev @var{level} -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. -@table @option -@item 0.841 -Apply -1.5dB gain -@item 0.707 -Apply -3.0dB gain -@item 0.595 -Apply -4.5dB gain -@item 0.500 -Apply -6.0dB gain (default) -@item 0.000 -Silence Surround Channel(s) -@end table - -@item -loro_cmixlev @var{level} -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. -@table @option -@item 1.414 -Apply +3dB gain -@item 1.189 -Apply +1.5dB gain -@item 1.000 -Apply 0dB gain -@item 0.841 -Apply -1.5dB gain -@item 0.707 -Apply -3.0dB gain -@item 0.595 -Apply -4.5dB gain (default) -@item 0.500 -Apply -6.0dB gain -@item 0.000 -Silence Center Channel -@end table - -@item -loro_surmixlev @var{level} -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. -@table @option -@item 0.841 -Apply -1.5dB gain -@item 0.707 -Apply -3.0dB gain -@item 0.595 -Apply -4.5dB gain -@item 0.500 -Apply -6.0dB gain (default) -@item 0.000 -Silence Surround Channel(s) -@end table - -@end table - -@subsubsection Extended Bitstream Information - Part 2 - -@table @option - -@item -dsurex_mode @var{mode} -Dolby Surround EX Mode. Indicates whether the stream uses Dolby Surround EX -(7.1 matrixed to 5.1). Using this option does @b{NOT} mean the encoder will actually -apply Dolby Surround EX processing. -@table @option -@item 0 -@itemx notindicated -Not Indicated (default) -@item 1 -@itemx on -Dolby Surround EX Off -@item 2 -@itemx off -Dolby Surround EX On -@end table - -@item -dheadphone_mode @var{mode} -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{NOT} mean the encoder will actually apply Dolby Headphone -processing. -@table @option -@item 0 -@itemx notindicated -Not Indicated (default) -@item 1 -@itemx on -Dolby Headphone Off -@item 2 -@itemx off -Dolby Headphone On -@end table - -@item -ad_conv_type @var{type} -A/D Converter Type. Indicates whether the audio has passed through HDCD A/D -conversion. -@table @option -@item 0 -@itemx standard -Standard A/D Converter (default) -@item 1 -@itemx hdcd -HDCD A/D Converter -@end table - -@end table - -@subsection Other AC-3 Encoding Options - -@table @option - -@item -stereo_rematrixing @var{boolean} -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. - -@end table - -@subsection Floating-Point-Only AC-3 Encoding Options - -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. - -@table @option - -@item -channel_coupling @var{boolean} -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. -@table @option -@item -1 -@itemx auto -Selected by Encoder (default) -@item 0 -@itemx off -Disable Channel Coupling -@item 1 -@itemx on -Enable Channel Coupling -@end table - -@item -cpl_start_band @var{number} -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{auto} 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. -@table @option -@item -1 -@itemx auto -Selected by Encoder (default) -@end table - -@end table - -@c man end AUDIO ENCODERS - -@chapter Video Encoders -@c man begin VIDEO ENCODERS - -A description of some of the currently available video encoders -follows. - -@section libtheora - -Theora format supported through libtheora. - -Requires the presence of the libtheora headers and library during -configuration. You need to explicitly configure the build with -@code{--enable-libtheora}. - -@subsection Options - -The following global options are mapped to internal libtheora options -which affect the quality and the bitrate of the encoded stream. - -@table @option -@item b -Set the video bitrate, only works if the @code{qscale} flag in -@option{flags} is not enabled. - -@item flags -Used to enable constant quality mode encoding through the -@option{qscale} flag, and to enable the @code{pass1} and @code{pass2} -modes. - -@item g -Set the GOP size. - -@item global_quality -Set the global quality in lambda units, only works if the -@code{qscale} flag in @option{flags} is enabled. The value is clipped -in the [0 - 10*@code{FF_QP2LAMBDA}] range, and then multiplied for 6.3 -to get a value in the native libtheora range [0-63]. A higher value -corresponds to a higher quality. - -For example, to set maximum constant quality encoding with -@command{ffmpeg}: -@example -ffmpeg -i INPUT -flags:v qscale -global_quality:v "10*QP2LAMBDA" -codec:v libtheora OUTPUT.ogg -@end example -@end table - -@section libvpx - -VP8 format supported through libvpx. - -Requires the presence of the libvpx headers and library during configuration. -You need to explicitly configure the build with @code{--enable-libvpx}. - -@subsection Options - -Mapping from FFmpeg to libvpx options with conversion notes in parentheses. - -@table @option - -@item threads -g_threads - -@item profile -g_profile - -@item vb -rc_target_bitrate - -@item g -kf_max_dist - -@item keyint_min -kf_min_dist - -@item qmin -rc_min_quantizer - -@item qmax -rc_max_quantizer - -@item bufsize, vb -rc_buf_sz -@code{(bufsize * 1000 / vb)} - -rc_buf_optimal_sz -@code{(bufsize * 1000 / vb * 5 / 6)} - -@item rc_init_occupancy, vb -rc_buf_initial_sz -@code{(rc_init_occupancy * 1000 / vb)} - -@item rc_buffer_aggressivity -rc_undershoot_pct - -@item skip_threshold -rc_dropframe_thresh - -@item qcomp -rc_2pass_vbr_bias_pct - -@item maxrate, vb -rc_2pass_vbr_maxsection_pct -@code{(maxrate * 100 / vb)} - -@item minrate, vb -rc_2pass_vbr_minsection_pct -@code{(minrate * 100 / vb)} - -@item minrate, maxrate, vb -@code{VPX_CBR} -@code{(minrate == maxrate == vb)} - -@item crf -@code{VPX_CQ}, @code{VP8E_SET_CQ_LEVEL} - -@item quality -@table @option -@item @var{best} -@code{VPX_DL_BEST_QUALITY} -@item @var{good} -@code{VPX_DL_GOOD_QUALITY} -@item @var{realtime} -@code{VPX_DL_REALTIME} -@end table - -@item speed -@code{VP8E_SET_CPUUSED} - -@item nr -@code{VP8E_SET_NOISE_SENSITIVITY} - -@item mb_threshold -@code{VP8E_SET_STATIC_THRESHOLD} - -@item slices -@code{VP8E_SET_TOKEN_PARTITIONS} - -@item max-intra-rate -@code{VP8E_SET_MAX_INTRA_BITRATE_PCT} - -@item force_key_frames -@code{VPX_EFLAG_FORCE_KF} - -@item Alternate reference frame related -@table @option -@item vp8flags altref -@code{VP8E_SET_ENABLEAUTOALTREF} -@item @var{arnr_max_frames} -@code{VP8E_SET_ARNR_MAXFRAMES} -@item @var{arnr_type} -@code{VP8E_SET_ARNR_TYPE} -@item @var{arnr_strength} -@code{VP8E_SET_ARNR_STRENGTH} -@item @var{rc_lookahead} -g_lag_in_frames -@end table - -@item vp8flags error_resilient -g_error_resilient - -@end table - -For more information about libvpx see: -@url{http://www.webmproject.org/} - -@section libx264 - -x264 H.264/MPEG-4 AVC encoder wrapper - -Requires the presence of the libx264 headers and library during -configuration. You need to explicitly configure the build with -@code{--enable-libx264}. - -x264 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). - -The FFmpeg wrapper provides a mapping for most of them using global options -that match those of the encoders and provides private options for the unique -encoder options. Additionally an expert override is provided to directly pass -a list of key=value tuples as accepted by x264_param_parse. - -@subsection Option Mapping - -The following options are supported by the x264 wrapper, the x264-equivalent -options follow the FFmpeg ones. - -@multitable @columnfractions .2 .2 -@item b @tab bitrate -FFmpeg @code{b} option is expressed in bits/s, x264 @code{bitrate} in kilobits/s. -@item bf @tab bframes -Maximum number of B-frames. -@item g @tab keyint -Maximum GOP size. -@item qmin @tab qpmin -@item qmax @tab qpmax -@item qdiff @tab qpstep -@item qblur @tab qblur -@item qcomp @tab qcomp -@item refs @tab ref -@item sc_threshold @tab scenecut -@item trellis @tab trellis -@item nr @tab nr -Noise reduction. -@item me_range @tab merange -@item me_method @tab me -@item subq @tab subme -@item b_strategy @tab b-adapt -@item keyint_min @tab keyint-min -@item coder @tab cabac -Set coder to @code{ac} to use CABAC. -@item cmp @tab chroma-me -Set to @code{chroma} to use chroma motion estimation. -@item threads @tab threads -@item thread_type @tab sliced_threads -Set to @code{slice} to use sliced threading instead of frame threading. -@item flags -cgop @tab open-gop -Set @code{-cgop} to use recovery points to close GOPs. -@item rc_init_occupancy @tab vbv-init -Initial buffer occupancy. -@end multitable - -@subsection Private Options -@table @option -@item -preset @var{string} -Set the encoding preset (cf. x264 --fullhelp). -@item -tune @var{string} -Tune the encoding params (cf. x264 --fullhelp). -@item -profile @var{string} -Set profile restrictions (cf. x264 --fullhelp). -@item -fastfirstpass @var{integer} -Use fast settings when encoding first pass. -@item -crf @var{float} -Select the quality for constant quality mode. -@item -crf_max @var{float} -In CRF mode, prevents VBV from lowering quality beyond this point. -@item -qp @var{integer} -Constant quantization parameter rate control method. -@item -aq-mode @var{integer} -AQ method - -Possible values: -@table @samp -@item none - -@item variance -Variance AQ (complexity mask). -@item autovariance -Auto-variance AQ (experimental). -@end table -@item -aq-strength @var{float} -AQ strength, reduces blocking and blurring in flat and textured areas. -@item -psy @var{integer} -Use psychovisual optimizations. -@item -psy-rd @var{string} -Strength of psychovisual optimization, in <psy-rd>:<psy-trellis> format. -@item -rc-lookahead @var{integer} -Number of frames to look ahead for frametype and ratecontrol. -@item -weightb @var{integer} -Weighted prediction for B-frames. -@item -weightp @var{integer} -Weighted prediction analysis method. - -Possible values: -@table @samp -@item none - -@item simple - -@item smart - -@end table -@item -ssim @var{integer} -Calculate and print SSIM stats. -@item -intra-refresh @var{integer} -Use Periodic Intra Refresh instead of IDR frames. -@item -b-bias @var{integer} -Influences how often B-frames are used. -@item -b-pyramid @var{integer} -Keep some B-frames as references. - -Possible values: -@table @samp -@item none - -@item strict -Strictly hierarchical pyramid. -@item normal -Non-strict (not Blu-ray compatible). -@end table -@item -mixed-refs @var{integer} -One reference per partition, as opposed to one reference per macroblock. -@item -8x8dct @var{integer} -High profile 8x8 transform. -@item -fast-pskip @var{integer} -@item -aud @var{integer} -Use access unit delimiters. -@item -mbtree @var{integer} -Use macroblock tree ratecontrol. -@item -deblock @var{string} -Loop filter parameters, in <alpha:beta> form. -@item -cplxblur @var{float} -Reduce fluctuations in QP (before curve compression). -@item -partitions @var{string} -A comma-separated list of partitions to consider, possible values: p8x8, p4x4, b8x8, i8x8, i4x4, none, all. -@item -direct-pred @var{integer} -Direct MV prediction mode - -Possible values: -@table @samp -@item none - -@item spatial - -@item temporal - -@item auto - -@end table -@item -slice-max-size @var{integer} -Limit the size of each slice in bytes. -@item -stats @var{string} -Filename for 2 pass stats. -@item -nal-hrd @var{integer} -Signal HRD information (requires vbv-bufsize; cbr not allowed in .mp4). - -Possible values: -@table @samp -@item none - -@item vbr - -@item cbr - -@end table - -@item x264opts @var{options} -Allow to set any x264 option, see @code{x264 --fullhelp} for a list. - -@var{options} is a list of @var{key}=@var{value} couples separated by -":". In @var{filter} and @var{psy-rd} 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. - -For example to specify libx264 encoding options with @command{ffmpeg}: -@example -ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv -@end example - -For more information about libx264 and the supported options see: -@url{http://www.videolan.org/developers/x264.html} - -@item -x264-params @var{string} -Override the x264 configuration using a :-separated list of key=value parameters. -@example --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 -@end example -@end table - -Encoding avpresets for common usages are provided so they can be used with the -general presets system (e.g. passing the @code{-pre} option). - -@c man end VIDEO ENCODERS |