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Merge remote-tracking branch 'TimothyGu/release/2.0' into release/2.0

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* TimothyGu/release/2.0:
  doc/encoders: add doc for AAC encoder
  doc/formats: Add documentation for 3 parameters that have been missing
  doc/encoders: improve libvo-aacenc doc
  doc/encoders: reformat and add some clarification in libtwolame doc
  doc/encoders: reformat libmp3lame doc
  doc/encoders: add libxvid doc
  doc/encoders: partially rewrite and reformat libx264 docs

Merged-by: Michael Niedermayer <michaelni@gmx.at>
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Michael Niedermayer
2013-09-23 22:31:41 +02:00
parent 211ad5042a 6911d9e1b0
commit 187297b871
2 changed files with 571 additions and 199 deletions
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doc/encoders.texi
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@@ -25,6 +25,95 @@ enabled encoders.
A description of some of the currently available audio encoders A description of some of the currently available audio encoders
follows. follows.
@anchor{aacenc}
@section aac
Advanced Audio Coding (AAC) encoder.
This encoder is an experimental FFmpeg-native AAC encoder. Currently only the
low complexity (AAC-LC) profile is supported. To use this encoder, you must set
@option{strict} option to @samp{experimental} or lower.
As this encoder is experimental, unexpected behavior may exist from time to
time. For a more stable AAC encoder, see @ref{libvo-aacenc}. However, be warned
that it has a worse quality reported by some users.
@c Comment this out until somebody writes the respective documentation.
@c See also @ref{libfaac}, @ref{libaacplus}, and @ref{libfdk-aac-enc}.
@subsection Options
@table @option
@item b
Set bit rate in bits/s. Setting this automatically activates constant bit rate
(CBR) mode.
@item q
Set quality for variable bit rate (VBR) mode. This option is valid only using
the @command{ffmpeg} command-line tool. For library interface users, use
@option{global_quality}.
@item stereo_mode
Set stereo encoding mode. Possible values:
@table @samp
@item auto
Automatically selected by the encoder.
@item ms_off
Disable middle/side encoding. This is the default.
@item ms_force
Force middle/side encoding.
@end table
@item aac_coder
Set AAC encoder coding method. Possible values:
@table @samp
@item 0
FAAC-inspired method.
This method is a simplified reimplementation of the method used in FAAC, which
sets thresholds proportional to the band energies, and then decreases all the
thresholds with quantizer steps to find the appropriate quantization with
distortion below threshold band by band.
The quality of this method is comparable to the two loop searching method
descibed below, but somewhat a little better and slower.
@item 1
Average noise to mask ratio (ANMR) trellis-based solution.
This has a theoretic best quality out of all the coding methods, but at the
cost of the slowest speed.
@item 2
Two loop searching (TLS) method.
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.
This method produces similar quality with the FAAC method and is the default.
@item 3
Constant quantizer method.
This method sets a constant quantizer for all bands. This is the fastest of all
the methods, yet produces the worst quality.
@end table
@end table
@subsection Tips and Tricks
According to some reports
(e.g. @url{http://d.hatena.ne.jp/kamedo2/20120729/1343545890}), setting the
@option{cutoff} option to 15000 Hz greatly improves the quality of the output
quality. As a result, we encourage you to do the same.
@section ac3 and ac3_fixed @section ac3 and ac3_fixed
AC-3 audio encoders. AC-3 audio encoders.
@@ -420,26 +509,36 @@ Requires the presence of the libmp3lame headers and library during
configuration. You need to explicitly configure the build with configuration. You need to explicitly configure the build with
@code{--enable-libmp3lame}. @code{--enable-libmp3lame}.
@subsection Option Mapping @subsection Options
The following options are supported by the libmp3lame wrapper, The following options are supported by the libmp3lame wrapper. The
the LAME-equivalent options follow the FFmpeg ones. @command{lame}-equivalent of the options are listed in parentheses.
@multitable @columnfractions .2 .2 @table @option
@item FFmpeg @tab LAME @item b (@emph{-b})
@item b @tab b Set bitrate expressed in bits/s for CBR. LAME @code{bitrate} is
Set bitrate expressed in bits/s, LAME @code{bitrate} is expressed in expressed in kilobits/s.
kilobits/s.
@item q @tab V @item q (@emph{-V})
Set quality setting for VBR. Set constant quality setting for VBR. This option is valid only
@item compression_level @tab q using the @command{ffmpeg} command-line tool. For library interface
Set algorithm quality. Valid arguments are integers in the 0-9 range. users, use @option{global_quality}.
@item reservoir @tab N.A.
Enable use of bit reservoir. LAME has this enabled by default. @item compression_level (@emph{-q})
@item joint_stereo @tab -m j 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.
@item reservoir
Enable use of bit reservoir when set to 1. Default value is 1. LAME
has this enabled by default, but can be overriden by use
@option{--nores} option.
@item joint_stereo (@emph{-m j})
Enable the encoder to use (on a frame by frame basis) either L/R Enable the encoder to use (on a frame by frame basis) either L/R
stereo or mid/side stereo. stereo or mid/side stereo. Default value is 1.
@end multitable
@end table
@section libopencore-amrnb @section libopencore-amrnb
@@ -486,24 +585,26 @@ Requires the presence of the libtwolame headers and library during
configuration. You need to explicitly configure the build with configuration. You need to explicitly configure the build with
@code{--enable-libtwolame}. @code{--enable-libtwolame}.
@subsection Options Mapping @subsection Options
The following options are supported by the libtwolame wrapper. The The following options are supported by the libtwolame wrapper. The
TwoLAME-equivalent options follow the FFmpeg ones and are in @command{twolame}-equivalent options follow the FFmpeg ones and are in
parentheses. parentheses.
@table @option @table @option
@item b @item b (@emph{-b})
(b) Set bitrate in bits/s. Note that FFmpeg @code{b} option is Set bitrate expressed in bits/s for CBR. @command{twolame} @option{b}
expressed in bits/s, twolame @code{b} in kilobits/s. The default option is expressed in kilobits/s. Default value is 128k.
value is 128k.
@item q @item q (@emph{-V})
(V) Set quality for experimental VBR support. Maximum value range is Set quality for experimental VBR support. Maximum value range is
from -50 to 50, useful range is from -10 to 10. 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
@command{ffmpeg} command-line tool. For library interface users,
use @option{global_quality}.
@item mode @item mode (@emph{--mode})
(mode) Set MPEG mode. Possible values: Set the mode of the resulting audio. Possible values:
@table @samp @table @samp
@item auto @item auto
@@ -518,29 +619,30 @@ Dual channel
Mono Mono
@end table @end table
@item psymodel @item psymodel (@emph{--psyc-mode})
(psyc-mode) Set psychoacoustic model to use in encoding. The argument Set psychoacoustic model to use in encoding. The argument must be
must be an integer between -1 and 4, inclusive. The higher the value, an integer between -1 and 4, inclusive. The higher the value, the
the better the quality. The default value is 3. better the quality. The default value is 3.
@item energy_levels @item energy_levels (@emph{--energy})
(energy) Enable energy levels extensions when set to 1. The default Enable energy levels extensions when set to 1. The default value is
value is 0 (disabled). 0 (disabled).
@item error_protection @item error_protection (@emph{--protect})
(protect) Enable CRC error protection when set to 1. The default value Enable CRC error protection when set to 1. The default value is 0
is 0 (disabled). (disabled).
@item copyright @item copyright (@emph{--copyright})
(copyright) Set MPEG audio copyright flag when set to 1. The default Set MPEG audio copyright flag when set to 1. The default value is 0
value is 0 (disabled). (disabled).
@item original @item original (@emph{--original})
(original) Set MPEG audio original flag when set to 1. The default Set MPEG audio original flag when set to 1. The default value is 0
value is 0 (disabled). (disabled).
@end table @end table
@anchor{libvo-aacenc}
@section libvo-aacenc @section libvo-aacenc
VisualOn AAC encoder. VisualOn AAC encoder.
@@ -549,16 +651,19 @@ Requires the presence of the libvo-aacenc headers and library during
configuration. You need to explicitly configure the build with configuration. You need to explicitly configure the build with
@code{--enable-libvo-aacenc --enable-version3}. @code{--enable-libvo-aacenc --enable-version3}.
This encoder is considered to be worse than the
@ref{aacenc,,native experimental FFmpeg AAC encoder}, according to
multiple sources.
@subsection Options @subsection Options
The VisualOn AAC encoder only support encoding AAC-LC and up to 2 The VisualOn AAC encoder only support encoding AAC-LC and up to 2
channels. It is also CBR-only. It is considered to be worse than the channels. It is also CBR-only.
native experimental FFmpeg AAC encoder.
@table @option @table @option
@item b @item b
Bitrate. Set bit rate in bits/s.
@end table @end table
@@ -873,178 +978,318 @@ For more information about libvpx see:
x264 H.264/MPEG-4 AVC encoder wrapper. x264 H.264/MPEG-4 AVC encoder wrapper.
Requires the presence of the libx264 headers and library during This encoder requires the presence of the libx264 headers and library
configuration. You need to explicitly configure the build with during configuration. You need to explicitly configure the build with
@code{--enable-libx264}. @code{--enable-libx264}.
x264 supports an impressive number of features, including 8x8 and 4x4 adaptive libx264 supports an impressive number of features, including 8x8 and
spatial transform, adaptive B-frame placement, CAVLC/CABAC entropy coding, 4x4 adaptive spatial transform, adaptive B-frame placement, CAVLC/CABAC
interlacing (MBAFF), lossless mode, psy optimizations for detail retention entropy coding, interlacing (MBAFF), lossless mode, psy optimizations
(adaptive quantization, psy-RD, psy-trellis). for detail retention (adaptive quantization, psy-RD, psy-trellis).
The FFmpeg wrapper provides a mapping for most of them using global options Many libx264 encoder options are mapped to FFmpeg global codec
that match those of the encoders and provides private options for the unique options, while unique encoder options are provided through private
encoder options. Additionally an expert override is provided to directly pass options. Additionally the @option{x264opts} and @option{x264-params}
a list of key=value tuples as accepted by x264_param_parse. private options allows to pass a list of key=value tuples as accepted
by the libx264 @code{x264_param_parse} function.
@subsection Option Mapping The x264 project website is at
@url{http://www.videolan.org/developers/x264.html}.
The following options are supported by the x264 wrapper, the x264-equivalent @subsection Options
options follow the FFmpeg ones.
@multitable @columnfractions .2 .2 The following options are supported by the libx264 wrapper. The
@item b @tab bitrate @command{x264}-equivalent options or values are listed in parentheses
FFmpeg @code{b} option is expressed in bits/s, x264 @code{bitrate} in kilobits/s. for easy migration.
@item bf @tab bframes
Maximum number of B-frames. To reduce the duplication of documentation, only the private options
@item g @tab keyint and some others requiring special attention are documented here. For
Maximum GOP size. the documentation of the undocumented generic options, see
@item qmin @tab qpmin @ref{codec-options}.
@item qmax @tab qpmax
@item qdiff @tab qpstep To get a more accurate and extensive documentation of the libx264
@item qblur @tab qblur options, invoke the command @command{x264 --full-help} or consult
@item qcomp @tab qcomp the libx264 documentation.
@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 @table @option
@item -preset @var{string} @item b (@emph{bitrate})
Set the encoding preset (cf. x264 --fullhelp). Set bitrate in bits/s. Note that FFmpeg's @option{b} option is
@item -tune @var{string} expressed in bits/s, while @command{x264}'s @option{bitrate} is in
Tune the encoding params (cf. x264 --fullhelp). kilobits/s.
@item -profile @var{string}
Set profile restrictions (cf. x264 --fullhelp). @item bf (@emph{bframes})
@item -fastfirstpass @var{integer}
Use fast settings when encoding first pass. @item g (@emph{keyint})
@item -crf @var{float}
Select the quality for constant quality mode. @item qmax (@emph{qpmax})
@item -crf_max @var{float}
In CRF mode, prevents VBV from lowering quality beyond this point. @item qmin (@emph{qpmin})
@item -qp @var{integer}
Constant quantization parameter rate control method. @item qdiff (@emph{qpstep})
@item -aq-mode @var{integer}
AQ method @item qblur (@emph{qblur})
@item qcomp (@emph{qcomp})
@item refs (@emph{ref})
@item sc_threshold (@emph{scenecut})
@item trellis (@emph{trellis})
@item nr (@emph{nr})
@item me_range (@emph{merange})
@item me_method (@emph{me})
Set motion estimation method. Possible values in the decreasing order
of speed:
Possible values:
@table @samp @table @samp
@item none @item dia (@emph{dia})
@item epzs (@emph{dia})
Diamond search with radius 1 (fastest). @samp{epzs} is an alias for
@samp{dia}.
@item hex (@emph{hex})
Hexagonal search with radius 2.
@item umh (@emph{umh})
Uneven multi-hexagon search.
@item esa (@emph{esa})
Exhaustive search.
@item tesa (@emph{tesa})
Hadamard exhaustive search (slowest).
@end table
@item variance @item subq (@emph{subme})
@item b_strategy (@emph{b-adapt})
@item keyint_min (@emph{min-keyint})
@item coder
Set entropy encoder. Possible values:
@table @samp
@item ac
Enable CABAC.
@item vlc
Enable CAVLC and disable CABAC. It generates the same effect as
@command{x264}'s @option{--no-cabac} option.
@end table
@item cmp
Set full pixel motion estimation comparation algorithm. Possible values:
@table @samp
@item chroma
Enable chroma in motion estimation.
@item sad
Ignore chroma in motion estimation. It generates the same effect as
@command{x264}'s @option{--no-chroma-me} option.
@end table
@item threads (@emph{threads})
@item thread_type
Set multithreading technique. Possible values:
@table @samp
@item slice
Slice-based multithreading. It generates the same effect as
@command{x264}'s @option{--sliced-threads} option.
@item frame
Frame-based multithreading.
@end table
@item flags
Set encoding flags. It can be used to disable closed GOP and enable
open GOP by setting it to @code{-cgop}. The result is similar to
the behavior of @command{x264}'s @option{--open-gop} option.
@item rc_init_occupancy (@emph{vbv-init})
@item preset (@emph{preset})
Set the encoding preset.
@item tune (@emph{tune})
Set tuning of the encoding params.
@item profile (@emph{profile})
Set profile restrictions.
@item fastfirstpass
Enable fast settings when encoding first pass, when set to 1. When set
to 0, it has the same effect of @command{x264}'s
@option{--slow-firstpass} option.
@item crf (@emph{crf})
Set the quality for constant quality mode.
@item crf_max (@emph{crf-max})
In CRF mode, prevents VBV from lowering quality beyond this point.
@item qp (@emph{qp})
Set constant quantization rate control method parameter.
@item aq-mode (@emph{aq-mode})
Set AQ method. Possible values:
@table @samp
@item none (@emph{0})
Disabled.
@item variance (@emph{1})
Variance AQ (complexity mask). Variance AQ (complexity mask).
@item autovariance
@item autovariance (@emph{2})
Auto-variance AQ (experimental). Auto-variance AQ (experimental).
@end table @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: @item aq-strength (@emph{aq-strength})
Set AQ strength, reduce blocking and blurring in flat and textured areas.
@item psy
Use psychovisual optimizations when set to 1. When set to 0, it has the
same effect as @command{x264}'s @option{--no-psy} option.
@item psy-rd (@emph{psy-rd})
Set strength of psychovisual optimization, in
@var{psy-rd}:@var{psy-trellis} format.
@item rc-lookahead (@emph{rc-lookahead})
Set number of frames to look ahead for frametype and ratecontrol.
@item weightb
Enable weighted prediction for B-frames when set to 1. When set to 0,
it has the same effect as @command{x264}'s @option{--no-weightb} option.
@item weightp (@emph{weightp})
Set weighted prediction method for P-frames. Possible values:
@table @samp @table @samp
@item none @item none (@emph{0})
Disabled
@item simple @item simple (@emph{1})
Enable only weighted refs
@item smart @item smart (@emph{2})
Enable both weighted refs and duplicates
@end table @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: @item ssim (@emph{ssim})
Enable calculation and printing SSIM stats after the encoding.
@item intra-refresh (@emph{intra-refresh})
Enable the use of Periodic Intra Refresh instead of IDR frames when set
to 1.
@item b-bias (@emph{b-bias})
Set the influence on how often B-frames are used.
@item b-pyramid (@emph{b-pyramid})
Set method for keeping of some B-frames as references. Possible values:
@table @samp @table @samp
@item none @item none (@emph{none})
Disabled.
@item strict @item strict (@emph{strict})
Strictly hierarchical pyramid. Strictly hierarchical pyramid.
@item normal @item normal (@emph{normal})
Non-strict (not Blu-ray compatible). Non-strict (not Blu-ray compatible).
@end table @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: @item mixed-refs
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 @command{x264}'s @option{--no-mixed-refs} option.
@item 8x8dct
Enable adaptive spatial transform (high profile 8x8 transform)
when set to 1. When set to 0, it has the same effect as
@command{x264}'s @option{--no-8x8dct} option.
@item fast-pskip
Enable early SKIP detection on P-frames when set to 1. When set
to 0, it has the same effect as @command{x264}'s
@option{--no-fast-pskip} option.
@item aud (@emph{aud})
Enable use of access unit delimiters when set to 1.
@item mbtree
Enable use macroblock tree ratecontrol when set to 1. When set
to 0, it has the same effect as @command{x264}'s
@option{--no-mbtree} option.
@item deblock (@emph{deblock})
Set loop filter parameters, in @var{alpha}:@var{beta} form.
@item cplxblur (@emph{cplxblur})
Set fluctuations reduction in QP (before curve compression).
@item partitions (@emph{partitions})
Set partitions to consider as a comma-separated list of. Possible
values in the list:
@table @samp @table @samp
@item none @item p8x8
8x8 P-frame partition.
@item spatial @item p4x4
4x4 P-frame partition.
@item temporal @item b8x8
4x4 B-frame partition.
@item auto @item i8x8
8x8 I-frame partition.
@end table @item i4x4
@item -slice-max-size @var{integer} 4x4 I-frame partition.
Limit the size of each slice in bytes. (Enabling @samp{p4x4} requires @samp{p8x8} to be enabled. Enabling
@item -stats @var{string} @samp{i8x8} requires adaptive spatial transform (@option{8x8dct}
Filename for 2 pass stats. option) to be enabled.)
@item -nal-hrd @var{integer} @item none (@emph{none})
Signal HRD information (requires vbv-bufsize; cbr not allowed in .mp4). Do not consider any partitions.
@item all (@emph{all})
Possible values: Consider every partition.
@table @samp
@item none
@item vbr
@item cbr
@end table @end table
@item x264opts @var{options} @item direct-pred (@emph{direct})
Allow to set any x264 option, see @code{x264 --fullhelp} for a list. Set direct MV prediction mode. Possible values:
@var{options} is a list of @var{key}=@var{value} couples separated by @table @samp
@item none (@emph{none})
Disable MV prediction.
@item spatial (@emph{spatial})
Enable spatial predicting.
@item temporal (@emph{temporal})
Enable temporal predicting.
@item auto (@emph{auto})
Automatically decided.
@end table
@item slice-max-size (@emph{slice-max-size})
Set the limit of the size of each slice in bytes. If not specified
but RTP payload size (@option{ps}) is specified, that is used.
@item stats (@emph{stats})
Set the file name for multi-pass stats.
@item nal-hrd (@emph{nal-hrd})
Set signal HRD information (requires @option{vbv-bufsize} to be set).
Possible values:
@table @samp
@item none (@emph{none})
Disable HRD information signaling.
@item vbr (@emph{vbr})
Variable bit rate.
@item cbr (@emph{cbr})
Constant bit rate (not allowed in MP4 container).
@end table
@item x264opts (N.A.)
Set any x264 option, see @command{x264 --fullhelp} for a list.
Argument is a list of @var{key}=@var{value} couples separated by
":". In @var{filter} and @var{psy-rd} options that use ":" as a separator ":". 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 themselves, use "," instead. They accept it as well since long ago but this
is kept undocumented for some reason. is kept undocumented for some reason.
@@ -1054,18 +1299,136 @@ For example to specify libx264 encoding options with @command{ffmpeg}:
ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv
@end example @end example
For more information about libx264 and the supported options see: @item x264-params (N.A.)
@url{http://www.videolan.org/developers/x264.html} Override the x264 configuration using a :-separated list of key=value
parameters.
@item -x264-params @var{string} This option is functionally the same as the @option{x264opts}, but is
Override the x264 configuration using a :-separated list of key=value parameters. duplicated for compability with the Libav fork.
For example to specify libx264 encoding options with @command{ffmpeg}:
@example @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 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
@end example @end example
@end table @end table
Encoding avpresets for common usages are provided so they can be used with the Encoding ffpresets for common usages are provided so they can be used with the
general presets system (e.g. passing the @code{-pre} option). general presets system (e.g. passing the @option{pre} option).
@section libxvid
Xvid MPEG-4 Part 2 encoder wrapper.
This encoder requires the presence of the libxvidcore headers and library
during configuration. You need to explicitly configure the build with
@code{--enable-libxvid --enable-gpl}.
The native @code{mpeg4} encoder supports the MPEG-4 Part 2 format, so
users can encode to this format without this library.
@subsection Options
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 @ref{codec-options,,the Codec
Options chapter} for their documentation. The other shared options
which are not listed have no effect for the libxvid encoder.
@table @option
@item b
@item g
@item qmin
@item qmax
@item mpeg_quant
@item threads
@item bf
@item b_qfactor
@item b_qoffset
@item flags
Set specific encoding flags. Possible values:
@table @samp
@item mv4
Use four motion vector by macroblock.
@item aic
Enable high quality AC prediction.
@item gray
Only encode grayscale.
@item gmc
Enable the use of global motion compensation (GMC).
@item qpel
Enable quarter-pixel motion compensation.
@item cgop
Enable closed GOP.
@item global_header
Place global headers in extradata instead of every keyframe.
@end table
@item trellis
@item me_method
Set motion estimation method. Possible values in decreasing order of
speed and increasing order of quality:
@table @samp
@item zero
Use no motion estimation (default).
@item phods
@item x1
@item log
Enable advanced diamond zonal search for 16x16 blocks and half-pixel
refinement for 16x16 blocks. @samp{x1} and @samp{log} are aliases for
@samp{phods}.
@item epzs
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.
@item full
Enable all of the things described above, plus extended 16x16 and 8x8
blocks search.
@end table
@item mbd
Set macroblock decision algorithm. Possible values in the increasing
order of quality:
@table @samp
@item simple
Use macroblock comparing function algorithm (default).
@item bits
Enable rate distortion-based half pixel and quarter pixel refinement for
16x16 blocks.
@item rd
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.
@end table
@end table
@section png @section png

9
doc/formats.texi
View File

@@ -57,6 +57,9 @@ Enable RTP MP4A-LATM payload.
Reduce the latency introduced by optional buffering Reduce the latency introduced by optional buffering
@end table @end table
@item seek2any @var{integer} (@emph{input})
Forces seeking to enable seek to any mode if set to 1. Default is 0.
@item analyzeduration @var{integer} (@emph{input}) @item analyzeduration @var{integer} (@emph{input})
Specify how many microseconds are analyzed to probe the input. A Specify how many microseconds are analyzed to probe the input. A
higher value will allow to detect more accurate information, but will higher value will allow to detect more accurate information, but will
@@ -133,6 +136,12 @@ been without shifting.
Also note that this affects only leading negative timestamps, and not Also note that this affects only leading negative timestamps, and not
non-monotonic negative timestamps. non-monotonic negative timestamps.
@item skip_initial_bytes @var{integer} (@emph{input})
Set number initial bytes to skip. Default is 0.
@item correct_ts_overflow @var{integer} (@emph{input})
Correct single timestamp overflows if set to 1. Default is 1.
@item flush_packets @var{integer} (@emph{output}) @item flush_packets @var{integer} (@emph{output})
Flush the underlying I/O stream after each packet. Default 1 enables it, and Flush the underlying I/O stream after each packet. Default 1 enables it, and
has the effect of reducing the latency; 0 disables it and may slightly has the effect of reducing the latency; 0 disables it and may slightly