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
+The option @code{-encoders} of the ff* tools will display the list of
enabled encoders.
@c man end ENCODERS
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.
+described below, but somewhat a little better and slower.
@item anmr
Average noise to mask ratio (ANMR) trellis-based solution.
+qscale} options, is experimental and only works with some
combinations of parameters.
+Support for encoding 7.1 audio is only available with libfdk-aac 0.1.3 or
+higher.
+
For more information see the fdk-aac project at
@url{http://sourceforge.net/p/opencore-amr/fdk-aac/}.
@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
+has this enabled by default, but can be overridden by use
@option{--nores} option.
@item joint_stereo (@emph{-m j})
@subsection Option Mapping
-Most libopus options are modeled after the @command{opusenc} utility from
+Most libopus options are modelled after the @command{opusenc} utility from
opus-tools. The following is an option mapping chart describing options
supported by the libopus wrapper, and their @command{opusenc}-equivalent
in parentheses.
@end table
+@anchor{libwavpack}
@section libwavpack
A wrapper providing WavPack encoding through libwavpack.
Only lossless mode using 32-bit integer samples is supported currently.
-The @option{compression_level} option can be used to control speed vs.
-compression tradeoff, with the values mapped to libwavpack as follows:
+
+Requires the presence of the libwavpack headers and library during
+configuration. You need to explicitly configure the build with
+@code{--enable-libwavpack}.
+
+Note that a libavcodec-native encoder for the WavPack codec exists so users can
+encode audios with this codec without using this encoder. See @ref{wavpackenc}.
+
+@subsection Options
+
+@command{wavpack} command line utility's corresponding options are listed in
+parentheses, if any.
@table @option
+@item frame_size (@emph{--blocksize})
+Default is 32768.
-@item 0
-Fast mode - corresponding to the wavpack @option{-f} option.
+@item compression_level
+Set speed vs. compression tradeoff. Acceptable arguments are listed below:
+
+@table @samp
+@item 0 (@emph{-f})
+Fast mode.
@item 1
Normal (default) settings.
-@item 2
-High quality - corresponding to the wavpack @option{-h} option.
+@item 2 (@emph{-h})
+High quality.
-@item 3
-Very high quality - corresponding to the wavpack @option{-hh} option.
+@item 3 (@emph{-hh})
+Very high quality.
-@item 4-8
-Same as 3, but with extra processing enabled - corresponding to the wavpack
-@option{-x} option. I.e. 4 is the same as @option{-x2} and 8 is the same as
-@option{-x6}.
+@item 4-8 (@emph{-hh -x}@var{EXTRAPROC})
+Same as @samp{3}, but with extra processing enabled.
+
+@samp{4} is the same as @option{-x2} and @samp{8} is the same as @option{-x6}.
+
+@end table
+@end table
+
+@anchor{wavpackenc}
+@section wavpack
+
+WavPack lossless audio encoder.
+
+This is a libavcodec-native WavPack encoder. There is also an encoder based on
+libwavpack, but there is virtually no reason to use that encoder.
+
+See also @ref{libwavpack}.
+
+@subsection Options
+
+The equivalent options for @command{wavpack} command line utility are listed in
+parentheses.
+
+@subsubsection Shared options
+
+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 @ref{codec-options,,the Codec Options chapter}.
+
+@table @option
+@item frame_size (@emph{--blocksize})
+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.
+
+For the complete formula of calculating default, see
+@file{libavcodec/wavpackenc.c}.
+
+@item compression_level (@emph{-f}, @emph{-h}, @emph{-hh}, and @emph{-x})
+This option's syntax is consistent with @ref{libwavpack}'s.
+@end table
+
+@subsubsection Private options
+
+@table @option
+@item joint_stereo (@emph{-j})
+Set whether to enable joint stereo. Valid values are:
+
+@table @samp
+@item on (@emph{1})
+Force mid/side audio encoding.
+@item off (@emph{0})
+Force left/right audio encoding.
+@item auto
+Let the encoder decide automatically.
+@end table
+
+@item optimize_mono
+Set whether to enable optimization for mono. This option is only effective for
+non-mono streams. Available values:
+
+@table @samp
+@item on
+enabled
+@item off
+disabled
+@end table
@end table
configuration. You need to explicitly configure the build with
@code{--enable-libtheora}.
-For more informations about the libtheora project see
+For more information about the libtheora project see
@url{http://www.theora.org/}.
@subsection Options
For more information about libvpx see:
@url{http://www.webmproject.org/}
-@section libx264
+
+@section libwebp
+
+libwebp WebP Image encoder wrapper
+
+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.
+
+@subsection Pixel Format
+
+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.
+
+@subsection Options
+
+@table @option
+
+@item -lossless @var{boolean}
+Enables/Disables use of lossless mode. Default is 0.
+
+@item -compression_level @var{integer}
+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{method} option in libwebp. The valid range is 0 to 6.
+Default is 4.
+
+@item -qscale @var{float}
+For lossy encoding, this controls image quality, 0 to 100. For lossless
+encoding, this controls the effort and time spent at compressing more. The
+default value is 75. Note that for usage via libavcodec, this option is called
+@var{global_quality} and must be multiplied by @var{FF_QP2LAMBDA}.
+
+@item -preset @var{type}
+Configuration preset. This does some automatic settings based on the general
+type of the image.
+@table @option
+@item none
+Do not use a preset.
+@item default
+Use the encoder default.
+@item picture
+Digital picture, like portrait, inner shot
+@item photo
+Outdoor photograph, with natural lighting
+@item drawing
+Hand or line drawing, with high-contrast details
+@item icon
+Small-sized colorful images
+@item text
+Text-like
+@end table
+
+@end table
+
+@section libx264, libx264rgb
x264 H.264/MPEG-4 AVC encoder wrapper.
Many libx264 encoder options are mapped to FFmpeg global codec
options, while unique encoder options are provided through private
options. Additionally the @option{x264opts} and @option{x264-params}
-private options allows to pass a list of key=value tuples as accepted
+private options allows one to pass a list of key=value tuples as accepted
by the libx264 @code{x264_param_parse} function.
The x264 project website is at
@url{http://www.videolan.org/developers/x264.html}.
+The libx264rgb encoder is the same as libx264, except it accepts packed RGB
+pixel formats as input instead of YUV.
+
+@subsection Supported Pixel Formats
+
+x264 supports 8- to 10-bit color spaces. The exact bit depth is controlled at
+x264's configure time. FFmpeg only supports one bit depth in one particular
+build. In other words, it is not possible to build one FFmpeg with multiple
+versions of x264 with different bit depths.
+
@subsection Options
The following options are supported by the libx264 wrapper. The
@item g (@emph{keyint})
-@item qmax (@emph{qpmax})
-
@item qmin (@emph{qpmin})
+Minimum quantizer scale.
+
+@item qmax (@emph{qpmax})
+Maximum quantizer scale.
@item qdiff (@emph{qpstep})
+Maximum difference between quantizer scales.
@item qblur (@emph{qblur})
+Quantizer curve blur
@item qcomp (@emph{qcomp})
+Quantizer curve compression factor
@item refs (@emph{ref})
+Number of reference frames each P-frame can use. The range is from @var{0-16}.
@item sc_threshold (@emph{scenecut})
+Sets the threshold for the scene change detection.
@item trellis (@emph{trellis})
+Performs Trellis quantization to increase efficiency. Enabled by default.
@item nr (@emph{nr})
@item me_range (@emph{merange})
+Maximum range of the motion search in pixels.
@item me_method (@emph{me})
Set motion estimation method. Possible values in the decreasing order
@end table
@item subq (@emph{subme})
+Sub-pixel motion estimation method.
@item b_strategy (@emph{b-adapt})
+Adaptive B-frame placement decision algorithm. Use only on first-pass.
@item keyint_min (@emph{min-keyint})
+Minimum GOP size.
@item coder
Set entropy encoder. Possible values:
@end table
@item threads (@emph{threads})
+Number of encoding threads.
@item thread_type
Set multithreading technique. Possible values:
parameters.
This option is functionally the same as the @option{x264opts}, but is
-duplicated for compability with the Libav fork.
+duplicated for compatibility with the Libav fork.
For example to specify libx264 encoding options with @command{ffmpeg}:
@example
@end table
+@section mpeg2
+
+MPEG-2 video encoder.
+
+@subsection Options
+
+@table @option
+@item seq_disp_ext @var{integer}
+Specifies if the encoder should write a sequence_display_extension to the
+output.
+@table @option
+@item -1
+@itemx auto
+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.
+@item 0
+@itemx never
+Never write it.
+@item 1
+@itemx always
+Always write it.
+@end table
+@end table
+
@section png
PNG image encoder.
Apple ProRes encoder.
FFmpeg contains 2 ProRes encoders, the prores-aw and prores-ks encoder.
-The used encoder can be choosen with the @code{-vcodec} option.
+The used encoder can be chosen with the @code{-vcodec} option.
@subsection Private Options for prores-ks
recommended value) and do not set a size constraint.
@c man end VIDEO ENCODERS
+
+@chapter Subtitles Encoders
+@c man begin SUBTITLES ENCODERS
+
+@section dvdsub
+
+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.
+
+@subsection Options
+
+@table @option
+@item even_rows_fix
+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.
+
+By default, this work-around is disabled.
+@end table
+
+@c man end SUBTITLES ENCODERS
projects / platform / framework / web / crosswalk.git / blobdiff