The option @code{-codecs} of the ff* tools will display the list of
enabled encoders.
-A description of some of the currently available encoders follows.
+@c man end ENCODERS
+
+@chapter Audio Encoders
+@c man begin AUDIO ENCODERS
-@section Audio Encoders
+A description of some of the currently available audio encoders
+follows.
-@subsection ac3 and ac3_fixed
+@section ac3 and ac3_fixed
AC-3 audio encoders.
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.
-@subheading AC-3 Metadata
+@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
@item @uref{http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/46_DDEncodingGuidelines.pdf,Dolby Digital Professional Encoding Guidelines}
@end itemize
-@subsubheading Metadata Control Options
+@subsubsection Metadata Control Options
@table @option
@end table
-@subsubheading Downmix Levels
+@subsubsection Downmix Levels
@table @option
@end table
-@subsubheading Audio Production Information
+@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.
@end table
-@subsubheading Other Metadata Options
+@subsubsection Other Metadata Options
@table @option
@end table
-@subsubheading Extended Bitstream Information
+@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
and @code{surround_mixlev} options if it supports the Alternate Bit Stream
Syntax.
-@subsubheading Extended Bitstream Information - Part 1
+@subsubsection Extended Bitstream Information - Part 1
@table @option
@end table
-@subsubheading Extended Bitstream Information - Part 2
+@subsubsection Extended Bitstream Information - Part 2
@table @option
@end table
-@subheading Other AC-3 Encoding Options
+@subsection Other AC-3 Encoding Options
@table @option
@end table
-@c man end ENCODERS
+@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 libx264
+
+H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 format supported through
+libx264.
+
+Requires the presence of the libx64 headers and library during
+configuration. You need to explicitely configure the build with
+@code{--enable-libx264}.
+
+@subsection Options
+
+@table @option
+
+@item preset @var{preset_name}
+Set the encoding preset.
+
+@item tune @var{tune_name}
+Tune the encoding params.
+Deprecated in favor of @var{x264_opts}
+
+@item fastfirstpass @var{bool}
+Use fast settings when encoding first pass, default value is 1.
+Deprecated in favor of @var{x264_opts}.
+
+@item profile @var{profile_name}
+Set profile restrictions.
+Deprecated in favor of @var{x264_opts}.
+
+@item level @var{level}
+Specify level (as defined by Annex A).
+Deprecated in favor of @var{x264_opts}.
+
+@item passlogfile @var{filename}
+Specify filename for 2 pass stats.
+Deprecated in favor of @var{x264_opts}.
+
+@item wpredp @var{wpred_type}
+Specify Weighted prediction for P-frames.
+Deprecated in favor of @var{x264_opts}.
+
+@item x264opts @var{options}
+Allow to set any x264 option, see x264 manual for a list.
+
+@var{options} is a list of @var{key}=@var{value} couples separated by
+":".
+@end table
+
+For example to specify libx264 encoding options with @file{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}
+
+@c man end VIDEO ENCODERS
projects / ffmpeg / blobdiff