yading@10: @chapter Encoders
yading@10: @c man begin ENCODERS
yading@10: 
yading@10: Encoders are configured elements in FFmpeg which allow the encoding of
yading@10: multimedia streams.
yading@10: 
yading@10: When you configure your FFmpeg build, all the supported native encoders
yading@10: are enabled by default. Encoders requiring an external library must be enabled
yading@10: manually via the corresponding @code{--enable-lib} option. You can list all
yading@10: available encoders using the configure option @code{--list-encoders}.
yading@10: 
yading@10: You can disable all the encoders with the configure option
yading@10: @code{--disable-encoders} and selectively enable / disable single encoders
yading@10: with the options @code{--enable-encoder=@var{ENCODER}} /
yading@10: @code{--disable-encoder=@var{ENCODER}}.
yading@10: 
yading@10: The option @code{-codecs} of the ff* tools will display the list of
yading@10: enabled encoders.
yading@10: 
yading@10: @c man end ENCODERS
yading@10: 
yading@10: @chapter Audio Encoders
yading@10: @c man begin AUDIO ENCODERS
yading@10: 
yading@10: A description of some of the currently available audio encoders
yading@10: follows.
yading@10: 
yading@10: @section ac3 and ac3_fixed
yading@10: 
yading@10: AC-3 audio encoders.
yading@10: 
yading@10: These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366, as well as
yading@10: the undocumented RealAudio 3 (a.k.a. dnet).
yading@10: 
yading@10: The @var{ac3} encoder uses floating-point math, while the @var{ac3_fixed}
yading@10: encoder only uses fixed-point integer math. This does not mean that one is
yading@10: always faster, just that one or the other may be better suited to a
yading@10: particular system. The floating-point encoder will generally produce better
yading@10: quality audio for a given bitrate. The @var{ac3_fixed} encoder is not the
yading@10: default codec for any of the output formats, so it must be specified explicitly
yading@10: using the option @code{-acodec ac3_fixed} in order to use it.
yading@10: 
yading@10: @subsection AC-3 Metadata
yading@10: 
yading@10: The AC-3 metadata options are used to set parameters that describe the audio,
yading@10: but in most cases do not affect the audio encoding itself. Some of the options
yading@10: do directly affect or influence the decoding and playback of the resulting
yading@10: bitstream, while others are just for informational purposes. A few of the
yading@10: options will add bits to the output stream that could otherwise be used for
yading@10: audio data, and will thus affect the quality of the output. Those will be
yading@10: indicated accordingly with a note in the option list below.
yading@10: 
yading@10: These parameters are described in detail in several publicly-available
yading@10: documents.
yading@10: @itemize
yading@10: @item @uref{http://www.atsc.org/cms/standards/a_52-2010.pdf,A/52:2010 - Digital Audio Compression (AC-3) (E-AC-3) Standard}
yading@10: @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}
yading@10: @item @uref{http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/18_Metadata.Guide.pdf,Dolby Metadata Guide}
yading@10: @item @uref{http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/46_DDEncodingGuidelines.pdf,Dolby Digital Professional Encoding Guidelines}
yading@10: @end itemize
yading@10: 
yading@10: @subsubsection Metadata Control Options
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -per_frame_metadata @var{boolean}
yading@10: Allow Per-Frame Metadata. Specifies if the encoder should check for changing
yading@10: metadata for each frame.
yading@10: @table @option
yading@10: @item 0
yading@10: The metadata values set at initialization will be used for every frame in the
yading@10: stream. (default)
yading@10: @item 1
yading@10: Metadata values can be changed before encoding each frame.
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsubsection Downmix Levels
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -center_mixlev @var{level}
yading@10: Center Mix Level. The amount of gain the decoder should apply to the center
yading@10: channel when downmixing to stereo. This field will only be written to the
yading@10: bitstream if a center channel is present. The value is specified as a scale
yading@10: factor. There are 3 valid values:
yading@10: @table @option
yading@10: @item 0.707
yading@10: Apply -3dB gain
yading@10: @item 0.595
yading@10: Apply -4.5dB gain (default)
yading@10: @item 0.500
yading@10: Apply -6dB gain
yading@10: @end table
yading@10: 
yading@10: @item -surround_mixlev @var{level}
yading@10: Surround Mix Level. The amount of gain the decoder should apply to the surround
yading@10: channel(s) when downmixing to stereo. This field will only be written to the
yading@10: bitstream if one or more surround channels are present. The value is specified
yading@10: as a scale factor.  There are 3 valid values:
yading@10: @table @option
yading@10: @item 0.707
yading@10: Apply -3dB gain
yading@10: @item 0.500
yading@10: Apply -6dB gain (default)
yading@10: @item 0.000
yading@10: Silence Surround Channel(s)
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsubsection Audio Production Information
yading@10: Audio Production Information is optional information describing the mixing
yading@10: environment.  Either none or both of the fields are written to the bitstream.
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -mixing_level @var{number}
yading@10: Mixing Level. Specifies peak sound pressure level (SPL) in the production
yading@10: environment when the mix was mastered. Valid values are 80 to 111, or -1 for
yading@10: unknown or not indicated. The default value is -1, but that value cannot be
yading@10: used if the Audio Production Information is written to the bitstream. Therefore,
yading@10: if the @code{room_type} option is not the default value, the @code{mixing_level}
yading@10: option must not be -1.
yading@10: 
yading@10: @item -room_type @var{type}
yading@10: Room Type. Describes the equalization used during the final mixing session at
yading@10: the studio or on the dubbing stage. A large room is a dubbing stage with the
yading@10: industry standard X-curve equalization; a small room has flat equalization.
yading@10: This field will not be written to the bitstream if both the @code{mixing_level}
yading@10: option and the @code{room_type} option have the default values.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx notindicated
yading@10: Not Indicated (default)
yading@10: @item 1
yading@10: @itemx large
yading@10: Large Room
yading@10: @item 2
yading@10: @itemx small
yading@10: Small Room
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsubsection Other Metadata Options
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -copyright @var{boolean}
yading@10: Copyright Indicator. Specifies whether a copyright exists for this audio.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx off
yading@10: No Copyright Exists (default)
yading@10: @item 1
yading@10: @itemx on
yading@10: Copyright Exists
yading@10: @end table
yading@10: 
yading@10: @item -dialnorm @var{value}
yading@10: Dialogue Normalization. Indicates how far the average dialogue level of the
yading@10: program is below digital 100% full scale (0 dBFS). This parameter determines a
yading@10: level shift during audio reproduction that sets the average volume of the
yading@10: dialogue to a preset level. The goal is to match volume level between program
yading@10: sources. A value of -31dB will result in no volume level change, relative to
yading@10: the source volume, during audio reproduction. Valid values are whole numbers in
yading@10: the range -31 to -1, with -31 being the default.
yading@10: 
yading@10: @item -dsur_mode @var{mode}
yading@10: Dolby Surround Mode. Specifies whether the stereo signal uses Dolby Surround
yading@10: (Pro Logic). This field will only be written to the bitstream if the audio
yading@10: stream is stereo. Using this option does @b{NOT} mean the encoder will actually
yading@10: apply Dolby Surround processing.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx notindicated
yading@10: Not Indicated (default)
yading@10: @item 1
yading@10: @itemx off
yading@10: Not Dolby Surround Encoded
yading@10: @item 2
yading@10: @itemx on
yading@10: Dolby Surround Encoded
yading@10: @end table
yading@10: 
yading@10: @item -original @var{boolean}
yading@10: Original Bit Stream Indicator. Specifies whether this audio is from the
yading@10: original source and not a copy.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx off
yading@10: Not Original Source
yading@10: @item 1
yading@10: @itemx on
yading@10: Original Source (default)
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsection Extended Bitstream Information
yading@10: The extended bitstream options are part of the Alternate Bit Stream Syntax as
yading@10: specified in Annex D of the A/52:2010 standard. It is grouped into 2 parts.
yading@10: If any one parameter in a group is specified, all values in that group will be
yading@10: written to the bitstream.  Default values are used for those that are written
yading@10: but have not been specified.  If the mixing levels are written, the decoder
yading@10: will use these values instead of the ones specified in the @code{center_mixlev}
yading@10: and @code{surround_mixlev} options if it supports the Alternate Bit Stream
yading@10: Syntax.
yading@10: 
yading@10: @subsubsection Extended Bitstream Information - Part 1
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -dmix_mode @var{mode}
yading@10: Preferred Stereo Downmix Mode. Allows the user to select either Lt/Rt
yading@10: (Dolby Surround) or Lo/Ro (normal stereo) as the preferred stereo downmix mode.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx notindicated
yading@10: Not Indicated (default)
yading@10: @item 1
yading@10: @itemx ltrt
yading@10: Lt/Rt Downmix Preferred
yading@10: @item 2
yading@10: @itemx loro
yading@10: Lo/Ro Downmix Preferred
yading@10: @end table
yading@10: 
yading@10: @item -ltrt_cmixlev @var{level}
yading@10: Lt/Rt Center Mix Level. The amount of gain the decoder should apply to the
yading@10: center channel when downmixing to stereo in Lt/Rt mode.
yading@10: @table @option
yading@10: @item 1.414
yading@10: Apply +3dB gain
yading@10: @item 1.189
yading@10: Apply +1.5dB gain
yading@10: @item 1.000
yading@10: Apply 0dB gain
yading@10: @item 0.841
yading@10: Apply -1.5dB gain
yading@10: @item 0.707
yading@10: Apply -3.0dB gain
yading@10: @item 0.595
yading@10: Apply -4.5dB gain (default)
yading@10: @item 0.500
yading@10: Apply -6.0dB gain
yading@10: @item 0.000
yading@10: Silence Center Channel
yading@10: @end table
yading@10: 
yading@10: @item -ltrt_surmixlev @var{level}
yading@10: Lt/Rt Surround Mix Level. The amount of gain the decoder should apply to the
yading@10: surround channel(s) when downmixing to stereo in Lt/Rt mode.
yading@10: @table @option
yading@10: @item 0.841
yading@10: Apply -1.5dB gain
yading@10: @item 0.707
yading@10: Apply -3.0dB gain
yading@10: @item 0.595
yading@10: Apply -4.5dB gain
yading@10: @item 0.500
yading@10: Apply -6.0dB gain (default)
yading@10: @item 0.000
yading@10: Silence Surround Channel(s)
yading@10: @end table
yading@10: 
yading@10: @item -loro_cmixlev @var{level}
yading@10: Lo/Ro Center Mix Level. The amount of gain the decoder should apply to the
yading@10: center channel when downmixing to stereo in Lo/Ro mode.
yading@10: @table @option
yading@10: @item 1.414
yading@10: Apply +3dB gain
yading@10: @item 1.189
yading@10: Apply +1.5dB gain
yading@10: @item 1.000
yading@10: Apply 0dB gain
yading@10: @item 0.841
yading@10: Apply -1.5dB gain
yading@10: @item 0.707
yading@10: Apply -3.0dB gain
yading@10: @item 0.595
yading@10: Apply -4.5dB gain (default)
yading@10: @item 0.500
yading@10: Apply -6.0dB gain
yading@10: @item 0.000
yading@10: Silence Center Channel
yading@10: @end table
yading@10: 
yading@10: @item -loro_surmixlev @var{level}
yading@10: Lo/Ro Surround Mix Level. The amount of gain the decoder should apply to the
yading@10: surround channel(s) when downmixing to stereo in Lo/Ro mode.
yading@10: @table @option
yading@10: @item 0.841
yading@10: Apply -1.5dB gain
yading@10: @item 0.707
yading@10: Apply -3.0dB gain
yading@10: @item 0.595
yading@10: Apply -4.5dB gain
yading@10: @item 0.500
yading@10: Apply -6.0dB gain (default)
yading@10: @item 0.000
yading@10: Silence Surround Channel(s)
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsubsection Extended Bitstream Information - Part 2
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -dsurex_mode @var{mode}
yading@10: Dolby Surround EX Mode. Indicates whether the stream uses Dolby Surround EX
yading@10: (7.1 matrixed to 5.1). Using this option does @b{NOT} mean the encoder will actually
yading@10: apply Dolby Surround EX processing.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx notindicated
yading@10: Not Indicated (default)
yading@10: @item 1
yading@10: @itemx on
yading@10: Dolby Surround EX Off
yading@10: @item 2
yading@10: @itemx off
yading@10: Dolby Surround EX On
yading@10: @end table
yading@10: 
yading@10: @item -dheadphone_mode @var{mode}
yading@10: Dolby Headphone Mode. Indicates whether the stream uses Dolby Headphone
yading@10: encoding (multi-channel matrixed to 2.0 for use with headphones). Using this
yading@10: option does @b{NOT} mean the encoder will actually apply Dolby Headphone
yading@10: processing.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx notindicated
yading@10: Not Indicated (default)
yading@10: @item 1
yading@10: @itemx on
yading@10: Dolby Headphone Off
yading@10: @item 2
yading@10: @itemx off
yading@10: Dolby Headphone On
yading@10: @end table
yading@10: 
yading@10: @item -ad_conv_type @var{type}
yading@10: A/D Converter Type. Indicates whether the audio has passed through HDCD A/D
yading@10: conversion.
yading@10: @table @option
yading@10: @item 0
yading@10: @itemx standard
yading@10: Standard A/D Converter (default)
yading@10: @item 1
yading@10: @itemx hdcd
yading@10: HDCD A/D Converter
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsection Other AC-3 Encoding Options
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -stereo_rematrixing @var{boolean}
yading@10: Stereo Rematrixing. Enables/Disables use of rematrixing for stereo input. This
yading@10: is an optional AC-3 feature that increases quality by selectively encoding
yading@10: the left/right channels as mid/side. This option is enabled by default, and it
yading@10: is highly recommended that it be left as enabled except for testing purposes.
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsection Floating-Point-Only AC-3 Encoding Options
yading@10: 
yading@10: These options are only valid for the floating-point encoder and do not exist
yading@10: for the fixed-point encoder due to the corresponding features not being
yading@10: implemented in fixed-point.
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item -channel_coupling @var{boolean}
yading@10: Enables/Disables use of channel coupling, which is an optional AC-3 feature
yading@10: that increases quality by combining high frequency information from multiple
yading@10: channels into a single channel. The per-channel high frequency information is
yading@10: sent with less accuracy in both the frequency and time domains. This allows
yading@10: more bits to be used for lower frequencies while preserving enough information
yading@10: to reconstruct the high frequencies. This option is enabled by default for the
yading@10: floating-point encoder and should generally be left as enabled except for
yading@10: testing purposes or to increase encoding speed.
yading@10: @table @option
yading@10: @item -1
yading@10: @itemx auto
yading@10: Selected by Encoder (default)
yading@10: @item 0
yading@10: @itemx off
yading@10: Disable Channel Coupling
yading@10: @item 1
yading@10: @itemx on
yading@10: Enable Channel Coupling
yading@10: @end table
yading@10: 
yading@10: @item -cpl_start_band @var{number}
yading@10: Coupling Start Band. Sets the channel coupling start band, from 1 to 15. If a
yading@10: value higher than the bandwidth is used, it will be reduced to 1 less than the
yading@10: coupling end band. If @var{auto} is used, the start band will be determined by
yading@10: the encoder based on the bit rate, sample rate, and channel layout. This option
yading@10: has no effect if channel coupling is disabled.
yading@10: @table @option
yading@10: @item -1
yading@10: @itemx auto
yading@10: Selected by Encoder (default)
yading@10: @end table
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @c man end AUDIO ENCODERS
yading@10: 
yading@10: @chapter Video Encoders
yading@10: @c man begin VIDEO ENCODERS
yading@10: 
yading@10: A description of some of the currently available video encoders
yading@10: follows.
yading@10: 
yading@10: @section libtheora
yading@10: 
yading@10: Theora format supported through libtheora.
yading@10: 
yading@10: Requires the presence of the libtheora headers and library during
yading@10: configuration. You need to explicitly configure the build with
yading@10: @code{--enable-libtheora}.
yading@10: 
yading@10: @subsection Options
yading@10: 
yading@10: The following global options are mapped to internal libtheora options
yading@10: which affect the quality and the bitrate of the encoded stream.
yading@10: 
yading@10: @table @option
yading@10: @item b
yading@10: Set the video bitrate, only works if the @code{qscale} flag in
yading@10: @option{flags} is not enabled.
yading@10: 
yading@10: @item flags
yading@10: Used to enable constant quality mode encoding through the
yading@10: @option{qscale} flag, and to enable the @code{pass1} and @code{pass2}
yading@10: modes.
yading@10: 
yading@10: @item g
yading@10: Set the GOP size.
yading@10: 
yading@10: @item global_quality
yading@10: Set the global quality in lambda units, only works if the
yading@10: @code{qscale} flag in @option{flags} is enabled. The value is clipped
yading@10: in the [0 - 10*@code{FF_QP2LAMBDA}] range, and then multiplied for 6.3
yading@10: to get a value in the native libtheora range [0-63]. A higher value
yading@10: corresponds to a higher quality.
yading@10: 
yading@10: For example, to set maximum constant quality encoding with
yading@10: @command{ffmpeg}:
yading@10: @example
yading@10: ffmpeg -i INPUT -flags:v qscale -global_quality:v "10*QP2LAMBDA" -codec:v libtheora OUTPUT.ogg
yading@10: @end example
yading@10: @end table
yading@10: 
yading@10: @section libvpx
yading@10: 
yading@10: VP8 format supported through libvpx.
yading@10: 
yading@10: Requires the presence of the libvpx headers and library during configuration.
yading@10: You need to explicitly configure the build with @code{--enable-libvpx}.
yading@10: 
yading@10: @subsection Options
yading@10: 
yading@10: Mapping from FFmpeg to libvpx options with conversion notes in parentheses.
yading@10: 
yading@10: @table @option
yading@10: 
yading@10: @item threads
yading@10: g_threads
yading@10: 
yading@10: @item profile
yading@10: g_profile
yading@10: 
yading@10: @item vb
yading@10: rc_target_bitrate
yading@10: 
yading@10: @item g
yading@10: kf_max_dist
yading@10: 
yading@10: @item keyint_min
yading@10: kf_min_dist
yading@10: 
yading@10: @item qmin
yading@10: rc_min_quantizer
yading@10: 
yading@10: @item qmax
yading@10: rc_max_quantizer
yading@10: 
yading@10: @item bufsize, vb
yading@10: rc_buf_sz
yading@10: @code{(bufsize * 1000 / vb)}
yading@10: 
yading@10: rc_buf_optimal_sz
yading@10: @code{(bufsize * 1000 / vb * 5 / 6)}
yading@10: 
yading@10: @item rc_init_occupancy, vb
yading@10: rc_buf_initial_sz
yading@10: @code{(rc_init_occupancy * 1000 / vb)}
yading@10: 
yading@10: @item rc_buffer_aggressivity
yading@10: rc_undershoot_pct
yading@10: 
yading@10: @item skip_threshold
yading@10: rc_dropframe_thresh
yading@10: 
yading@10: @item qcomp
yading@10: rc_2pass_vbr_bias_pct
yading@10: 
yading@10: @item maxrate, vb
yading@10: rc_2pass_vbr_maxsection_pct
yading@10: @code{(maxrate * 100 / vb)}
yading@10: 
yading@10: @item minrate, vb
yading@10: rc_2pass_vbr_minsection_pct
yading@10: @code{(minrate * 100 / vb)}
yading@10: 
yading@10: @item minrate, maxrate, vb
yading@10: @code{VPX_CBR}
yading@10: @code{(minrate == maxrate == vb)}
yading@10: 
yading@10: @item crf
yading@10: @code{VPX_CQ}, @code{VP8E_SET_CQ_LEVEL}
yading@10: 
yading@10: @item quality
yading@10: @table @option
yading@10: @item @var{best}
yading@10: @code{VPX_DL_BEST_QUALITY}
yading@10: @item @var{good}
yading@10: @code{VPX_DL_GOOD_QUALITY}
yading@10: @item @var{realtime}
yading@10: @code{VPX_DL_REALTIME}
yading@10: @end table
yading@10: 
yading@10: @item speed
yading@10: @code{VP8E_SET_CPUUSED}
yading@10: 
yading@10: @item nr
yading@10: @code{VP8E_SET_NOISE_SENSITIVITY}
yading@10: 
yading@10: @item mb_threshold
yading@10: @code{VP8E_SET_STATIC_THRESHOLD}
yading@10: 
yading@10: @item slices
yading@10: @code{VP8E_SET_TOKEN_PARTITIONS}
yading@10: 
yading@10: @item max-intra-rate
yading@10: @code{VP8E_SET_MAX_INTRA_BITRATE_PCT}
yading@10: 
yading@10: @item force_key_frames
yading@10: @code{VPX_EFLAG_FORCE_KF}
yading@10: 
yading@10: @item Alternate reference frame related
yading@10: @table @option
yading@10: @item vp8flags altref
yading@10: @code{VP8E_SET_ENABLEAUTOALTREF}
yading@10: @item @var{arnr_max_frames}
yading@10: @code{VP8E_SET_ARNR_MAXFRAMES}
yading@10: @item @var{arnr_type}
yading@10: @code{VP8E_SET_ARNR_TYPE}
yading@10: @item @var{arnr_strength}
yading@10: @code{VP8E_SET_ARNR_STRENGTH}
yading@10: @item @var{rc_lookahead}
yading@10: g_lag_in_frames
yading@10: @end table
yading@10: 
yading@10: @item vp8flags error_resilient
yading@10: g_error_resilient
yading@10: 
yading@10: @end table
yading@10: 
yading@10: For more information about libvpx see:
yading@10: @url{http://www.webmproject.org/}
yading@10: 
yading@10: @section libx264
yading@10: 
yading@10: x264 H.264/MPEG-4 AVC encoder wrapper
yading@10: 
yading@10: Requires the presence of the libx264 headers and library during
yading@10: configuration. You need to explicitly configure the build with
yading@10: @code{--enable-libx264}.
yading@10: 
yading@10: x264 supports an impressive number of features, including 8x8 and 4x4 adaptive
yading@10: spatial transform, adaptive B-frame placement, CAVLC/CABAC entropy coding,
yading@10: interlacing (MBAFF), lossless mode, psy optimizations for detail retention
yading@10: (adaptive quantization, psy-RD, psy-trellis).
yading@10: 
yading@10: The FFmpeg wrapper provides a mapping for most of them using global options
yading@10: that match those of the encoders and provides private options for the unique
yading@10: encoder options. Additionally an expert override is provided to directly pass
yading@10: a list of key=value tuples as accepted by x264_param_parse.
yading@10: 
yading@10: @subsection Option Mapping
yading@10: 
yading@10: The following options are supported by the x264 wrapper, the x264-equivalent
yading@10: options follow the FFmpeg ones.
yading@10: 
yading@10: @multitable @columnfractions .2 .2
yading@10: @item b                 @tab bitrate
yading@10: FFmpeg @code{b} option is expressed in bits/s, x264 @code{bitrate} in kilobits/s.
yading@10: @item bf                @tab bframes
yading@10: Maximum number of B-frames.
yading@10: @item g                 @tab keyint
yading@10: Maximum GOP size.
yading@10: @item qmin              @tab qpmin
yading@10: @item qmax              @tab qpmax
yading@10: @item qdiff             @tab qpstep
yading@10: @item qblur             @tab qblur
yading@10: @item qcomp             @tab qcomp
yading@10: @item refs              @tab ref
yading@10: @item sc_threshold      @tab scenecut
yading@10: @item trellis           @tab trellis
yading@10: @item nr                @tab nr
yading@10: Noise reduction.
yading@10: @item me_range          @tab merange
yading@10: @item me_method         @tab me
yading@10: @item subq              @tab subme
yading@10: @item b_strategy        @tab b-adapt
yading@10: @item keyint_min        @tab keyint-min
yading@10: @item coder             @tab cabac
yading@10: Set coder to @code{ac} to use CABAC.
yading@10: @item cmp               @tab chroma-me
yading@10: Set to @code{chroma} to use chroma motion estimation.
yading@10: @item threads           @tab threads
yading@10: @item thread_type       @tab sliced_threads
yading@10: Set to @code{slice} to use sliced threading instead of frame threading.
yading@10: @item flags -cgop       @tab open-gop
yading@10: Set @code{-cgop} to use recovery points to close GOPs.
yading@10: @item rc_init_occupancy @tab vbv-init
yading@10: Initial buffer occupancy.
yading@10: @end multitable
yading@10: 
yading@10: @subsection Private Options
yading@10: @table @option
yading@10: @item -preset @var{string}
yading@10: Set the encoding preset (cf. x264 --fullhelp).
yading@10: @item -tune @var{string}
yading@10: Tune the encoding params (cf. x264 --fullhelp).
yading@10: @item -profile @var{string}
yading@10: Set profile restrictions (cf. x264 --fullhelp).
yading@10: @item -fastfirstpass @var{integer}
yading@10: Use fast settings when encoding first pass.
yading@10: @item -crf @var{float}
yading@10: Select the quality for constant quality mode.
yading@10: @item -crf_max @var{float}
yading@10: In CRF mode, prevents VBV from lowering quality beyond this point.
yading@10: @item -qp @var{integer}
yading@10: Constant quantization parameter rate control method.
yading@10: @item -aq-mode @var{integer}
yading@10: AQ method
yading@10: 
yading@10: Possible values:
yading@10: @table @samp
yading@10: @item none
yading@10: 
yading@10: @item variance
yading@10: Variance AQ (complexity mask).
yading@10: @item autovariance
yading@10: Auto-variance AQ (experimental).
yading@10: @end table
yading@10: @item -aq-strength @var{float}
yading@10: AQ strength, reduces blocking and blurring in flat and textured areas.
yading@10: @item -psy @var{integer}
yading@10: Use psychovisual optimizations.
yading@10: @item -psy-rd @var{string}
yading@10: Strength of psychovisual optimization, in <psy-rd>:<psy-trellis> format.
yading@10: @item -rc-lookahead @var{integer}
yading@10: Number of frames to look ahead for frametype and ratecontrol.
yading@10: @item -weightb @var{integer}
yading@10: Weighted prediction for B-frames.
yading@10: @item -weightp @var{integer}
yading@10: Weighted prediction analysis method.
yading@10: 
yading@10: Possible values:
yading@10: @table @samp
yading@10: @item none
yading@10: 
yading@10: @item simple
yading@10: 
yading@10: @item smart
yading@10: 
yading@10: @end table
yading@10: @item -ssim @var{integer}
yading@10: Calculate and print SSIM stats.
yading@10: @item -intra-refresh @var{integer}
yading@10: Use Periodic Intra Refresh instead of IDR frames.
yading@10: @item -b-bias @var{integer}
yading@10: Influences how often B-frames are used.
yading@10: @item -b-pyramid @var{integer}
yading@10: Keep some B-frames as references.
yading@10: 
yading@10: Possible values:
yading@10: @table @samp
yading@10: @item none
yading@10: 
yading@10: @item strict
yading@10: Strictly hierarchical pyramid.
yading@10: @item normal
yading@10: Non-strict (not Blu-ray compatible).
yading@10: @end table
yading@10: @item -mixed-refs @var{integer}
yading@10: One reference per partition, as opposed to one reference per macroblock.
yading@10: @item -8x8dct @var{integer}
yading@10: High profile 8x8 transform.
yading@10: @item -fast-pskip @var{integer}
yading@10: @item -aud @var{integer}
yading@10: Use access unit delimiters.
yading@10: @item -mbtree @var{integer}
yading@10: Use macroblock tree ratecontrol.
yading@10: @item -deblock @var{string}
yading@10: Loop filter parameters, in <alpha:beta> form.
yading@10: @item -cplxblur @var{float}
yading@10: Reduce fluctuations in QP (before curve compression).
yading@10: @item -partitions @var{string}
yading@10: A comma-separated list of partitions to consider, possible values: p8x8, p4x4, b8x8, i8x8, i4x4, none, all.
yading@10: @item -direct-pred @var{integer}
yading@10: Direct MV prediction mode
yading@10: 
yading@10: Possible values:
yading@10: @table @samp
yading@10: @item none
yading@10: 
yading@10: @item spatial
yading@10: 
yading@10: @item temporal
yading@10: 
yading@10: @item auto
yading@10: 
yading@10: @end table
yading@10: @item -slice-max-size @var{integer}
yading@10: Limit the size of each slice in bytes.
yading@10: @item -stats @var{string}
yading@10: Filename for 2 pass stats.
yading@10: @item -nal-hrd @var{integer}
yading@10: Signal HRD information (requires vbv-bufsize; cbr not allowed in .mp4).
yading@10: 
yading@10: Possible values:
yading@10: @table @samp
yading@10: @item none
yading@10: 
yading@10: @item vbr
yading@10: 
yading@10: @item cbr
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @item x264opts @var{options}
yading@10: Allow to set any x264 option, see @code{x264 --fullhelp} for a list.
yading@10: 
yading@10: @var{options} is a list of @var{key}=@var{value} couples separated by
yading@10: ":". In @var{filter} and @var{psy-rd} options that use ":" as a separator
yading@10: themselves, use "," instead. They accept it as well since long ago but this
yading@10: is kept undocumented for some reason.
yading@10: 
yading@10: For example to specify libx264 encoding options with @command{ffmpeg}:
yading@10: @example
yading@10: ffmpeg -i foo.mpg -vcodec libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv
yading@10: @end example
yading@10: 
yading@10: For more information about libx264 and the supported options see:
yading@10: @url{http://www.videolan.org/developers/x264.html}
yading@10: 
yading@10: @item -x264-params @var{string}
yading@10: Override the x264 configuration using a :-separated list of key=value parameters.
yading@10: @example
yading@10: -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
yading@10: @end example
yading@10: @end table
yading@10: 
yading@10: Encoding avpresets for common usages are provided so they can be used with the
yading@10: general presets system (e.g. passing the @code{-pre} option).
yading@10: 
yading@10: @section ProRes
yading@10: 
yading@10: Apple ProRes encoder.
yading@10: 
yading@10: FFmpeg contains 2 ProRes encoders, the prores-aw and prores-ks encoder.
yading@10: The used encoder can be choosen with the @code{-vcodec} option.
yading@10: 
yading@10: @subsection Private Options for prores-ks
yading@10: 
yading@10: @table @option
yading@10: @item profile @var{integer}
yading@10: Select the ProRes profile to encode
yading@10: @table @samp
yading@10: @item proxy
yading@10: @item lt
yading@10: @item standard
yading@10: @item hq
yading@10: @end table
yading@10: 
yading@10: @item quant_mat @var{integer}
yading@10: Select quantization matrix.
yading@10: @table @samp
yading@10: @item auto
yading@10: @item default
yading@10: @item proxy
yading@10: @item lt
yading@10: @item standard
yading@10: @item hq
yading@10: @end table
yading@10: If set to @var{auto}, the matrix matching the profile will be picked.
yading@10: If not set, the matrix providing the highest quality, @var{default}, will be
yading@10: picked.
yading@10: 
yading@10: @item bits_per_mb @var{integer}
yading@10: How many bits to allot for coding one macroblock. Different profiles use
yading@10: between 200 and 2400 bits per macroblock, the maximum is 8000.
yading@10: 
yading@10: @item mbs_per_slice @var{integer}
yading@10: Number of macroblocks in each slice (1-8); the default value (8)
yading@10: should be good in almost all situations.
yading@10: 
yading@10: @item vendor @var{string}
yading@10: Override the 4-byte vendor ID.
yading@10: A custom vendor ID like @var{apl0} would claim the stream was produced by
yading@10: the Apple encoder.
yading@10: 
yading@10: @end table
yading@10: 
yading@10: @subsection Speed considerations
yading@10: 
yading@10: In the default mode of operation the encoder has to honor frame constraints
yading@10: (i.e. not produc frames with size bigger than requested) while still making
yading@10: output picture as good as possible.
yading@10: A frame containing a lot of small details is harder to compress and the encoder
yading@10: would spend more time searching for appropriate quantizers for each slice.
yading@10: 
yading@10: Setting a higher @option{bits_per_mb} limit will improve the speed.
yading@10: 
yading@10: For the fastest encoding speed set the @option{qscale} parameter (4 is the
yading@10: recommended value) and do not set a size constraint.
yading@10: 
yading@10: @c man end VIDEO ENCODERS