@anchor{codec-options}

 @chapter Codec Options
 @c man begin CODEC OPTIONS
 
 libavcodec provides some generic global options, which can be set on
 all the encoders and decoders. In addition each codec may support
 so-called private options, which are specific for a given codec.
 
 Sometimes, a global option may only affect a specific kind of codec,

 and may be nonsensical or ignored by another, so you need to be aware

 of the meaning of the specified options. Also some options are
 meant only for decoding or encoding.
 
 Options may be set by specifying -@var{option} @var{value} in the
 FFmpeg tools, or by setting the value explicitly in the
 @code{AVCodecContext} options or using the @file{libavutil/opt.h} API
 for programmatic use.
 
 The list of supported options follow:
 
 @table @option
 @item b @var{integer} (@emph{encoding,audio,video})
 Set bitrate in bits/s. Default value is 200K.
 
 @item ab @var{integer} (@emph{encoding,audio})
 Set audio bitrate (in bits/s). Default value is 128K.
 
 @item bt @var{integer} (@emph{encoding,video})
 Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate
 tolerance specifies how far ratecontrol is willing to deviate from the
 target average bitrate value. This is not related to min/max
 bitrate. Lowering tolerance too much has an adverse effect on quality.
 
 @item flags @var{flags} (@emph{decoding/encoding,audio,video,subtitles})
 Set generic flags.
 
 Possible values:
 @table @samp
 @item mv4
 Use four motion vector by macroblock (mpeg4).
 @item qpel
 Use 1/4 pel motion compensation.
 @item loop
 Use loop filter.
 @item qscale
 Use fixed qscale.
 @item gmc
 Use gmc.
 @item mv0
 Always try a mb with mv=<0,0>.
 @item input_preserved
 
 @item pass1
 Use internal 2pass ratecontrol in first pass mode.
 @item pass2
 Use internal 2pass ratecontrol in second pass mode.
 @item gray
 Only decode/encode grayscale.
 @item emu_edge
 Do not draw edges.
 @item psnr
 Set error[?] variables during encoding.
 @item truncated
 
 @item naq
 Normalize adaptive quantization.
 @item ildct
 Use interlaced DCT.
 @item low_delay
 Force low delay.
 @item global_header
 Place global headers in extradata instead of every keyframe.
 @item bitexact

 Only write platform-, build- and time-independent data. (except (I)DCT).

 This ensures that file and data checksums are reproducible and match between

 platforms. Its primary use is for regression testing.

 @item aic
 Apply H263 advanced intra coding / mpeg4 ac prediction.
 @item cbp
 Deprecated, use mpegvideo private options instead.
 @item qprd
 Deprecated, use mpegvideo private options instead.
 @item ilme
 Apply interlaced motion estimation.
 @item cgop
 Use closed gop.
 @end table
 
 @item me_method @var{integer} (@emph{encoding,video})
 Set motion estimation method.
 
 Possible values:
 @table @samp
 @item zero
 zero motion estimation (fastest)
 @item full
 full motion estimation (slowest)
 @item epzs
 EPZS motion estimation (default)
 @item esa
 esa motion estimation (alias for full)
 @item tesa
 tesa motion estimation
 @item dia
 dia motion estimation (alias for epzs)
 @item log
 log motion estimation
 @item phods
 phods motion estimation
 @item x1
 X1 motion estimation
 @item hex
 hex motion estimation
 @item umh
 umh motion estimation
 @item iter
 iter motion estimation
 @end table
 
 @item extradata_size @var{integer}
 Set extradata size.
 
 @item time_base @var{rational number}
 Set codec time base.
 
 It is the fundamental unit of time (in seconds) in terms of which
 frame timestamps are represented. For fixed-fps content, timebase
 should be @code{1 / frame_rate} and timestamp increments should be
 identically 1.
 
 @item g @var{integer} (@emph{encoding,video})
 Set the group of picture size. Default value is 12.
 
 @item ar @var{integer} (@emph{decoding/encoding,audio})
 Set audio sampling rate (in Hz).
 
 @item ac @var{integer} (@emph{decoding/encoding,audio})
 Set number of audio channels.
 
 @item cutoff @var{integer} (@emph{encoding,audio})
 Set cutoff bandwidth.
 
 @item frame_size @var{integer} (@emph{encoding,audio})
 Set audio frame size.
 
 Each submitted frame except the last must contain exactly frame_size
 samples per channel. May be 0 when the codec has
 CODEC_CAP_VARIABLE_FRAME_SIZE set, in that case the frame size is not
 restricted. It is set by some decoders to indicate constant frame
 size.
 
 @item frame_number @var{integer}
 Set the frame number.
 
 @item delay @var{integer}
 
 @item qcomp @var{float} (@emph{encoding,video})
 Set video quantizer scale compression (VBR). It is used as a constant
 in the ratecontrol equation. Recommended range for default rc_eq:
 0.0-1.0.
 
 @item qblur @var{float} (@emph{encoding,video})
 Set video quantizer scale blur (VBR).
 
 @item qmin @var{integer} (@emph{encoding,video})
 Set min video quantizer scale (VBR). Must be included between -1 and
 69, default value is 2.
 
 @item qmax @var{integer} (@emph{encoding,video})
 Set max video quantizer scale (VBR). Must be included between -1 and
 1024, default value is 31.
 
 @item qdiff @var{integer} (@emph{encoding,video})
 Set max difference between the quantizer scale (VBR).
 
 @item bf @var{integer} (@emph{encoding,video})

 Set max number of B frames between non-B-frames.
 
 Must be an integer between -1 and 16. 0 means that B-frames are
 disabled. If a value of -1 is used, it will choose an automatic value
 depending on the encoder.
 
 Default value is 0.

 
 @item b_qfactor @var{float} (@emph{encoding,video})
 Set qp factor between P and B frames.
 
 @item rc_strategy @var{integer} (@emph{encoding,video})
 Set ratecontrol method.
 
 @item b_strategy @var{integer} (@emph{encoding,video})
 Set strategy to choose between I/P/B-frames.
 
 @item ps @var{integer} (@emph{encoding,video})
 Set RTP payload size in bytes.
 
 @item mv_bits @var{integer}
 @item header_bits @var{integer}
 @item i_tex_bits @var{integer}
 @item p_tex_bits @var{integer}
 @item i_count @var{integer}
 @item p_count @var{integer}
 @item skip_count @var{integer}
 @item misc_bits @var{integer}
 @item frame_bits @var{integer}
 @item codec_tag @var{integer}
 @item bug @var{flags} (@emph{decoding,video})
 Workaround not auto detected encoder bugs.
 
 Possible values:
 @table @samp
 @item autodetect
 
 @item old_msmpeg4
 some old lavc generated msmpeg4v3 files (no autodetection)
 @item xvid_ilace
 Xvid interlacing bug (autodetected if fourcc==XVIX)
 @item ump4
 (autodetected if fourcc==UMP4)
 @item no_padding
 padding bug (autodetected)
 @item amv
 
 @item ac_vlc
 illegal vlc bug (autodetected per fourcc)
 @item qpel_chroma
 
 @item std_qpel
 old standard qpel (autodetected per fourcc/version)
 @item qpel_chroma2
 
 @item direct_blocksize
 direct-qpel-blocksize bug (autodetected per fourcc/version)
 @item edge
 edge padding bug (autodetected per fourcc/version)
 @item hpel_chroma
 
 @item dc_clip
 
 @item ms
 Workaround various bugs in microsoft broken decoders.
 @item trunc
 trancated frames
 @end table
 
 @item lelim @var{integer} (@emph{encoding,video})
 Set single coefficient elimination threshold for luminance (negative
 values also consider DC coefficient).
 
 @item celim @var{integer} (@emph{encoding,video})
 Set single coefficient elimination threshold for chrominance (negative
 values also consider dc coefficient)
 
 @item strict @var{integer} (@emph{decoding/encoding,audio,video})
 Specify how strictly to follow the standards.
 
 Possible values:
 @table @samp
 @item very
 strictly conform to a older more strict version of the spec or reference software
 @item strict
 strictly conform to all the things in the spec no matter what consequences
 @item normal
 
 @item unofficial
 allow unofficial extensions
 @item experimental

 allow non standardized experimental things, experimental
 (unfinished/work in progress/not well tested) decoders and encoders.
 Note: experimental decoders can pose a security risk, do not use this for
 decoding untrusted input.

 @end table
 
 @item b_qoffset @var{float} (@emph{encoding,video})
 Set QP offset between P and B frames.
 
 @item err_detect @var{flags} (@emph{decoding,audio,video})
 Set error detection flags.
 
 Possible values:
 @table @samp
 @item crccheck
 verify embedded CRCs
 @item bitstream
 detect bitstream specification deviations
 @item buffer
 detect improper bitstream length
 @item explode
 abort decoding on minor error detection

 @item ignore_err
 ignore decoding errors, and continue decoding.
 This is useful if you want to analyze the content of a video and thus want
 everything to be decoded no matter what. This option will not result in a video
 that is pleasing to watch in case of errors.

 @item careful
 consider things that violate the spec and have not been seen in the wild as errors
 @item compliant
 consider all spec non compliancies as errors
 @item aggressive
 consider things that a sane encoder should not do as an error
 @end table
 
 @item has_b_frames @var{integer}
 
 @item block_align @var{integer}
 
 @item mpeg_quant @var{integer} (@emph{encoding,video})
 Use MPEG quantizers instead of H.263.
 
 @item qsquish @var{float} (@emph{encoding,video})
 How to keep quantizer between qmin and qmax (0 = clip, 1 = use
 differentiable function).
 
 @item rc_qmod_amp @var{float} (@emph{encoding,video})
 Set experimental quantizer modulation.
 
 @item rc_qmod_freq @var{integer} (@emph{encoding,video})
 Set experimental quantizer modulation.
 
 @item rc_override_count @var{integer}
 
 @item rc_eq @var{string} (@emph{encoding,video})
 Set rate control equation. When computing the expression, besides the
 standard functions defined in the section 'Expression Evaluation', the
 following functions are available: bits2qp(bits), qp2bits(qp). Also
 the following constants are available: iTex pTex tex mv fCode iCount
 mcVar var isI isP isB avgQP qComp avgIITex avgPITex avgPPTex avgBPTex
 avgTex.
 
 @item maxrate @var{integer} (@emph{encoding,audio,video})
 Set max bitrate tolerance (in bits/s). Requires bufsize to be set.
 
 @item minrate @var{integer} (@emph{encoding,audio,video})
 Set min bitrate tolerance (in bits/s). Most useful in setting up a CBR
 encode. It is of little use elsewise.
 
 @item bufsize @var{integer} (@emph{encoding,audio,video})
 Set ratecontrol buffer size (in bits).
 
 @item rc_buf_aggressivity @var{float} (@emph{encoding,video})
 Currently useless.
 
 @item i_qfactor @var{float} (@emph{encoding,video})
 Set QP factor between P and I frames.
 
 @item i_qoffset @var{float} (@emph{encoding,video})
 Set QP offset between P and I frames.
 
 @item rc_init_cplx @var{float} (@emph{encoding,video})
 Set initial complexity for 1-pass encoding.
 
 @item dct @var{integer} (@emph{encoding,video})
 Set DCT algorithm.
 
 Possible values:
 @table @samp
 @item auto
 autoselect a good one (default)
 @item fastint
 fast integer
 @item int
 accurate integer
 @item mmx
 
 @item altivec
 
 @item faan
 floating point AAN DCT
 @end table
 
 @item lumi_mask @var{float} (@emph{encoding,video})
 Compress bright areas stronger than medium ones.
 
 @item tcplx_mask @var{float} (@emph{encoding,video})
 Set temporal complexity masking.
 
 @item scplx_mask @var{float} (@emph{encoding,video})
 Set spatial complexity masking.
 
 @item p_mask @var{float} (@emph{encoding,video})
 Set inter masking.
 
 @item dark_mask @var{float} (@emph{encoding,video})
 Compress dark areas stronger than medium ones.
 
 @item idct @var{integer} (@emph{decoding/encoding,video})
 Select IDCT implementation.
 
 Possible values:
 @table @samp
 @item auto
 
 @item int
 
 @item simple
 
 @item simplemmx
 

 @item simpleauto
 Automatically pick a IDCT compatible with the simple one
 

 @item arm
 
 @item altivec
 
 @item sh4
 
 @item simplearm
 
 @item simplearmv5te
 
 @item simplearmv6
 
 @item simpleneon
 
 @item simplealpha
 
 @item ipp
 
 @item xvidmmx
 
 @item faani
 floating point AAN IDCT
 @end table
 
 @item slice_count @var{integer}
 
 @item ec @var{flags} (@emph{decoding,video})
 Set error concealment strategy.
 
 Possible values:
 @table @samp
 @item guess_mvs
 iterative motion vector (MV) search (slow)
 @item deblock
 use strong deblock filter for damaged MBs

 @item favor_inter
 favor predicting from the previous frame instead of the current

 @end table
 
 @item bits_per_coded_sample @var{integer}
 
 @item pred @var{integer} (@emph{encoding,video})
 Set prediction method.
 
 Possible values:
 @table @samp
 @item left
 
 @item plane
 
 @item median
 
 @end table
 
 @item aspect @var{rational number} (@emph{encoding,video})
 Set sample aspect ratio.
 
 @item debug @var{flags} (@emph{decoding/encoding,audio,video,subtitles})
 Print specific debug info.
 
 Possible values:
 @table @samp
 @item pict
 picture info
 @item rc
 rate control
 @item bitstream
 
 @item mb_type
 macroblock (MB) type
 @item qp
 per-block quantization parameter (QP)
 @item mv
 motion vector
 @item dct_coeff
 

 @item green_metadata
 display complexity metadata for the upcoming frame, GoP or for a given duration.
 

 @item skip
 
 @item startcode
 
 @item pts
 
 @item er
 error recognition
 @item mmco
 memory management control operations (H.264)
 @item bugs
 
 @item vis_qp
 visualize quantization parameter (QP), lower QP are tinted greener
 @item vis_mb_type
 visualize block types
 @item buffers
 picture buffer allocations
 @item thread_ops
 threading operations

 @item nomc
 skip motion compensation

 @end table
 
 @item vismv @var{integer} (@emph{decoding,video})
 Visualize motion vectors (MVs).
 

 This option is deprecated, see the codecview filter instead.
 

 Possible values:
 @table @samp
 @item pf
 forward predicted MVs of P-frames
 @item bf
 forward predicted MVs of B-frames
 @item bb
 backward predicted MVs of B-frames
 @end table
 
 @item cmp @var{integer} (@emph{encoding,video})
 Set full pel me compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item subcmp @var{integer} (@emph{encoding,video})
 Set sub pel me compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item mbcmp @var{integer} (@emph{encoding,video})
 Set macroblock compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item ildctcmp @var{integer} (@emph{encoding,video})
 Set interlaced dct compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item dia_size @var{integer} (@emph{encoding,video})
 Set diamond type & size for motion estimation.
 
 @item last_pred @var{integer} (@emph{encoding,video})
 Set amount of motion predictors from the previous frame.
 
 @item preme @var{integer} (@emph{encoding,video})
 Set pre motion estimation.
 
 @item precmp @var{integer} (@emph{encoding,video})
 Set pre motion estimation compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item pre_dia_size @var{integer} (@emph{encoding,video})
 Set diamond type & size for motion estimation pre-pass.
 
 @item subq @var{integer} (@emph{encoding,video})
 Set sub pel motion estimation quality.
 
 @item dtg_active_format @var{integer}
 
 @item me_range @var{integer} (@emph{encoding,video})
 Set limit motion vectors range (1023 for DivX player).
 
 @item ibias @var{integer} (@emph{encoding,video})
 Set intra quant bias.
 
 @item pbias @var{integer} (@emph{encoding,video})
 Set inter quant bias.
 
 @item color_table_id @var{integer}
 
 @item global_quality @var{integer} (@emph{encoding,audio,video})
 
 @item coder @var{integer} (@emph{encoding,video})
 
 Possible values:
 @table @samp
 @item vlc
 variable length coder / huffman coder
 @item ac
 arithmetic coder
 @item raw
 raw (no encoding)
 @item rle
 run-length coder
 @item deflate
 deflate-based coder
 @end table
 
 @item context @var{integer} (@emph{encoding,video})
 Set context model.
 
 @item slice_flags @var{integer}
 
 @item xvmc_acceleration @var{integer}
 
 @item mbd @var{integer} (@emph{encoding,video})
 Set macroblock decision algorithm (high quality mode).
 
 Possible values:
 @table @samp
 @item simple
 use mbcmp (default)
 @item bits
 use fewest bits
 @item rd
 use best rate distortion
 @end table
 
 @item stream_codec_tag @var{integer}
 
 @item sc_threshold @var{integer} (@emph{encoding,video})
 Set scene change threshold.
 
 @item lmin @var{integer} (@emph{encoding,video})
 Set min lagrange factor (VBR).
 
 @item lmax @var{integer} (@emph{encoding,video})
 Set max lagrange factor (VBR).
 
 @item nr @var{integer} (@emph{encoding,video})
 Set noise reduction.
 
 @item rc_init_occupancy @var{integer} (@emph{encoding,video})
 Set number of bits which should be loaded into the rc buffer before
 decoding starts.
 
 @item flags2 @var{flags} (@emph{decoding/encoding,audio,video})
 
 Possible values:
 @table @samp
 @item fast

 Allow non spec compliant speedup tricks.

 @item sgop

 Deprecated, use mpegvideo private options instead.

 @item noout

 Skip bitstream encoding.

 @item ignorecrop
 Ignore cropping information from sps.

 @item local_header

 Place global headers at every keyframe instead of in extradata.

 @item chunks

 Frame data might be split into multiple chunks.

 @item showall

 Show all frames before the first keyframe.

 @item skiprd

 Deprecated, use mpegvideo private options instead.

 @item export_mvs
 Export motion vectors into frame side-data (see @code{AV_FRAME_DATA_MOTION_VECTORS})
 for codecs that support it. See also @file{doc/examples/export_mvs.c}.

 @end table
 
 @item error @var{integer} (@emph{encoding,video})
 
 @item qns @var{integer} (@emph{encoding,video})
 Deprecated, use mpegvideo private options instead.
 
 @item threads @var{integer} (@emph{decoding/encoding,video})
 
 Possible values:
 @table @samp
 @item auto
 detect a good number of threads
 @end table
 
 @item me_threshold @var{integer} (@emph{encoding,video})
 Set motion estimation threshold.
 
 @item mb_threshold @var{integer} (@emph{encoding,video})
 Set macroblock threshold.
 
 @item dc @var{integer} (@emph{encoding,video})
 Set intra_dc_precision.
 
 @item nssew @var{integer} (@emph{encoding,video})
 Set nsse weight.
 
 @item skip_top @var{integer} (@emph{decoding,video})
 Set number of macroblock rows at the top which are skipped.
 
 @item skip_bottom @var{integer} (@emph{decoding,video})
 Set number of macroblock rows at the bottom which are skipped.
 
 @item profile @var{integer} (@emph{encoding,audio,video})
 
 Possible values:
 @table @samp
 @item unknown
 
 @item aac_main
 
 @item aac_low
 
 @item aac_ssr
 
 @item aac_ltp
 
 @item aac_he
 
 @item aac_he_v2
 
 @item aac_ld
 
 @item aac_eld
 

 @item mpeg2_aac_low
 
 @item mpeg2_aac_he
 

 @item mpeg4_sp
 
 @item mpeg4_core
 
 @item mpeg4_main
 
 @item mpeg4_asp
 

 @item dts
 
 @item dts_es
 
 @item dts_96_24
 
 @item dts_hd_hra
 
 @item dts_hd_ma
 
 @end table
 
 @item level @var{integer} (@emph{encoding,audio,video})
 
 Possible values:
 @table @samp
 @item unknown
 
 @end table
 
 @item lowres @var{integer} (@emph{decoding,audio,video})
 Decode at 1= 1/2, 2=1/4, 3=1/8 resolutions.
 
 @item skip_threshold @var{integer} (@emph{encoding,video})
 Set frame skip threshold.
 
 @item skip_factor @var{integer} (@emph{encoding,video})
 Set frame skip factor.
 
 @item skip_exp @var{integer} (@emph{encoding,video})
 Set frame skip exponent.

 Negative values behave identical to the corresponding positive ones, except
 that the score is normalized.

 Positive values exist primarily for compatibility reasons and are not so useful.

 
 @item skipcmp @var{integer} (@emph{encoding,video})
 Set frame skip compare function.
 
 Possible values:
 @table @samp
 @item sad
 sum of absolute differences, fast (default)
 @item sse
 sum of squared errors
 @item satd
 sum of absolute Hadamard transformed differences
 @item dct
 sum of absolute DCT transformed differences
 @item psnr
 sum of squared quantization errors (avoid, low quality)
 @item bit
 number of bits needed for the block
 @item rd
 rate distortion optimal, slow
 @item zero
 0
 @item vsad
 sum of absolute vertical differences
 @item vsse
 sum of squared vertical differences
 @item nsse
 noise preserving sum of squared differences
 @item w53
 5/3 wavelet, only used in snow
 @item w97
 9/7 wavelet, only used in snow
 @item dctmax
 
 @item chroma
 
 @end table
 
 @item border_mask @var{float} (@emph{encoding,video})
 Increase the quantizer for macroblocks close to borders.
 
 @item mblmin @var{integer} (@emph{encoding,video})
 Set min macroblock lagrange factor (VBR).
 
 @item mblmax @var{integer} (@emph{encoding,video})
 Set max macroblock lagrange factor (VBR).
 
 @item mepc @var{integer} (@emph{encoding,video})
 Set motion estimation bitrate penalty compensation (1.0 = 256).
 
 @item skip_loop_filter @var{integer} (@emph{decoding,video})
 @item skip_idct        @var{integer} (@emph{decoding,video})
 @item skip_frame       @var{integer} (@emph{decoding,video})
 
 Make decoder discard processing depending on the frame type selected
 by the option value.
 
 @option{skip_loop_filter} skips frame loop filtering, @option{skip_idct}
 skips frame IDCT/dequantization, @option{skip_frame} skips decoding.
 
 Possible values:
 @table @samp
 @item none
 Discard no frame.
 
 @item default
 Discard useless frames like 0-sized frames.
 
 @item noref
 Discard all non-reference frames.
 
 @item bidir
 Discard all bidirectional frames.
 
 @item nokey
 Discard all frames excepts keyframes.
 
 @item all
 Discard all frames.
 @end table
 
 Default value is @samp{default}.
 
 @item bidir_refine @var{integer} (@emph{encoding,video})
 Refine the two motion vectors used in bidirectional macroblocks.
 
 @item brd_scale @var{integer} (@emph{encoding,video})
 Downscale frames for dynamic B-frame decision.
 
 @item keyint_min @var{integer} (@emph{encoding,video})
 Set minimum interval between IDR-frames.
 
 @item refs @var{integer} (@emph{encoding,video})
 Set reference frames to consider for motion compensation.
 
 @item chromaoffset @var{integer} (@emph{encoding,video})
 Set chroma qp offset from luma.
 
 @item trellis @var{integer} (@emph{encoding,audio,video})
 Set rate-distortion optimal quantization.
 
 @item sc_factor @var{integer} (@emph{encoding,video})
 Set value multiplied by qscale for each frame and added to
 scene_change_score.
 
 @item mv0_threshold @var{integer} (@emph{encoding,video})
 @item b_sensitivity @var{integer} (@emph{encoding,video})
 Adjust sensitivity of b_frame_strategy 1.
 
 @item compression_level @var{integer} (@emph{encoding,audio,video})
 @item min_prediction_order @var{integer} (@emph{encoding,audio})
 @item max_prediction_order @var{integer} (@emph{encoding,audio})
 @item timecode_frame_start @var{integer} (@emph{encoding,video})
 Set GOP timecode frame start number, in non drop frame format.
 
 @item request_channels @var{integer} (@emph{decoding,audio})
 Set desired number of audio channels.
 
 @item bits_per_raw_sample @var{integer}
 @item channel_layout @var{integer} (@emph{decoding/encoding,audio})
 
 Possible values:
 @table @samp
 @end table
 @item request_channel_layout @var{integer} (@emph{decoding,audio})
 
 Possible values:
 @table @samp
 @end table
 @item rc_max_vbv_use @var{float} (@emph{encoding,video})
 @item rc_min_vbv_use @var{float} (@emph{encoding,video})
 @item ticks_per_frame @var{integer} (@emph{decoding/encoding,audio,video})
 @item color_primaries @var{integer} (@emph{decoding/encoding,video})
 @item color_trc @var{integer} (@emph{decoding/encoding,video})
 @item colorspace @var{integer} (@emph{decoding/encoding,video})

 @item color_range @var{integer} (@emph{decoding/encoding,video})

 If used as input parameter, it serves as a hint to the decoder, which
 color_range the input has.
 

 @item chroma_sample_location @var{integer} (@emph{decoding/encoding,video})
 
 @item log_level_offset @var{integer}
 Set the log level offset.
 
 @item slices @var{integer} (@emph{encoding,video})
 Number of slices, used in parallelized encoding.
 
 @item thread_type @var{flags} (@emph{decoding/encoding,video})

 Select which multithreading methods to use.
 
 Use of @samp{frame} will increase decoding delay by one frame per
 thread, so clients which cannot provide future frames should not use
 it.

 
 Possible values:
 @table @samp
 @item slice

 Decode more than one part of a single frame at once.

 Multithreading using slices works only when the video was encoded with
 slices.

 @item frame
 Decode more than one frame at once.

 @end table

 
 Default value is @samp{slice+frame}.
 

 @item audio_service_type @var{integer} (@emph{encoding,audio})
 Set audio service type.
 
 Possible values:
 @table @samp
 @item ma
 Main Audio Service
 @item ef
 Effects
 @item vi
 Visually Impaired
 @item hi
 Hearing Impaired
 @item di
 Dialogue
 @item co
 Commentary
 @item em
 Emergency
 @item vo
 Voice Over
 @item ka
 Karaoke
 @end table
 
 @item request_sample_fmt @var{sample_fmt} (@emph{decoding,audio})
 Set sample format audio decoders should prefer. Default value is
 @code{none}.
 
 @item pkt_timebase @var{rational number}
 
 @item sub_charenc @var{encoding} (@emph{decoding,subtitles})
 Set the input subtitles character encoding.

 
 @item field_order  @var{field_order} (@emph{video})
 Set/override the field order of the video.
 Possible values:
 @table @samp
 @item progressive
 Progressive video
 @item tt
 Interlaced video, top field coded and displayed first
 @item bb
 Interlaced video, bottom field coded and displayed first
 @item tb
 Interlaced video, top coded first, bottom displayed first
 @item bt
 Interlaced video, bottom coded first, top displayed first
 @end table

 
 @item skip_alpha @var{integer} (@emph{decoding,video})

 Set to 1 to disable processing alpha (transparency). This works like the
 @samp{gray} flag in the @option{flags} option which skips chroma information
 instead of alpha. Default is 0.

 
 @item codec_whitelist @var{list} (@emph{input})
 "," separated List of allowed decoders. By default all are allowed.
 

 @item dump_separator @var{string} (@emph{input})
 Separator used to separate the fields printed on the command line about the
 Stream parameters.
 For example to separate the fields with newlines and indention:
 @example
 ffprobe -dump_separator "
                           "  -i ~/videos/matrixbench_mpeg2.mpg
 @end example
 

 @end table
 
 @c man end CODEC OPTIONS
 

 @ifclear config-writeonly

 @include decoders.texi

 @end ifclear
 @ifclear config-readonly

 @include encoders.texi

 @end ifclear