# phpman > man > ffmpeg-codecs(1)

[FFMPEG-CODECS(1)](https://www.chedong.com/phpMan.php/man/FFMPEG-CODECS/1/markdown)                                                                    [FFMPEG-CODECS(1)](https://www.chedong.com/phpMan.php/man/FFMPEG-CODECS/1/markdown)



## NAME
       ffmpeg-codecs - FFmpeg codecs

## DESCRIPTION
       This document describes the codecs (decoders and encoders) provided by the libavcodec
       library.

## 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 -_option_ _value_ in the FFmpeg tools, or by setting the value
       explicitly in the "AVCodecContext" options or using the _libavutil/opt.h_ API for programmatic
       use.

       The list of supported options follow:

       **b** _integer_ **(**_encoding,audio,video_**)**
           Set bitrate in bits/s. Default value is 200K.

       **ab** _integer_ **(**_encoding,audio_**)**
           Set audio bitrate (in bits/s). Default value is 128K.

       **bt** _integer_ **(**_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.

       **flags** _flags_ **(**_decoding/encoding,audio,video,subtitles_**)**
           Set generic flags.

           Possible values:

           **mv4** Use four motion vector by macroblock (mpeg4).

           **qpel**
               Use 1/4 pel motion compensation.

           **loop**
               Use loop filter.

           **qscale**
               Use fixed qscale.

           **pass1**
               Use internal 2pass ratecontrol in first pass mode.

           **pass2**
               Use internal 2pass ratecontrol in second pass mode.

           **gray**
               Only decode/encode grayscale.

           **psnr**
               Set error[?] variables during encoding.

           **truncated**
               Input bitstream might be randomly truncated.

           **drop**___**changed**
               Don't output frames whose parameters differ from first decoded frame in stream.
               Error AVERROR_INPUT_CHANGED is returned when a frame is dropped.

           **ildct**
               Use interlaced DCT.

           **low**___**delay**
               Force low delay.

           **global**___**header**
               Place global headers in extradata instead of every keyframe.

           **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.

           **aic** Apply H263 advanced intra coding / mpeg4 ac prediction.

           **ilme**
               Apply interlaced motion estimation.

           **cgop**
               Use closed gop.

           **output**___**corrupt**
               Output even potentially corrupted frames.

       **time**___**base** _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 "1 / frame_rate" and timestamp
           increments should be identically 1.

       **g** _integer_ **(**_encoding,video_**)**
           Set the group of picture (GOP) size. Default value is 12.

       **ar** _integer_ **(**_decoding/encoding,audio_**)**
           Set audio sampling rate (in Hz).

       **ac** _integer_ **(**_decoding/encoding,audio_**)**
           Set number of audio channels.

       **cutoff** _integer_ **(**_encoding,audio_**)**
           Set cutoff bandwidth. (Supported only by selected encoders, see their respective
           documentation sections.)

       **frame**___**size** _integer_ **(**_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.

       **frame**___**number** _integer_
           Set the frame number.

       **delay** _integer_
       **qcomp** _float_ **(**_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.

       **qblur** _float_ **(**_encoding,video_**)**
           Set video quantizer scale blur (VBR).

       **qmin** _integer_ **(**_encoding,video_**)**
           Set min video quantizer scale (VBR). Must be included between -1 and 69, default value is
           2.

       **qmax** _integer_ **(**_encoding,video_**)**
           Set max video quantizer scale (VBR). Must be included between -1 and 1024, default value
           is 31.

       **qdiff** _integer_ **(**_encoding,video_**)**
           Set max difference between the quantizer scale (VBR).

       **bf** _integer_ **(**_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.

       **b**___**qfactor** _float_ **(**_encoding,video_**)**
           Set qp factor between P and B frames.

       **b**___**strategy** _integer_ **(**_encoding,video_**)**
           Set strategy to choose between I/P/B-frames.

       **ps** _integer_ **(**_encoding,video_**)**
           Set RTP payload size in bytes.

       **mv**___**bits** _integer_
       **header**___**bits** _integer_
       **i**___**tex**___**bits** _integer_
       **p**___**tex**___**bits** _integer_
       **i**___**count** _integer_
       **p**___**count** _integer_
       **skip**___**count** _integer_
       **misc**___**bits** _integer_
       **frame**___**bits** _integer_
       **codec**___**tag** _integer_
       **bug** _flags_ **(**_decoding,video_**)**
           Workaround not auto detected encoder bugs.

           Possible values:

           **autodetect**
           **xvid**___**ilace**
               Xvid interlacing bug (autodetected if fourcc==XVIX)

           **ump4**
               (autodetected if fourcc==UMP4)

           **no**___**padding**
               padding bug (autodetected)

           **amv**
           **qpel**___**chroma**
           **std**___**qpel**
               old standard qpel (autodetected per fourcc/version)

           **qpel**___**chroma2**
           **direct**___**blocksize**
               direct-qpel-blocksize bug (autodetected per fourcc/version)

           **edge**
               edge padding bug (autodetected per fourcc/version)

           **hpel**___**chroma**
           **dc**___**clip**
           **ms**  Workaround various bugs in microsoft broken decoders.

           **trunc**
               trancated frames

       **strict** _integer_ **(**_decoding/encoding,audio,video_**)**
           Specify how strictly to follow the standards.

           Possible values:

           **very**
               strictly conform to an older more strict version of the spec or reference software

           **strict**
               strictly conform to all the things in the spec no matter what consequences

           **normal**
           **unofficial**
               allow unofficial extensions

           **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.

       **b**___**qoffset** _float_ **(**_encoding,video_**)**
           Set QP offset between P and B frames.

       **err**___**detect** _flags_ **(**_decoding,audio,video_**)**
           Set error detection flags.

           Possible values:

           **crccheck**
               verify embedded CRCs

           **bitstream**
               detect bitstream specification deviations

           **buffer**
               detect improper bitstream length

           **explode**
               abort decoding on minor error detection

           **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.

           **careful**
               consider things that violate the spec and have not been seen in the wild as errors

           **compliant**
               consider all spec non compliancies as errors

           **aggressive**
               consider things that a sane encoder should not do as an error

       **has**___**b**___**frames** _integer_
       **block**___**align** _integer_
       **mpeg**___**quant** _integer_ **(**_encoding,video_**)**
           Use MPEG quantizers instead of H.263.

       **rc**___**override**___**count** _integer_
       **maxrate** _integer_ **(**_encoding,audio,video_**)**
           Set max bitrate tolerance (in bits/s). Requires bufsize to be set.

       **minrate** _integer_ **(**_encoding,audio,video_**)**
           Set min bitrate tolerance (in bits/s). Most useful in setting up a CBR encode. It is of
           little use elsewise.

       **bufsize** _integer_ **(**_encoding,audio,video_**)**
           Set ratecontrol buffer size (in bits).

       **i**___**qfactor** _float_ **(**_encoding,video_**)**
           Set QP factor between P and I frames.

       **i**___**qoffset** _float_ **(**_encoding,video_**)**
           Set QP offset between P and I frames.

       **dct** _integer_ **(**_encoding,video_**)**
           Set DCT algorithm.

           Possible values:

           **auto**
               autoselect a good one (default)

           **fastint**
               fast integer

           **int** accurate integer

           **mmx**
           **altivec**
           **faan**
               floating point AAN DCT

       **lumi**___**mask** _float_ **(**_encoding,video_**)**
           Compress bright areas stronger than medium ones.

       **tcplx**___**mask** _float_ **(**_encoding,video_**)**
           Set temporal complexity masking.

       **scplx**___**mask** _float_ **(**_encoding,video_**)**
           Set spatial complexity masking.

       **p**___**mask** _float_ **(**_encoding,video_**)**
           Set inter masking.

       **dark**___**mask** _float_ **(**_encoding,video_**)**
           Compress dark areas stronger than medium ones.

       **idct** _integer_ **(**_decoding/encoding,video_**)**
           Select IDCT implementation.

           Possible values:

           **auto**
           **int**
           **simple**
           **simplemmx**
           **simpleauto**
               Automatically pick a IDCT compatible with the simple one

           **arm**
           **altivec**
           **sh4**
           **simplearm**
           **simplearmv5te**
           **simplearmv6**
           **simpleneon**
           **xvid**
           **faani**
               floating point AAN IDCT

       **slice**___**count** _integer_
       **ec** _flags_ **(**_decoding,video_**)**
           Set error concealment strategy.

           Possible values:

           **guess**___**mvs**
               iterative motion vector (MV) search (slow)

           **deblock**
               use strong deblock filter for damaged MBs

           **favor**___**inter**
               favor predicting from the previous frame instead of the current

       **bits**___**per**___**coded**___**sample** _integer_
       **pred** _integer_ **(**_encoding,video_**)**
           Set prediction method.

           Possible values:

           **left**
           **plane**
           **median**
       **aspect** _rational_ _number_ **(**_encoding,video_**)**
           Set sample aspect ratio.

       **sar** _rational_ _number_ **(**_encoding,video_**)**
           Set sample aspect ratio. Alias to _aspect_.

       **debug** _flags_ **(**_decoding/encoding,audio,video,subtitles_**)**
           Print specific debug info.

           Possible values:

           **pict**
               picture info

           **rc**  rate control

           **bitstream**
           **mb**___**type**
               macroblock (MB) type

           **qp**  per-block quantization parameter (QP)

           **dct**___**coeff**
           **green**___**metadata**
               display complexity metadata for the upcoming frame, GoP or for a given duration.

           **skip**
           **startcode**
           **er**  error recognition

           **mmco**
               memory management control operations (H.264)

           **bugs**
           **buffers**
               picture buffer allocations

           **thread**___**ops**
               threading operations

           **nomc**
               skip motion compensation

       **cmp** _integer_ **(**_encoding,video_**)**
           Set full pel me compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **subcmp** _integer_ **(**_encoding,video_**)**
           Set sub pel me compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **mbcmp** _integer_ **(**_encoding,video_**)**
           Set macroblock compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **ildctcmp** _integer_ **(**_encoding,video_**)**
           Set interlaced dct compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **dia**___**size** _integer_ **(**_encoding,video_**)**
           Set diamond type & size for motion estimation.

           **(1024,** **INT**___**MAX)**
               full motion estimation(slowest)

           **(768,** **1024]**
               umh motion estimation

           **(512,** **768]**
               hex motion estimation

           **(256,** **512]**
               l2s diamond motion estimation

           **[2,256]**
               var diamond motion estimation

           **(-1,**  **2)**
               small diamond motion estimation

           **-1**  funny diamond motion estimation

           **(INT**___**MIN,** **-1)**
               sab diamond motion estimation

       **last**___**pred** _integer_ **(**_encoding,video_**)**
           Set amount of motion predictors from the previous frame.

       **preme** _integer_ **(**_encoding,video_**)**
           Set pre motion estimation.

       **precmp** _integer_ **(**_encoding,video_**)**
           Set pre motion estimation compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **pre**___**dia**___**size** _integer_ **(**_encoding,video_**)**
           Set diamond type & size for motion estimation pre-pass.

       **subq** _integer_ **(**_encoding,video_**)**
           Set sub pel motion estimation quality.

       **me**___**range** _integer_ **(**_encoding,video_**)**
           Set limit motion vectors range (1023 for DivX player).

       **global**___**quality** _integer_ **(**_encoding,audio,video_**)**
       **coder** _integer_ **(**_encoding,video_**)**
           Possible values:

           **vlc** variable length coder / huffman coder

           **ac**  arithmetic coder

           **raw** raw (no encoding)

           **rle** run-length coder

       **context** _integer_ **(**_encoding,video_**)**
           Set context model.

       **slice**___**flags** _integer_
       **mbd** _integer_ **(**_encoding,video_**)**
           Set macroblock decision algorithm (high quality mode).

           Possible values:

           **simple**
               use mbcmp (default)

           **bits**
               use fewest bits

           **rd**  use best rate distortion

       **sc**___**threshold** _integer_ **(**_encoding,video_**)**
           Set scene change threshold.

       **nr** _integer_ **(**_encoding,video_**)**
           Set noise reduction.

       **rc**___**init**___**occupancy** _integer_ **(**_encoding,video_**)**
           Set number of bits which should be loaded into the rc buffer before decoding starts.

       **flags2** _flags_ **(**_decoding/encoding,audio,video,subtitles_**)**
           Possible values:

           **fast**
               Allow non spec compliant speedup tricks.

           **noout**
               Skip bitstream encoding.

           **ignorecrop**
               Ignore cropping information from sps.

           **local**___**header**
               Place global headers at every keyframe instead of in extradata.

           **chunks**
               Frame data might be split into multiple chunks.

           **showall**
               Show all frames before the first keyframe.

           **export**___**mvs**
               Export motion vectors into frame side-data (see "AV_FRAME_DATA_MOTION_VECTORS") for
               codecs that support it. See also _doc/examples/export_mvs.c_.

           **skip**___**manual**
               Do not skip samples and export skip information as frame side data.

           **ass**___**ro**___**flush**___**noop**
               Do not reset ASS ReadOrder field on flush.

       **export**___**side**___**data** _flags_ **(**_decoding/encoding,audio,video,subtitles_**)**
           Possible values:

           **mvs** Export motion vectors into frame side-data (see "AV_FRAME_DATA_MOTION_VECTORS") for
               codecs that support it. See also _doc/examples/export_mvs.c_.

           **prft**
               Export encoder Producer Reference Time into packet side-data (see "AV_PKT_DATA_PRFT")
               for codecs that support it.

           **venc**___**params**
               Export video encoding parameters through frame side data (see
               "AV_FRAME_DATA_VIDEO_ENC_PARAMS") for codecs that support it. At present, those are
               H.264 and VP9.

           **film**___**grain**
               Export film grain parameters through frame side data (see
               "AV_FRAME_DATA_FILM_GRAIN_PARAMS").  Supported at present by AV1 decoders.

       **threads** _integer_ **(**_decoding/encoding,video_**)**
           Set the number of threads to be used, in case the selected codec implementation supports
           multi-threading.

           Possible values:

           **auto,** **0**
               automatically select the number of threads to set

           Default value is **auto**.

       **dc** _integer_ **(**_encoding,video_**)**
           Set intra_dc_precision.

       **nssew** _integer_ **(**_encoding,video_**)**
           Set nsse weight.

       **skip**___**top** _integer_ **(**_decoding,video_**)**
           Set number of macroblock rows at the top which are skipped.

       **skip**___**bottom** _integer_ **(**_decoding,video_**)**
           Set number of macroblock rows at the bottom which are skipped.

       **profile** _integer_ **(**_encoding,audio,video_**)**
           Set encoder codec profile. Default value is **unknown**. Encoder specific profiles are
           documented in the relevant encoder documentation.

       **level** _integer_ **(**_encoding,audio,video_**)**
           Possible values:

           **unknown**
       **lowres** _integer_ **(**_decoding,audio,video_**)**
           Decode at 1= 1/2, 2=1/4, 3=1/8 resolutions.

       **skip**___**threshold** _integer_ **(**_encoding,video_**)**
           Set frame skip threshold.

       **skip**___**factor** _integer_ **(**_encoding,video_**)**
           Set frame skip factor.

       **skip**___**exp** _integer_ **(**_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.

       **skipcmp** _integer_ **(**_encoding,video_**)**
           Set frame skip compare function.

           Possible values:

           **sad** sum of absolute differences, fast (default)

           **sse** sum of squared errors

           **satd**
               sum of absolute Hadamard transformed differences

           **dct** sum of absolute DCT transformed differences

           **psnr**
               sum of squared quantization errors (avoid, low quality)

           **bit** number of bits needed for the block

           **rd**  rate distortion optimal, slow

           **zero**
               0

           **vsad**
               sum of absolute vertical differences

           **vsse**
               sum of squared vertical differences

           **nsse**
               noise preserving sum of squared differences

           **w53** 5/3 wavelet, only used in snow

           **w97** 9/7 wavelet, only used in snow

           **dctmax**
           **chroma**
       **mblmin** _integer_ **(**_encoding,video_**)**
           Set min macroblock lagrange factor (VBR).

       **mblmax** _integer_ **(**_encoding,video_**)**
           Set max macroblock lagrange factor (VBR).

       **mepc** _integer_ **(**_encoding,video_**)**
           Set motion estimation bitrate penalty compensation (1.0 = 256).

       **skip**___**loop**___**filter** _integer_ **(**_decoding,video_**)**
       **skip**___**idct**        _integer_ **(**_decoding,video_**)**
       **skip**___**frame**       _integer_ **(**_decoding,video_**)**
           Make decoder discard processing depending on the frame type selected by the option value.

           **skip**___**loop**___**filter** skips frame loop filtering, **skip**___**idct** skips frame IDCT/dequantization,
           **skip**___**frame** skips decoding.

           Possible values:

           **none**
               Discard no frame.

           **default**
               Discard useless frames like 0-sized frames.

           **noref**
               Discard all non-reference frames.

           **bidir**
               Discard all bidirectional frames.

           **nokey**
               Discard all frames excepts keyframes.

           **nointra**
               Discard all frames except I frames.

           **all** Discard all frames.

           Default value is **default**.

       **bidir**___**refine** _integer_ **(**_encoding,video_**)**
           Refine the two motion vectors used in bidirectional macroblocks.

       **brd**___**scale** _integer_ **(**_encoding,video_**)**
           Downscale frames for dynamic B-frame decision.

       **keyint**___**min** _integer_ **(**_encoding,video_**)**
           Set minimum interval between IDR-frames.

       **refs** _integer_ **(**_encoding,video_**)**
           Set reference frames to consider for motion compensation.

       **chromaoffset** _integer_ **(**_encoding,video_**)**
           Set chroma qp offset from luma.

       **trellis** _integer_ **(**_encoding,audio,video_**)**
           Set rate-distortion optimal quantization.

       **mv0**___**threshold** _integer_ **(**_encoding,video_**)**
       **b**___**sensitivity** _integer_ **(**_encoding,video_**)**
           Adjust sensitivity of b_frame_strategy 1.

       **compression**___**level** _integer_ **(**_encoding,audio,video_**)**
       **min**___**prediction**___**order** _integer_ **(**_encoding,audio_**)**
       **max**___**prediction**___**order** _integer_ **(**_encoding,audio_**)**
       **timecode**___**frame**___**start** _integer_ **(**_encoding,video_**)**
           Set GOP timecode frame start number, in non drop frame format.

       **bits**___**per**___**raw**___**sample** _integer_
       **channel**___**layout** _integer_ **(**_decoding/encoding,audio_**)**
           Possible values:

       **request**___**channel**___**layout** _integer_ **(**_decoding,audio_**)**
           Possible values:

       **rc**___**max**___**vbv**___**use** _float_ **(**_encoding,video_**)**
       **rc**___**min**___**vbv**___**use** _float_ **(**_encoding,video_**)**
       **ticks**___**per**___**frame** _integer_ **(**_decoding/encoding,audio,video_**)**
       **color**___**primaries** _integer_ **(**_decoding/encoding,video_**)**
           Possible values:

           **bt709**
               BT.709

           **bt470m**
               BT.470 M

           **bt470bg**
               BT.470 BG

           **smpte170m**
               SMPTE 170 M

           **smpte240m**
               SMPTE 240 M

           **film**
               Film

           **bt2020**
               BT.2020

           **smpte428**
           **smpte428**___**1**
               SMPTE ST 428-1

           **smpte431**
               SMPTE 431-2

           **smpte432**
               SMPTE 432-1

           **jedec-p22**
               JEDEC P22

       **color**___**trc** _integer_ **(**_decoding/encoding,video_**)**
           Possible values:

           **bt709**
               BT.709

           **gamma22**
               BT.470 M

           **gamma28**
               BT.470 BG

           **smpte170m**
               SMPTE 170 M

           **smpte240m**
               SMPTE 240 M

           **linear**
               Linear

           **log**
           **log100**
               Log

           **log**___**sqrt**
           **log316**
               Log square root

           **iec61966**___**2**___**4**
           **iec61966-2-4**
               IEC 61966-2-4

           **bt1361**
           **bt1361e**
               BT.1361

           **iec61966**___**2**___**1**
           **iec61966-2-1**
               IEC 61966-2-1

           **bt2020**___**10**
           **bt2020**___**10bit**
               BT.2020 - 10 bit

           **bt2020**___**12**
           **bt2020**___**12bit**
               BT.2020 - 12 bit

           **smpte2084**
               SMPTE ST 2084

           **smpte428**
           **smpte428**___**1**
               SMPTE ST 428-1

           **arib-std-b67**
               ARIB STD-B67

       **colorspace** _integer_ **(**_decoding/encoding,video_**)**
           Possible values:

           **rgb** RGB

           **bt709**
               BT.709

           **fcc** FCC

           **bt470bg**
               BT.470 BG

           **smpte170m**
               SMPTE 170 M

           **smpte240m**
               SMPTE 240 M

           **ycocg**
               YCOCG

           **bt2020nc**
           **bt2020**___**ncl**
               BT.2020 NCL

           **bt2020c**
           **bt2020**___**cl**
               BT.2020 CL

           **smpte2085**
               SMPTE 2085

           **chroma-derived-nc**
               Chroma-derived NCL

           **chroma-derived-c**
               Chroma-derived CL

           **ictcp**
               ICtCp

       **color**___**range** _integer_ **(**_decoding/encoding,video_**)**
           If used as input parameter, it serves as a hint to the decoder, which color_range the
           input has.  Possible values:

           **tv**
           **mpeg**
               MPEG (219*2^(n-8))

           **pc**
           **jpeg**
               JPEG (2^n-1)

       **chroma**___**sample**___**location** _integer_ **(**_decoding/encoding,video_**)**
           Possible values:

           **left**
           **center**
           **topleft**
           **top**
           **bottomleft**
           **bottom**
       **log**___**level**___**offset** _integer_
           Set the log level offset.

       **slices** _integer_ **(**_encoding,video_**)**
           Number of slices, used in parallelized encoding.

       **thread**___**type** _flags_ **(**_decoding/encoding,video_**)**
           Select which multithreading methods to use.

           Use of **frame** will increase decoding delay by one frame per thread, so clients which
           cannot provide future frames should not use it.

           Possible values:

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

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

           **frame**
               Decode more than one frame at once.

           Default value is **slice+frame**.

       **audio**___**service**___**type** _integer_ **(**_encoding,audio_**)**
           Set audio service type.

           Possible values:

           **ma**  Main Audio Service

           **ef**  Effects

           **vi**  Visually Impaired

           **hi**  Hearing Impaired

           **di**  Dialogue

           **co**  Commentary

           **em**  Emergency

           **vo**  Voice Over

           **ka**  Karaoke

       **request**___**sample**___**fmt** _sample_fmt_ **(**_decoding,audio_**)**
           Set sample format audio decoders should prefer. Default value is "none".

       **pkt**___**timebase** _rational_ _number_
       **sub**___**charenc** _encoding_ **(**_decoding,subtitles_**)**
           Set the input subtitles character encoding.

       **field**___**order**  _field_order_ **(**_video_**)**
           Set/override the field order of the video.  Possible values:

           **progressive**
               Progressive video

           **tt**  Interlaced video, top field coded and displayed first

           **bb**  Interlaced video, bottom field coded and displayed first

           **tb**  Interlaced video, top coded first, bottom displayed first

           **bt**  Interlaced video, bottom coded first, top displayed first

       **skip**___**alpha** _bool_ **(**_decoding,video_**)**
           Set to 1 to disable processing alpha (transparency). This works like the **gray** flag in the
           **flags** option which skips chroma information instead of alpha. Default is 0.

       **codec**___**whitelist** _list_ **(**_input_**)**
           "," separated list of allowed decoders. By default all are allowed.

       **dump**___**separator** _string_ **(**_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 indentation:

                   ffprobe -dump_separator "
                                             "  -i ~/videos/matrixbench_mpeg2.mpg

       **max**___**pixels** _integer_ **(**_decoding/encoding,video_**)**
           Maximum number of pixels per image. This value can be used to avoid out of memory
           failures due to large images.

       **apply**___**cropping** _bool_ **(**_decoding,video_**)**
           Enable cropping if cropping parameters are multiples of the required alignment for the
           left and top parameters. If the alignment is not met the cropping will be partially
           applied to maintain alignment.  Default is 1 (enabled).  Note: The required alignment
           depends on if "AV_CODEC_FLAG_UNALIGNED" is set and the CPU. "AV_CODEC_FLAG_UNALIGNED"
           cannot be changed from the command line. Also hardware decoders will not apply left/top
           Cropping.

## DECODERS
       Decoders are configured elements in FFmpeg which allow the decoding of multimedia streams.

       When you configure your FFmpeg build, all the supported native decoders are enabled by
       default. Decoders requiring an external library must be enabled manually via the
       corresponding "--enable-lib" option. You can list all available decoders using the configure
       option "--list-decoders".

       You can disable all the decoders with the configure option "--disable-decoders" and
       selectively enable / disable single decoders with the options "--enable-decoder=_DECODER"_ /
       "--disable-decoder=_DECODER"_.

       The option "-decoders" of the ff* tools will display the list of enabled decoders.

## VIDEO DECODERS
       A description of some of the currently available video decoders follows.

### av1
       AOMedia Video 1 (AV1) decoder.

       _Options_

       **operating**___**point**
           Select an operating point of a scalable AV1 bitstream (0 - 31). Default is 0.

### rawvideo
       Raw video decoder.

       This decoder decodes rawvideo streams.

       _Options_

       **top** _top_field_first_
           Specify the assumed field type of the input video.

           **-1**  the video is assumed to be progressive (default)

           **0**   bottom-field-first is assumed

           **1**   top-field-first is assumed

### libdav1d
       dav1d AV1 decoder.

       libdav1d allows libavcodec to decode the AOMedia Video 1 (AV1) codec.  Requires the presence
       of the libdav1d headers and library during configuration.  You need to explicitly configure
       the build with "--enable-libdav1d".

       _Options_

       The following options are supported by the libdav1d wrapper.

### framethreads
           Set amount of frame threads to use during decoding. The default value is 0 (autodetect).

### tilethreads
           Set amount of tile threads to use during decoding. The default value is 0 (autodetect).

### filmgrain
           Apply film grain to the decoded video if present in the bitstream. Defaults to the
           internal default of the library.

### oppoint
           Select an operating point of a scalable AV1 bitstream (0 - 31). Defaults to the internal
           default of the library.

### alllayers
           Output all spatial layers of a scalable AV1 bitstream. The default value is false.

### libdavs2
       AVS2-P2/IEEE1857.4 video decoder wrapper.

       This decoder allows libavcodec to decode AVS2 streams with davs2 library.

### libuavs3d
       AVS3-P2/IEEE1857.10 video decoder.

       libuavs3d allows libavcodec to decode AVS3 streams.  Requires the presence of the libuavs3d
       headers and library during configuration.  You need to explicitly configure the build with
       "--enable-libuavs3d".

       _Options_

       The following option is supported by the libuavs3d wrapper.

       **frame**___**threads**
           Set amount of frame threads to use during decoding. The default value is 0 (autodetect).

## AUDIO DECODERS
       A description of some of the currently available audio decoders follows.

### ac3
       AC-3 audio decoder.

       This decoder implements part of ATSC A/52:2010 and ETSI TS 102 366, as well as the
       undocumented RealAudio 3 (a.k.a. dnet).

       _AC-3_ _Decoder_ _Options_

### -drc
           Dynamic Range Scale Factor. The factor to apply to dynamic range values from the AC-3
           stream. This factor is applied exponentially. The default value is 1.  There are 3
           notable scale factor ranges:

           **drc**___**scale** **==** **0**
               DRC disabled. Produces full range audio.

           **0** **<** **drc**___**scale** **<=** **1**
               DRC enabled.  Applies a fraction of the stream DRC value.  Audio reproduction is
               between full range and full compression.

           **drc**___**scale** **>** **1**
               DRC enabled. Applies drc_scale asymmetrically.  Loud sounds are fully compressed.
               Soft sounds are enhanced.

### flac
       FLAC audio decoder.

       This decoder aims to implement the complete FLAC specification from Xiph.

       _FLAC_ _Decoder_ _options_

### -use
           The lavc FLAC encoder used to produce buggy streams with high lpc values (like the
           default value). This option makes it possible to decode such streams correctly by using
           lavc's old buggy lpc logic for decoding.

### ffwavesynth
       Internal wave synthesizer.

       This decoder generates wave patterns according to predefined sequences. Its use is purely
       internal and the format of the data it accepts is not publicly documented.

### libcelt
       libcelt decoder wrapper.

       libcelt allows libavcodec to decode the Xiph CELT ultra-low delay audio codec.  Requires the
       presence of the libcelt headers and library during configuration.  You need to explicitly
       configure the build with "--enable-libcelt".

### libgsm
       libgsm decoder wrapper.

       libgsm allows libavcodec to decode the GSM full rate audio codec. Requires the presence of
       the libgsm headers and library during configuration. You need to explicitly configure the
       build with "--enable-libgsm".

       This decoder supports both the ordinary GSM and the Microsoft variant.

### libilbc
       libilbc decoder wrapper.

       libilbc allows libavcodec to decode the Internet Low Bitrate Codec (iLBC) audio codec.
       Requires the presence of the libilbc headers and library during configuration. You need to
       explicitly configure the build with "--enable-libilbc".

       _Options_

       The following option is supported by the libilbc wrapper.

### enhance
           Enable the enhancement of the decoded audio when set to 1. The default value is 0
           (disabled).

### libopencore-amrnb
       libopencore-amrnb decoder wrapper.

       libopencore-amrnb allows libavcodec to decode the Adaptive Multi-Rate Narrowband audio codec.
       Using it requires the presence of the libopencore-amrnb headers and library during
       configuration. You need to explicitly configure the build with "--enable-libopencore-amrnb".

       An FFmpeg native decoder for AMR-NB exists, so users can decode AMR-NB without this library.

### libopencore-amrwb
       libopencore-amrwb decoder wrapper.

       libopencore-amrwb allows libavcodec to decode the Adaptive Multi-Rate Wideband audio codec.
       Using it requires the presence of the libopencore-amrwb headers and library during
       configuration. You need to explicitly configure the build with "--enable-libopencore-amrwb".

       An FFmpeg native decoder for AMR-WB exists, so users can decode AMR-WB without this library.

### libopus
       libopus decoder wrapper.

       libopus allows libavcodec to decode the Opus Interactive Audio Codec.  Requires the presence
       of the libopus headers and library during configuration. You need to explicitly configure the
       build with "--enable-libopus".

       An FFmpeg native decoder for Opus exists, so users can decode Opus without this library.

## SUBTITLES DECODERS
### libaribb24
       ARIB STD-B24 caption decoder.

       Implements profiles A and C of the ARIB STD-B24 standard.

       _libaribb24_ _Decoder_ _Options_

### -aribb24-base-path
           Sets the base path for the libaribb24 library. This is utilized for reading of
           configuration files (for custom unicode conversions), and for dumping of non-text symbols
           as images under that location.

           Unset by default.

### -aribb24-skip-ruby-text
           Tells the decoder wrapper to skip text blocks that contain half-height ruby text.

           Enabled by default.

### dvbsub
       _Options_

       **compute**___**clut**
           **-1**  Compute clut if no matching CLUT is in the stream.

           **0**   Never compute CLUT

           **1**   Always compute CLUT and override the one provided in the stream.

       **dvb**___**substream**
           Selects the dvb substream, or all substreams if -1 which is default.

### dvdsub
       This codec decodes the bitmap subtitles used in DVDs; the same subtitles can also be found in
       VobSub file pairs and in some Matroska files.

       _Options_

### palette
           Specify the global palette used by the bitmaps. When stored in VobSub, the palette is
           normally specified in the index file; in Matroska, the palette is stored in the codec
           extra-data in the same format as in VobSub. In DVDs, the palette is stored in the IFO
           file, and therefore not available when reading from dumped VOB files.

           The format for this option is a string containing 16 24-bits hexadecimal numbers (without
           0x prefix) separated by commas, for example "0d00ee, ee450d, 101010, eaeaea, 0ce60b,
           ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1, 7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b".

       **ifo**___**palette**
           Specify the IFO file from which the global palette is obtained.  (experimental)

       **forced**___**subs**___**only**
           Only decode subtitle entries marked as forced. Some titles have forced and non-forced
           subtitles in the same track. Setting this flag to 1 will only keep the forced subtitles.
           Default value is 0.

### libzvbi-teletext
       Libzvbi allows libavcodec to decode DVB teletext pages and DVB teletext subtitles. Requires
       the presence of the libzvbi headers and library during configuration. You need to explicitly
       configure the build with "--enable-libzvbi".

       _Options_

       **txt**___**page**
           List of teletext page numbers to decode. Pages that do not match the specified list are
           dropped. You may use the special "*" string to match all pages, or "subtitle" to match
           all subtitle pages.  Default value is *.

       **txt**___**default**___**region**
           Set default character set used for decoding, a value between 0 and 87 (see ETS 300 706,
           Section 15, Table 32). Default value is -1, which does not override the libzvbi default.
           This option is needed for some legacy level 1.0 transmissions which cannot signal the
           proper charset.

       **txt**___**chop**___**top**
           Discards the top teletext line. Default value is 1.

       **txt**___**format**
           Specifies the format of the decoded subtitles.

           **bitmap**
               The default format, you should use this for teletext pages, because certain graphics
               and colors cannot be expressed in simple text or even ASS.

           **text**
               Simple text based output without formatting.

           **ass** Formatted ASS output, subtitle pages and teletext pages are returned in different
               styles, subtitle pages are stripped down to text, but an effort is made to keep the
               text alignment and the formatting.

       **txt**___**left**
           X offset of generated bitmaps, default is 0.

       **txt**___**top**
           Y offset of generated bitmaps, default is 0.

       **txt**___**chop**___**spaces**
           Chops leading and trailing spaces and removes empty lines from the generated text. This
           option is useful for teletext based subtitles where empty spaces may be present at the
           start or at the end of the lines or empty lines may be present between the subtitle lines
           because of double-sized teletext characters.  Default value is 1.

       **txt**___**duration**
           Sets the display duration of the decoded teletext pages or subtitles in milliseconds.
           Default value is -1 which means infinity or until the next subtitle event comes.

       **txt**___**transparent**
           Force transparent background of the generated teletext bitmaps. Default value is 0 which
           means an opaque background.

       **txt**___**opacity**
           Sets the opacity (0-255) of the teletext background. If **txt**___**transparent** is not set, it
           only affects characters between a start box and an end box, typically subtitles. Default
           value is 0 if **txt**___**transparent** is set, 255 otherwise.

## ENCODERS
       Encoders are configured elements in FFmpeg which allow the encoding of multimedia streams.

       When you configure your FFmpeg build, all the supported native encoders are enabled by
       default. Encoders requiring an external library must be enabled manually via the
       corresponding "--enable-lib" option. You can list all available encoders using the configure
       option "--list-encoders".

       You can disable all the encoders with the configure option "--disable-encoders" and
       selectively enable / disable single encoders with the options "--enable-encoder=_ENCODER"_ /
       "--disable-encoder=_ENCODER"_.

       The option "-encoders" of the ff* tools will display the list of enabled encoders.

## AUDIO ENCODERS
       A description of some of the currently available audio encoders follows.

### aac
       Advanced Audio Coding (AAC) encoder.

       This encoder is the default AAC encoder, natively implemented into FFmpeg.

       _Options_

       **b**   Set bit rate in bits/s. Setting this automatically activates constant bit rate (CBR)
           mode. If this option is unspecified it is set to 128kbps.

       **q**   Set quality for variable bit rate (VBR) mode. This option is valid only using the **ffmpeg**
           command-line tool. For library interface users, use **global**___**quality**.

### cutoff
           Set cutoff frequency. If unspecified will allow the encoder to dynamically adjust the
           cutoff to improve clarity on low bitrates.

       **aac**___**coder**
           Set AAC encoder coding method. Possible values:

           **twoloop**
               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.  Will tune itself based on whether
               **aac**___**is**, **aac**___**ms** and **aac**___**pns** are enabled.

           **anmr**
               Average noise to mask ratio (ANMR) trellis-based solution.

               This is an experimental coder which currently produces a lower quality, is more
               unstable and is slower than the default twoloop coder but has potential.  Currently
               has no support for the **aac**___**is** or **aac**___**pns** options.  Not currently recommended.

           **fast**
               Constant quantizer method.

               Uses a cheaper version of twoloop algorithm that doesn't try to do as many clever
               adjustments. Worse with low bitrates (less than 64kbps), but is better and much
               faster at higher bitrates.  This is the default choice for a coder

       **aac**___**ms**
           Sets mid/side coding mode. The default value of "auto" will automatically use M/S with
           bands which will benefit from such coding. Can be forced for all bands using the value
           "enable", which is mainly useful for debugging or disabled using "disable".

       **aac**___**is**
           Sets intensity stereo coding tool usage. By default, it's enabled and will automatically
           toggle IS for similar pairs of stereo bands if it's beneficial.  Can be disabled for
           debugging by setting the value to "disable".

       **aac**___**pns**
           Uses perceptual noise substitution to replace low entropy high frequency bands with
           imperceptible white noise during the decoding process. By default, it's enabled, but can
           be disabled for debugging purposes by using "disable".

       **aac**___**tns**
           Enables the use of a multitap FIR filter which spans through the high frequency bands to
           hide quantization noise during the encoding process and is reverted by the decoder. As
           well as decreasing unpleasant artifacts in the high range this also reduces the entropy
           in the high bands and allows for more bits to be used by the mid-low bands. By default
           it's enabled but can be disabled for debugging by setting the option to "disable".

       **aac**___**ltp**
           Enables the use of the long term prediction extension which increases coding efficiency
           in very low bandwidth situations such as encoding of voice or solo piano music by
           extending constant harmonic peaks in bands throughout frames. This option is implied by
           profile:a aac_low and is incompatible with aac_pred. Use in conjunction with **-ar** to
           decrease the samplerate.

       **aac**___**pred**
           Enables the use of a more traditional style of prediction where the spectral coefficients
           transmitted are replaced by the difference of the current coefficients minus the previous
           "predicted" coefficients. In theory and sometimes in practice this can improve quality
           for low to mid bitrate audio.  This option implies the aac_main profile and is
           incompatible with aac_ltp.

### profile
           Sets the encoding profile, possible values:

           **aac**___**low**
               The default, AAC "Low-complexity" profile. Is the most compatible and produces decent
               quality.

           **mpeg2**___**aac**___**low**
               Equivalent to "-profile:a aac_low -aac_pns 0". PNS was introduced with the MPEG4
               specifications.

           **aac**___**ltp**
               Long term prediction profile, is enabled by and will enable the **aac**___**ltp** option.
               Introduced in MPEG4.

           **aac**___**main**
               Main-type prediction profile, is enabled by and will enable the **aac**___**pred** option.
               Introduced in MPEG2.

           If this option is unspecified it is set to **aac**___**low**.

   **ac3** **and** **ac3**___**fixed**
       AC-3 audio encoders.

       These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366, as well as the
       undocumented RealAudio 3 (a.k.a. dnet).

       The _ac3_ encoder uses floating-point math, while the _ac3_fixed_ encoder only uses fixed-point
       integer math. This does not mean that one is always faster, just that one or the other may be
       better suited to a particular system. The _ac3_fixed_ encoder is not the default codec for any
       of the output formats, so it must be specified explicitly using the option "-acodec
       ac3_fixed" in order to use it.

       _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 do directly affect or
       influence the decoding and playback of the resulting bitstream, while others are just for
       informational purposes. A few of the options will add bits to the output stream that could
       otherwise be used for audio data, and will thus affect the quality of the output. Those will
       be indicated accordingly with a note in the option list below.

       These parameters are described in detail in several publicly-available documents.

       *<<**<http://www.atsc.org/cms/standards/a>**___**52-2010.pdf**>>
       *<<**<http://www.atsc.org/cms/standards/a>**___**54a**___**with**___**corr**___**1.pdf**>>
       *<<**<http://www.dolby.com/uploadedFiles/zz>-**___**Shared**___**Assets/English**___**PDFs/Professional/18**___**Metadata.Guide.pdf**>>
       *<<**<http://www.dolby.com/uploadedFiles/zz>-**___**Shared**___**Assets/English**___**PDFs/Professional/46**___**DDEncodingGuidelines.pdf**>>

       Metadata Control Options

### -per
           Allow Per-Frame Metadata. Specifies if the encoder should check for changing metadata for
           each frame.

           **0**   The metadata values set at initialization will be used for every frame in the stream.
               (default)

           **1**   Metadata values can be changed before encoding each frame.

       Downmix Levels

### -center
           Center Mix Level. The amount of gain the decoder should apply to the center channel when
           downmixing to stereo. This field will only be written to the bitstream if a center
           channel is present. The value is specified as a scale factor. There are 3 valid values:

           **0.707**
               Apply -3dB gain

           **0.595**
               Apply -4.5dB gain (default)

           **0.500**
               Apply -6dB gain

### -surround
           Surround Mix Level. The amount of gain the decoder should apply to the surround
           channel(s) when downmixing to stereo. This field will only be written to the bitstream if
           one or more surround channels are present. The value is specified as a scale factor.
           There are 3 valid values:

           **0.707**
               Apply -3dB gain

           **0.500**
               Apply -6dB gain (default)

           **0.000**
               Silence Surround Channel(s)

       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.

### -mixing
           Mixing Level. Specifies peak sound pressure level (SPL) in the production environment
           when the mix was mastered. Valid values are 80 to 111, or -1 for unknown or not
           indicated. The default value is -1, but that value cannot be used if the Audio Production
           Information is written to the bitstream. Therefore, if the "room_type" option is not the
           default value, the "mixing_level" option must not be -1.

### -room
           Room Type. Describes the equalization used during the final mixing session at the studio
           or on the dubbing stage. A large room is a dubbing stage with the industry standard
           X-curve equalization; a small room has flat equalization.  This field will not be written
           to the bitstream if both the "mixing_level" option and the "room_type" option have the
           default values.

           **0**
           **notindicated**
               Not Indicated (default)

           **1**
           **large**
               Large Room

           **2**
           **small**
               Small Room

       Other Metadata Options

### -copyright
           Copyright Indicator. Specifies whether a copyright exists for this audio.

           **0**
           **off** No Copyright Exists (default)

           **1**
           **on**  Copyright Exists

### -dialnorm
           Dialogue Normalization. Indicates how far the average dialogue level of the program is
           below digital 100% full scale (0 dBFS). This parameter determines a level shift during
           audio reproduction that sets the average volume of the dialogue to a preset level. The
           goal is to match volume level between program sources. A value of -31dB will result in no
           volume level change, relative to the source volume, during audio reproduction. Valid
           values are whole numbers in the range -31 to -1, with -31 being the default.

### -dsur
           Dolby Surround Mode. Specifies whether the stereo signal uses Dolby Surround (Pro Logic).
           This field will only be written to the bitstream if the audio stream is stereo. Using
           this option does **NOT** mean the encoder will actually apply Dolby Surround processing.

           **0**
           **notindicated**
               Not Indicated (default)

           **1**
           **off** Not Dolby Surround Encoded

           **2**
           **on**  Dolby Surround Encoded

### -original
           Original Bit Stream Indicator. Specifies whether this audio is from the original source
           and not a copy.

           **0**
           **off** Not Original Source

           **1**
           **on**  Original Source (default)

       _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 written to the bitstream.  Default
       values are used for those that are written but have not been specified.  If the mixing levels
       are written, the decoder will use these values instead of the ones specified in the
       "center_mixlev" and "surround_mixlev" options if it supports the Alternate Bit Stream Syntax.

       Extended Bitstream Information - Part 1

### -dmix
           Preferred Stereo Downmix Mode. Allows the user to select either Lt/Rt (Dolby Surround) or
           Lo/Ro (normal stereo) as the preferred stereo downmix mode.

           **0**
           **notindicated**
               Not Indicated (default)

           **1**
           **ltrt**
               Lt/Rt Downmix Preferred

           **2**
           **loro**
               Lo/Ro Downmix Preferred

### -ltrt
           Lt/Rt Center Mix Level. The amount of gain the decoder should apply to the center channel
           when downmixing to stereo in Lt/Rt mode.

           **1.414**
               Apply +3dB gain

           **1.189**
               Apply +1.5dB gain

           **1.000**
               Apply 0dB gain

           **0.841**
               Apply -1.5dB gain

           **0.707**
               Apply -3.0dB gain

           **0.595**
               Apply -4.5dB gain (default)

           **0.500**
               Apply -6.0dB gain

           **0.000**
               Silence Center Channel

### -ltrt
           Lt/Rt Surround Mix Level. The amount of gain the decoder should apply to the surround
           channel(s) when downmixing to stereo in Lt/Rt mode.

           **0.841**
               Apply -1.5dB gain

           **0.707**
               Apply -3.0dB gain

           **0.595**
               Apply -4.5dB gain

           **0.500**
               Apply -6.0dB gain (default)

           **0.000**
               Silence Surround Channel(s)

### -loro
           Lo/Ro Center Mix Level. The amount of gain the decoder should apply to the center channel
           when downmixing to stereo in Lo/Ro mode.

           **1.414**
               Apply +3dB gain

           **1.189**
               Apply +1.5dB gain

           **1.000**
               Apply 0dB gain

           **0.841**
               Apply -1.5dB gain

           **0.707**
               Apply -3.0dB gain

           **0.595**
               Apply -4.5dB gain (default)

           **0.500**
               Apply -6.0dB gain

           **0.000**
               Silence Center Channel

### -loro
           Lo/Ro Surround Mix Level. The amount of gain the decoder should apply to the surround
           channel(s) when downmixing to stereo in Lo/Ro mode.

           **0.841**
               Apply -1.5dB gain

           **0.707**
               Apply -3.0dB gain

           **0.595**
               Apply -4.5dB gain

           **0.500**
               Apply -6.0dB gain (default)

           **0.000**
               Silence Surround Channel(s)

       Extended Bitstream Information - Part 2

### -dsurex
           Dolby Surround EX Mode. Indicates whether the stream uses Dolby Surround EX (7.1 matrixed
           to 5.1). Using this option does **NOT** mean the encoder will actually apply Dolby Surround
           EX processing.

           **0**
           **notindicated**
               Not Indicated (default)

           **1**
           **on**  Dolby Surround EX Off

           **2**
           **off** Dolby Surround EX On

### -dheadphone
           Dolby Headphone Mode. Indicates whether the stream uses Dolby Headphone encoding (multi-
           channel matrixed to 2.0 for use with headphones). Using this option does **NOT** mean the
           encoder will actually apply Dolby Headphone processing.

           **0**
           **notindicated**
               Not Indicated (default)

           **1**
           **on**  Dolby Headphone Off

           **2**
           **off** Dolby Headphone On

### -ad
           A/D Converter Type. Indicates whether the audio has passed through HDCD A/D conversion.

           **0**
           **standard**
               Standard A/D Converter (default)

           **1**
           **hdcd**
               HDCD A/D Converter

       _Other_ _AC-3_ _Encoding_ _Options_

### -stereo
           Stereo Rematrixing. Enables/Disables use of rematrixing for stereo input. This is an
           optional AC-3 feature that increases quality by selectively encoding the left/right
           channels as mid/side. This option is enabled by default, and it is highly recommended
           that it be left as enabled except for testing purposes.

       **cutoff** _frequency_
           Set lowpass cutoff frequency. If unspecified, the encoder selects a default determined by
           various other encoding parameters.

       _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.

### -channel
           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.

           **-1**
           **auto**
               Selected by Encoder (default)

           **0**
           **off** Disable Channel Coupling

           **1**
           **on**  Enable Channel Coupling

### -cpl
           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 _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.

           **-1**
           **auto**
               Selected by Encoder (default)

### flac
       FLAC (Free Lossless Audio Codec) Encoder

       _Options_

       The following options are supported by FFmpeg's flac encoder.

       **compression**___**level**
           Sets the compression level, which chooses defaults for many other options if they are not
           set explicitly. Valid values are from 0 to 12, 5 is the default.

       **frame**___**size**
           Sets the size of the frames in samples per channel.

       **lpc**___**coeff**___**precision**
           Sets the LPC coefficient precision, valid values are from 1 to 15, 15 is the default.

       **lpc**___**type**
           Sets the first stage LPC algorithm

           **none**
               LPC is not used

           **fixed**
               fixed LPC coefficients

           **levinson**
           **cholesky**
       **lpc**___**passes**
           Number of passes to use for Cholesky factorization during LPC analysis

       **min**___**partition**___**order**
           The minimum partition order

       **max**___**partition**___**order**
           The maximum partition order

       **prediction**___**order**___**method**
           **estimation**
           **2level**
           **4level**
           **8level**
           **search**
               Bruteforce search

           **log**
       **ch**___**mode**
           Channel mode

           **auto**
               The mode is chosen automatically for each frame

           **indep**
               Channels are independently coded

           **left**___**side**
           **right**___**side**
           **mid**___**side**
       **exact**___**rice**___**parameters**
           Chooses if rice parameters are calculated exactly or approximately.  if set to 1 then
           they are chosen exactly, which slows the code down slightly and improves compression
           slightly.

       **multi**___**dim**___**quant**
           Multi Dimensional Quantization. If set to 1 then a 2nd stage LPC algorithm is applied
           after the first stage to finetune the coefficients. This is quite slow and slightly
           improves compression.

### opus
       Opus encoder.

       This is a native FFmpeg encoder for the Opus format. Currently its in development and only
       implements the CELT part of the codec. Its quality is usually worse and at best is equal to
       the libopus encoder.

       _Options_

       **b**   Set bit rate in bits/s. If unspecified it uses the number of channels and the layout to
           make a good guess.

       **opus**___**delay**
           Sets the maximum delay in milliseconds. Lower delays than 20ms will very quickly decrease
           quality.

   **libfdk**___**aac**
       libfdk-aac AAC (Advanced Audio Coding) encoder wrapper.

       The libfdk-aac library is based on the Fraunhofer FDK AAC code from the Android project.

       Requires the presence of the libfdk-aac headers and library during configuration. You need to
       explicitly configure the build with "--enable-libfdk-aac". The library is also incompatible
       with GPL, so if you allow the use of GPL, you should configure with "--enable-gpl
       --enable-nonfree --enable-libfdk-aac".

       This encoder has support for the AAC-HE profiles.

       VBR encoding, enabled through the **vbr** or **flags** **+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
       <**<http://sourceforge.net/p/opencore-amr/fdk-aac/>**>.

       _Options_

       The following options are mapped on the shared FFmpeg codec options.

       **b**   Set bit rate in bits/s. If the bitrate is not explicitly specified, it is automatically
           set to a suitable value depending on the selected profile.

           In case VBR mode is enabled the option is ignored.

       **ar**  Set audio sampling rate (in Hz).

### channels
           Set the number of audio channels.

### flags +qscale
           Enable fixed quality, VBR (Variable Bit Rate) mode.  Note that VBR is implicitly enabled
           when the **vbr** value is positive.

### cutoff
           Set cutoff frequency. If not specified (or explicitly set to 0) it will use a value
           automatically computed by the library. Default value is 0.

### profile
           Set audio profile.

           The following profiles are recognized:

           **aac**___**low**
               Low Complexity AAC (LC)

           **aac**___**he**
               High Efficiency AAC (HE-AAC)

           **aac**___**he**___**v2**
               High Efficiency AAC version 2 (HE-AACv2)

           **aac**___**ld**
               Low Delay AAC (LD)

           **aac**___**eld**
               Enhanced Low Delay AAC (ELD)

           If not specified it is set to **aac**___**low**.

       The following are private options of the libfdk_aac encoder.

### afterburner
           Enable afterburner feature if set to 1, disabled if set to 0. This improves the quality
           but also the required processing power.

           Default value is 1.

       **eld**___**sbr**
           Enable SBR (Spectral Band Replication) for ELD if set to 1, disabled if set to 0.

           Default value is 0.

       **eld**___**v2**
           Enable ELDv2 (LD-MPS extension for ELD stereo signals) for ELDv2 if set to 1, disabled if
           set to 0.

           Note that option is available when fdk-aac version
           (AACENCODER_LIB_VL0.AACENCODER_LIB_VL1.AACENCODER_LIB_VL2) > (4.0.0).

           Default value is 0.

### signaling
           Set SBR/PS signaling style.

           It can assume one of the following values:

           **default**
               choose signaling implicitly (explicit hierarchical by default, implicit if global
               header is disabled)

           **implicit**
               implicit backwards compatible signaling

           **explicit**___**sbr**
               explicit SBR, implicit PS signaling

           **explicit**___**hierarchical**
               explicit hierarchical signaling

           Default value is **default**.

### latm
           Output LATM/LOAS encapsulated data if set to 1, disabled if set to 0.

           Default value is 0.

       **header**___**period**
           Set StreamMuxConfig and PCE repetition period (in frames) for sending in-band
           configuration buffers within LATM/LOAS transport layer.

           Must be a 16-bits non-negative integer.

           Default value is 0.

       **vbr** Set VBR mode, from 1 to 5. 1 is lowest quality (though still pretty good) and 5 is
           highest quality. A value of 0 will disable VBR, and CBR (Constant Bit Rate) is enabled.

           Currently only the **aac**___**low** profile supports VBR encoding.

           VBR modes 1-5 correspond to roughly the following average bit rates:

           **1**   32 kbps/channel

           **2**   40 kbps/channel

           **3**   48-56 kbps/channel

           **4**   64 kbps/channel

           **5**   about 80-96 kbps/channel

           Default value is 0.

       _Examples_

       •   Use **ffmpeg** to convert an audio file to VBR AAC in an M4A (MP4) container:

                   ffmpeg -i input.wav -codec:a libfdk_aac -vbr 3 output.m4a

       •   Use **ffmpeg** to convert an audio file to CBR 64k kbps AAC, using the High-Efficiency AAC
           profile:

                   ffmpeg -i input.wav -c:a libfdk_aac -profile:a aac_he -b:a 64k output.m4a

### libmp3lame
       LAME (Lame Ain't an MP3 Encoder) MP3 encoder wrapper.

       Requires the presence of the libmp3lame headers and library during configuration. You need to
       explicitly configure the build with "--enable-libmp3lame".

       See **libshine** for a fixed-point MP3 encoder, although with a lower quality.

       _Options_

       The following options are supported by the libmp3lame wrapper. The **lame**-equivalent of the
       options are listed in parentheses.

       **b** **(**_-b_**)**
           Set bitrate expressed in bits/s for CBR or ABR. LAME "bitrate" is expressed in
           kilobits/s.

       **q** **(**_-V_**)**
           Set constant quality setting for VBR. This option is valid only using the **ffmpeg** command-
           line tool. For library interface users, use **global**___**quality**.

       **compression**___**level** **(**_-q_**)**
           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.

       **cutoff** **(**_--lowpass_**)**
           Set lowpass cutoff frequency. If unspecified, the encoder dynamically adjusts the cutoff.

### reservoir
           Enable use of bit reservoir when set to 1. Default value is 1. LAME has this enabled by
           default, but can be overridden by use **--nores** option.

       **joint**___**stereo** **(**_-m_ _j_**)**
           Enable the encoder to use (on a frame by frame basis) either L/R stereo or mid/side
           stereo. Default value is 1.

       **abr** **(**_--abr_**)**
           Enable the encoder to use ABR when set to 1. The **lame** **--abr** sets the target bitrate,
           while this options only tells FFmpeg to use ABR still relies on **b** to set bitrate.

### libopencore-amrnb
       OpenCORE Adaptive Multi-Rate Narrowband encoder.

       Requires the presence of the libopencore-amrnb headers and library during configuration. You
       need to explicitly configure the build with "--enable-libopencore-amrnb --enable-version3".

       This is a mono-only encoder. Officially it only supports 8000Hz sample rate, but you can
       override it by setting **strict** to **unofficial** or lower.

       _Options_

       **b**   Set bitrate in bits per second. Only the following bitrates are supported, otherwise
           libavcodec will round to the nearest valid bitrate.

           **4750**
           **5150**
           **5900**
           **6700**
           **7400**
           **7950**
           **10200**
           **12200**
       **dtx** Allow discontinuous transmission (generate comfort noise) when set to 1. The default
           value is 0 (disabled).

### libopus
       libopus Opus Interactive Audio Codec encoder wrapper.

       Requires the presence of the libopus headers and library during configuration. You need to
       explicitly configure the build with "--enable-libopus".

       _Option_ _Mapping_

       Most libopus options are modelled after the **opusenc** utility from opus-tools. The following is
       an option mapping chart describing options supported by the libopus wrapper, and their
       **opusenc**-equivalent in parentheses.

       **b** **(**_bitrate_**)**
           Set the bit rate in bits/s.  FFmpeg's **b** option is expressed in bits/s, while **opusenc**'s
           **bitrate** in kilobits/s.

       **vbr** **(**_vbr_**,** _hard-cbr_**,** **and** _cvbr_**)**
           Set VBR mode. The FFmpeg **vbr** option has the following valid arguments, with the **opusenc**
           equivalent options in parentheses:

           **off** **(**_hard-cbr_**)**
               Use constant bit rate encoding.

           **on** **(**_vbr_**)**
               Use variable bit rate encoding (the default).

           **constrained** **(**_cvbr_**)**
               Use constrained variable bit rate encoding.

       **compression**___**level** **(**_comp_**)**
           Set encoding algorithm complexity. Valid options are integers in the 0-10 range. 0 gives
           the fastest encodes but lower quality, while 10 gives the highest quality but slowest
           encoding. The default is 10.

       **frame**___**duration** **(**_framesize_**)**
           Set maximum frame size, or duration of a frame in milliseconds. The argument must be
           exactly the following: 2.5, 5, 10, 20, 40, 60. Smaller frame sizes achieve lower latency
           but less quality at a given bitrate.  Sizes greater than 20ms are only interesting at
           fairly low bitrates.  The default is 20ms.

       **packet**___**loss** **(**_expect-loss_**)**
           Set expected packet loss percentage. The default is 0.

       **fec** **(**_n/a_**)**
           Enable inband forward error correction. **packet**___**loss** must be non-zero to take advantage -
           frequency of FEC 'side-data' is proportional to expected packet loss.  Default is
           disabled.

### application (N.A.)
           Set intended application type. Valid options are listed below:

           **voip**
               Favor improved speech intelligibility.

           **audio**
               Favor faithfulness to the input (the default).

           **lowdelay**
               Restrict to only the lowest delay modes.

### cutoff (N.A.)
           Set cutoff bandwidth in Hz. The argument must be exactly one of the following: 4000,
           6000, 8000, 12000, or 20000, corresponding to narrowband, mediumband, wideband, super
           wideband, and fullband respectively. The default is 0 (cutoff disabled).

       **mapping**___**family** **(**_mapping_family_**)**
           Set channel mapping family to be used by the encoder. The default value of -1 uses
           mapping family 0 for mono and stereo inputs, and mapping family 1 otherwise. The default
           also disables the surround masking and LFE bandwidth optimzations in libopus, and
           requires that the input contains 8 channels or fewer.

           Other values include 0 for mono and stereo, 1 for surround sound with masking and LFE
           bandwidth optimizations, and 255 for independent streams with an unspecified channel
           layout.

       **apply**___**phase**___**inv** **(N.A.)** **(requires** **libopus** **>=** **1.2)**
           If set to 0, disables the use of phase inversion for intensity stereo, improving the
           quality of mono downmixes, but slightly reducing normal stereo quality. The default is 1
           (phase inversion enabled).

### libshine
       Shine Fixed-Point MP3 encoder wrapper.

       Shine is a fixed-point MP3 encoder. It has a far better performance on platforms without an
       FPU, e.g. armel CPUs, and some phones and tablets.  However, as it is more targeted on
       performance than quality, it is not on par with LAME and other production-grade encoders
       quality-wise. Also, according to the project's homepage, this encoder may not be free of bugs
       as the code was written a long time ago and the project was dead for at least 5 years.

       This encoder only supports stereo and mono input. This is also CBR-only.

       The original project (last updated in early 2007) is at
       <**<http://sourceforge.net/projects/libshine-fxp/>**>. We only support the updated fork by the
       Savonet/Liquidsoap project at <**<https://github.com/savonet/shine>**>.

       Requires the presence of the libshine headers and library during configuration. You need to
       explicitly configure the build with "--enable-libshine".

       See also **libmp3lame**.

       _Options_

       The following options are supported by the libshine wrapper. The **shineenc**-equivalent of the
       options are listed in parentheses.

       **b** **(**_-b_**)**
           Set bitrate expressed in bits/s for CBR. **shineenc** **-b** option is expressed in kilobits/s.

### libtwolame
       TwoLAME MP2 encoder wrapper.

       Requires the presence of the libtwolame headers and library during configuration. You need to
       explicitly configure the build with "--enable-libtwolame".

       _Options_

       The following options are supported by the libtwolame wrapper. The **twolame**-equivalent options
       follow the FFmpeg ones and are in parentheses.

       **b** **(**_-b_**)**
           Set bitrate expressed in bits/s for CBR. **twolame** **b** option is expressed in kilobits/s.
           Default value is 128k.

       **q** **(**_-V_**)**
           Set quality for experimental VBR support. Maximum value range is 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 **ffmpeg** command-line tool. For library interface users, use
           **global**___**quality**.

       **mode** **(**_--mode_**)**
           Set the mode of the resulting audio. Possible values:

           **auto**
               Choose mode automatically based on the input. This is the default.

           **stereo**
               Stereo

           **joint**___**stereo**
               Joint stereo

           **dual**___**channel**
               Dual channel

           **mono**
               Mono

       **psymodel** **(**_--psyc-mode_**)**
           Set psychoacoustic model to use in encoding. The argument must be an integer between -1
           and 4, inclusive. The higher the value, the better the quality. The default value is 3.

       **energy**___**levels** **(**_--energy_**)**
           Enable energy levels extensions when set to 1. The default value is 0 (disabled).

       **error**___**protection** **(**_--protect_**)**
           Enable CRC error protection when set to 1. The default value is 0 (disabled).

       **copyright** **(**_--copyright_**)**
           Set MPEG audio copyright flag when set to 1. The default value is 0 (disabled).

       **original** **(**_--original_**)**
           Set MPEG audio original flag when set to 1. The default value is 0 (disabled).

### libvo-amrwbenc
       VisualOn Adaptive Multi-Rate Wideband encoder.

       Requires the presence of the libvo-amrwbenc headers and library during configuration. You
       need to explicitly configure the build with "--enable-libvo-amrwbenc --enable-version3".

       This is a mono-only encoder. Officially it only supports 16000Hz sample rate, but you can
       override it by setting **strict** to **unofficial** or lower.

       _Options_

       **b**   Set bitrate in bits/s. Only the following bitrates are supported, otherwise libavcodec
           will round to the nearest valid bitrate.

           **6600**
           **8850**
           **12650**
           **14250**
           **15850**
           **18250**
           **19850**
           **23050**
           **23850**
       **dtx** Allow discontinuous transmission (generate comfort noise) when set to 1. The default
           value is 0 (disabled).

### libvorbis
       libvorbis encoder wrapper.

       Requires the presence of the libvorbisenc headers and library during configuration. You need
       to explicitly configure the build with "--enable-libvorbis".

       _Options_

       The following options are supported by the libvorbis wrapper. The **oggenc**-equivalent of the
       options are listed in parentheses.

       To get a more accurate and extensive documentation of the libvorbis options, consult the
       libvorbisenc's and **oggenc**'s documentations.  See <**<http://xiph.org/vorbis/>**>,
       <**<http://wiki.xiph.org/Vorbis-tools>**>, and [**oggenc**(1)](https://www.chedong.com/phpMan.php/man/oggenc/1/markdown).

       **b** **(**_-b_**)**
           Set bitrate expressed in bits/s for ABR. **oggenc** **-b** is expressed in kilobits/s.

       **q** **(**_-q_**)**
           Set constant quality setting for VBR. The value should be a float number in the range of
           -1.0 to 10.0. The higher the value, the better the quality. The default value is **3.0**.

           This option is valid only using the **ffmpeg** command-line tool.  For library interface
           users, use **global**___**quality**.

       **cutoff** **(**_--advanced-encode-option_ _lowpass_frequency=N_**)**
           Set cutoff bandwidth in Hz, a value of 0 disables cutoff. **oggenc**'s related option is
           expressed in kHz. The default value is **0** (cutoff disabled).

       **minrate** **(**_-m_**)**
           Set minimum bitrate expressed in bits/s. **oggenc** **-m** is expressed in kilobits/s.

       **maxrate** **(**_-M_**)**
           Set maximum bitrate expressed in bits/s. **oggenc** **-M** is expressed in kilobits/s. This only
           has effect on ABR mode.

       **iblock** **(**_--advanced-encode-option_ _impulse_noisetune=N_**)**
           Set noise floor bias for impulse blocks. The value is a float number from -15.0 to 0.0. A
           negative bias instructs the encoder to pay special attention to the crispness of
           transients in the encoded audio. The tradeoff for better transient response is a higher
           bitrate.

### mjpeg
       Motion JPEG encoder.

       _Options_

### huffman
           Set the huffman encoding strategy. Possible values:

           **default**
               Use the default huffman tables. This is the default strategy.

           **optimal**
               Compute and use optimal huffman tables.

### wavpack
       WavPack lossless audio encoder.

       _Options_

       The equivalent options for **wavpack** command line utility are listed in parentheses.

       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 **the**
       **Codec** **Options** **chapter**.

       **frame**___**size** **(**_--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 _libavcodec/wavpackenc.c_.

       **compression**___**level** **(**_-f_**,** _-h_**,** _-hh_**,** **and** _-x_**)**

       Private options

       **joint**___**stereo** **(**_-j_**)**
           Set whether to enable joint stereo. Valid values are:

           **on** **(**_1_**)**
               Force mid/side audio encoding.

           **off** **(**_0_**)**
               Force left/right audio encoding.

           **auto**
               Let the encoder decide automatically.

       **optimize**___**mono**
           Set whether to enable optimization for mono. This option is only effective for non-mono
           streams. Available values:

           **on**  enabled

           **off** disabled

## VIDEO ENCODERS
       A description of some of the currently available video encoders follows.

   **GIF**
       GIF image/animation encoder.

       _Options_

       **gifflags** _integer_
           Sets the flags used for GIF encoding.

           **offsetting**
               Enables picture offsetting.

               Default is enabled.

           **transdiff**
               Enables transparency detection between frames.

               Default is enabled.

       **gifimage** _integer_
           Enables encoding one full GIF image per frame, rather than an animated GIF.

           Default value is **0**.

       **global**___**palette** _integer_
           Writes a palette to the global GIF header where feasible.

           If disabled, every frame will always have a palette written, even if there is a global
           palette supplied.

           Default value is **1**.

### Hap
       Vidvox Hap video encoder.

       _Options_

       **format** _integer_
           Specifies the Hap format to encode.

           **hap**
           **hap**___**alpha**
           **hap**___**q**

           Default value is **hap**.

       **chunks** _integer_
           Specifies the number of chunks to split frames into, between 1 and 64. This permits
           multithreaded decoding of large frames, potentially at the cost of data-rate. The encoder
           may modify this value to divide frames evenly.

           Default value is _1_.

       **compressor** _integer_
           Specifies the second-stage compressor to use. If set to **none**, **chunks** will be limited to
           1, as chunked uncompressed frames offer no benefit.

           **none**
           **snappy**

           Default value is **snappy**.

### jpeg2000
       The native jpeg 2000 encoder is lossy by default, the "-q:v" option can be used to set the
       encoding quality. Lossless encoding can be selected with "-pred 1".

       _Options_

       **format** _integer_
           Can be set to either "j2k" or "jp2" (the default) that makes it possible to store non-rgb
           pix_fmts.

       **tile**___**width** _integer_
           Sets tile width. Range is 1 to 1073741824. Default is 256.

       **tile**___**height** _integer_
           Sets tile height. Range is 1 to 1073741824. Default is 256.

       **pred** _integer_
           Allows setting the discrete wavelet transform (DWT) type

           **dwt97int** **(Lossy)**
           **dwt53** **(Lossless)**

           Default is "dwt97int"

       **sop** _boolean_
           Enable this to add SOP marker at the start of each packet. Disabled by default.

       **eph** _boolean_
           Enable this to add EPH marker at the end of each packet header. Disabled by default.

       **prog** _integer_
           Sets the progression order to be used by the encoder.  Possible values are:

           **lrcp**
           **rlcp**
           **rpcl**
           **pcrl**
           **cprl**

           Set to "lrcp" by default.

       **layer**___**rates** _string_
           By default, when this option is not used, compression is done using the quality metric.
           This option allows for compression using compression ratio. The compression ratio for
           each level could be specified. The compression ratio of a layer "l" species the what
           ratio of total file size is contained in the first "l" layers.

           Example usage:

                   ffmpeg -i input.bmp -c:v jpeg2000 -layer_rates "100,10,1" output.j2k

           This would compress the image to contain 3 layers, where the data contained in the first
           layer would be compressed by 1000 times, compressed by 100 in the first two layers, and
           shall contain all data while using all 3 layers.

### librav1e
       rav1e AV1 encoder wrapper.

       Requires the presence of the rav1e headers and library during configuration.  You need to
       explicitly configure the build with "--enable-librav1e".

       _Options_

### qmax
           Sets the maximum quantizer to use when using bitrate mode.

### qmin
           Sets the minimum quantizer to use when using bitrate mode.

       **qp**  Uses quantizer mode to encode at the given quantizer (0-255).

### speed
           Selects the speed preset (0-10) to encode with.

### tiles
           Selects how many tiles to encode with.

### tile-rows
           Selects how many rows of tiles to encode with.

### tile-columns
           Selects how many columns of tiles to encode with.

### rav1e-params
           Set rav1e options using a list of _key_=_value_ pairs separated by ":". See **rav1e** **--help** for
           a list of options.

           For example to specify librav1e encoding options with **-rav1e-params**:

                   ffmpeg -i input -c:v librav1e -b:v 500K -rav1e-params speed=5:low_latency=true output.mp4

### libaom-av1
       libaom AV1 encoder wrapper.

       Requires the presence of the libaom headers and library during configuration.  You need to
       explicitly configure the build with "--enable-libaom".

       _Options_

       The wrapper supports the following standard libavcodec options:

       **b**   Set bitrate target in bits/second.  By default this will use variable-bitrate mode.  If
           **maxrate** and **minrate** are also set to the same value then it will use constant-bitrate
           mode, otherwise if **crf** is set as well then it will use constrained-quality mode.

       **g** **keyint**___**min**
           Set key frame placement.  The GOP size sets the maximum distance between key frames; if
           zero the output stream will be intra-only.  The minimum distance is ignored unless it is
           the same as the GOP size, in which case key frames will always appear at a fixed
           interval.  Not set by default, so without this option the library has completely free
           choice about where to place key frames.

### qmin qmax
           Set minimum/maximum quantisation values.  Valid range is from 0 to 63 (warning: this does
           not match the quantiser values actually used by AV1 - divide by four to map real
           quantiser values to this range).  Defaults to min/max (no constraint).

       **minrate** **maxrate** **bufsize** **rc**___**init**___**occupancy**
           Set rate control buffering parameters.  Not used if not set - defaults to unconstrained
           variable bitrate.

### threads
           Set the number of threads to use while encoding.  This may require the **tiles** or **row-mt**
           options to also be set to actually use the specified number of threads fully. Defaults to
           the number of hardware threads supported by the host machine.

### profile
           Set the encoding profile.  Defaults to using the profile which matches the bit depth and
           chroma subsampling of the input.

       The wrapper also has some specific options:

### cpu-used
           Set the quality/encoding speed tradeoff.  Valid range is from 0 to 8, higher numbers
           indicating greater speed and lower quality.  The default value is 1, which will be slow
           and high quality.

### auto-alt-ref
           Enable use of alternate reference frames.  Defaults to the internal default of the
           library.

       **arnr-max-frames** **(**_frames_**)**
           Set altref noise reduction max frame count. Default is -1.

       **arnr-strength** **(**_strength_**)**
           Set altref noise reduction filter strength. Range is -1 to 6. Default is -1.

       **aq-mode** **(**_aq-mode_**)**
           Set adaptive quantization mode. Possible values:

           **none** **(**_0_**)**
               Disabled.

           **variance** **(**_1_**)**
               Variance-based.

           **complexity** **(**_2_**)**
               Complexity-based.

           **cyclic** **(**_3_**)**
               Cyclic refresh.

       **tune** **(**_tune_**)**
           Set the distortion metric the encoder is tuned with. Default is "psnr".

           **psnr** **(**_0_**)**
           **ssim** **(**_1_**)**
### lag-in-frames
           Set the maximum number of frames which the encoder may keep in flight at any one time for
           lookahead purposes.  Defaults to the internal default of the library.

### error-resilience
           Enable error resilience features:

           **default**
               Improve resilience against losses of whole frames.

           Not enabled by default.

       **crf** Set the quality/size tradeoff for constant-quality (no bitrate target) and constrained-
           quality (with maximum bitrate target) modes. Valid range is 0 to 63, higher numbers
           indicating lower quality and smaller output size.  Only used if set; by default only the
           bitrate target is used.

### static-thresh
           Set a change threshold on blocks below which they will be skipped by the encoder.
           Defined in arbitrary units as a nonnegative integer, defaulting to zero (no blocks are
           skipped).

### drop-threshold
           Set a threshold for dropping frames when close to rate control bounds.  Defined as a
           percentage of the target buffer - when the rate control buffer falls below this
           percentage, frames will be dropped until it has refilled above the threshold.  Defaults
           to zero (no frames are dropped).

       **denoise-noise-level** **(**_level_**)**
           Amount of noise to be removed for grain synthesis. Grain synthesis is disabled if this
           option is not set or set to 0.

       **denoise-block-size** **(**_pixels_**)**
           Block size used for denoising for grain synthesis. If not set, AV1 codec uses the default
           value of 32.

       **undershoot-pct** **(**_pct_**)**
           Set datarate undershoot (min) percentage of the target bitrate. Range is -1 to 100.
           Default is -1.

       **overshoot-pct** **(**_pct_**)**
           Set datarate overshoot (max) percentage of the target bitrate. Range is -1 to 1000.
           Default is -1.

       **minsection-pct** **(**_pct_**)**
           Minimum percentage variation of the GOP bitrate from the target bitrate. If minsection-
           pct is not set, the libaomenc wrapper computes it as follows: "(minrate * 100 /
           bitrate)".  Range is -1 to 100. Default is -1 (unset).

       **maxsection-pct** **(**_pct_**)**
           Maximum percentage variation of the GOP bitrate from the target bitrate. If maxsection-
           pct is not set, the libaomenc wrapper computes it as follows: "(maxrate * 100 /
           bitrate)".  Range is -1 to 5000. Default is -1 (unset).

       **frame-parallel** **(**_boolean_**)**
           Enable frame parallel decodability features. Default is true.

### tiles
           Set the number of tiles to encode the input video with, as columns x rows.  Larger
           numbers allow greater parallelism in both encoding and decoding, but may decrease coding
           efficiency.  Defaults to the minimum number of tiles required by the size of the input
           video (this is 1x1 (that is, a single tile) for sizes up to and including 4K).

### tile-columns tile-rows
           Set the number of tiles as log2 of the number of tile rows and columns.  Provided for
           compatibility with libvpx/VP9.

### row-mt (Requires libaom >= 1.0.0-759-g90a15f4f2)
           Enable row based multi-threading. Disabled by default.

       **enable-cdef** **(**_boolean_**)**
           Enable Constrained Directional Enhancement Filter. The libaom-av1 encoder enables CDEF by
           default.

       **enable-restoration** **(**_boolean_**)**
           Enable Loop Restoration Filter. Default is true for libaom-av1.

       **enable-global-motion** **(**_boolean_**)**
           Enable the use of global motion for block prediction. Default is true.

       **enable-intrabc** **(**_boolean_**)**
           Enable block copy mode for intra block prediction. This mode is useful for screen
           content. Default is true.

       **enable-rect-partitions** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable rectangular partitions. Default is true.

       **enable-1to4-partitions** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable 1:4/4:1 partitions. Default is true.

       **enable-ab-partitions** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable AB shape partitions. Default is true.

       **enable-angle-delta** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable angle delta intra prediction. Default is true.

       **enable-cfl-intra** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable chroma predicted from luma intra prediction. Default is true.

       **enable-filter-intra** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable filter intra predictor. Default is true.

       **enable-intra-edge-filter** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable intra edge filter. Default is true.

       **enable-smooth-intra** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable smooth intra prediction mode. Default is true.

       **enable-paeth-intra** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable paeth predictor in intra prediction. Default is true.

       **enable-palette** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable palette prediction mode. Default is true.

       **enable-flip-idtx** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable extended transform type, including FLIPADST_DCT, DCT_FLIPADST, FLIPADST_FLIPADST,
           ADST_FLIPADST, FLIPADST_ADST, IDTX, V_DCT, H_DCT, V_ADST, H_ADST, V_FLIPADST, H_FLIPADST.
           Default is true.

       **enable-tx64** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable 64-pt transform. Default is true.

       **reduced-tx-type-set** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Use reduced set of transform types. Default is false.

       **use-intra-dct-only** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Use DCT only for INTRA modes. Default is false.

       **use-inter-dct-only** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Use DCT only for INTER modes. Default is false.

       **use-intra-default-tx-only** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Use Default-transform only for INTRA modes. Default is false.

       **enable-ref-frame-mvs** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable temporal mv prediction. Default is true.

       **enable-reduced-reference-set** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Use reduced set of single and compound references. Default is false.

       **enable-obmc** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable obmc. Default is true.

       **enable-dual-filter** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable dual filter. Default is true.

       **enable-diff-wtd-comp** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable difference-weighted compound. Default is true.

       **enable-dist-wtd-comp** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable distance-weighted compound. Default is true.

       **enable-onesided-comp** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable one sided compound. Default is true.

       **enable-interinter-wedge** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable interinter wedge compound. Default is true.

       **enable-interintra-wedge** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable interintra wedge compound. Default is true.

       **enable-masked-comp** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable masked compound. Default is true.

       **enable-interintra-comp** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable interintra compound. Default is true.

       **enable-smooth-interintra** **(**_boolean_**)** **(Requires** **libaom** **>=** **v2.0.0)**
           Enable smooth interintra mode. Default is true.

### aom-params
           Set libaom options using a list of _key_=_value_ pairs separated by ":". For a list of
           supported options, see **aomenc** **--help** under the section "AV1 Specific Options".

           For example to specify libaom encoding options with **-aom-params**:

                   ffmpeg -i input -c:v libaom-av1 -b:v 500K -aom-params tune=psnr:enable-tpl-model=1 output.mp4

### libsvtav1
       SVT-AV1 encoder wrapper.

       Requires the presence of the SVT-AV1 headers and library during configuration.  You need to
       explicitly configure the build with "--enable-libsvtav1".

       _Options_

### profile
           Set the encoding profile.

### level
           Set the operating point level.

### tier
           Set the operating point tier.

       **rc**  Set the rate control mode to use.

           Possible modes:

           **cqp** Constant quantizer: use fixed values of qindex (dependent on the frame type)
               throughout the stream.  This mode is the default.

           **vbr** Variable bitrate: use a target bitrate for the whole stream.

           **cvbr**
               Constrained variable bitrate: use a target bitrate for each GOP.

### qmax
           Set the maximum quantizer to use when using a bitrate mode.

### qmin
           Set the minimum quantizer to use when using a bitrate mode.

       **qp**  Set the quantizer used in cqp rate control mode (0-63).

       **sc**___**detection**
           Enable scene change detection.

       **la**___**depth**
           Set number of frames to look ahead (0-120).

### preset
           Set the quality-speed tradeoff, in the range 0 to 8.  Higher values are faster but lower
           quality.  Defaults to 8 (highest speed).

       **tile**___**rows**
           Set log2 of the number of rows of tiles to use (0-6).

       **tile**___**columns**
           Set log2 of the number of columns of tiles to use (0-4).

### libkvazaar
       Kvazaar H.265/HEVC encoder.

       Requires the presence of the libkvazaar headers and library during configuration. You need to
       explicitly configure the build with **--enable-libkvazaar**.

       _Options_

       **b**   Set target video bitrate in bit/s and enable rate control.

### kvazaar-params
           Set kvazaar parameters as a list of _name_=_value_ pairs separated by commas (,). See kvazaar
           documentation for a list of options.

### libopenh264
       Cisco libopenh264 H.264/MPEG-4 AVC encoder wrapper.

       This encoder requires the presence of the libopenh264 headers and library during
       configuration. You need to explicitly configure the build with "--enable-libopenh264". The
       library is detected using **pkg-config**.

       For more information about the library see <**<http://www.openh264.org>**>.

       _Options_

       The following FFmpeg global options affect the configurations of the libopenh264 encoder.

       **b**   Set the bitrate (as a number of bits per second).

       **g**   Set the GOP size.

### maxrate
           Set the max bitrate (as a number of bits per second).

       **flags** **+global**___**header**
           Set global header in the bitstream.

### slices
           Set the number of slices, used in parallelized encoding. Default value is 0. This is only
           used when **slice**___**mode** is set to **fixed**.

       **slice**___**mode**
           Set slice mode. Can assume one of the following possible values:

           **fixed**
               a fixed number of slices

           **rowmb**
               one slice per row of macroblocks

           **auto**
               automatic number of slices according to number of threads

           **dyn** dynamic slicing

           Default value is **auto**.

### loopfilter
           Enable loop filter, if set to 1 (automatically enabled). To disable set a value of 0.

### profile
           Set profile restrictions. If set to the value of **main** enable CABAC (set the
           "SEncParamExt.iEntropyCodingModeFlag" flag to 1).

       **max**___**nal**___**size**
           Set maximum NAL size in bytes.

       **allow**___**skip**___**frames**
           Allow skipping frames to hit the target bitrate if set to 1.

### libtheora
       libtheora Theora encoder wrapper.

       Requires the presence of the libtheora headers and library during configuration. You need to
       explicitly configure the build with "--enable-libtheora".

       For more information about the libtheora project see <**<http://www.theora.org/>**>.

       _Options_

       The following global options are mapped to internal libtheora options which affect the
       quality and the bitrate of the encoded stream.

       **b**   Set the video bitrate in bit/s for CBR (Constant Bit Rate) mode.  In case VBR (Variable
           Bit Rate) mode is enabled this option is ignored.

### flags
           Used to enable constant quality mode (VBR) encoding through the **qscale** flag, and to
           enable the "pass1" and "pass2" modes.

       **g**   Set the GOP size.

       **global**___**quality**
           Set the global quality as an integer in lambda units.

           Only relevant when VBR mode is enabled with "flags +qscale". The value is converted to QP
           units by dividing it by "FF_QP2LAMBDA", clipped in the [0 - 10] range, and then
           multiplied by 6.3 to get a value in the native libtheora range [0-63]. A higher value
           corresponds to a higher quality.

       **q**   Enable VBR mode when set to a non-negative value, and set constant quality value as a
           double floating point value in QP units.

           The value is clipped in the [0-10] range, and then multiplied by 6.3 to get a value in
           the native libtheora range [0-63].

           This option is valid only using the **ffmpeg** command-line tool. For library interface
           users, use **global**___**quality**.

       _Examples_

       •   Set maximum constant quality (VBR) encoding with **ffmpeg**:

                   ffmpeg -i INPUT -codec:v libtheora -q:v 10 OUTPUT.ogg

       •   Use **ffmpeg** to convert a CBR 1000 kbps Theora video stream:

                   ffmpeg -i INPUT -codec:v libtheora -b:v 1000k OUTPUT.ogg

### libvpx
       VP8/VP9 format supported through libvpx.

       Requires the presence of the libvpx headers and library during configuration.  You need to
       explicitly configure the build with "--enable-libvpx".

       _Options_

       The following options are supported by the libvpx wrapper. The **vpxenc**-equivalent options or
       values are listed in parentheses for easy migration.

       To reduce the duplication of documentation, only the private options and some others
       requiring special attention are documented here. For the documentation of the undocumented
       generic options, see **the** **Codec** **Options** **chapter**.

       To get more documentation of the libvpx options, invoke the command **ffmpeg** **-h** **encoder=libvpx**,
       **ffmpeg** **-h** **encoder=libvpx-vp9** or **vpxenc** **--help**. Further information is available in the libvpx
       API documentation.

       **b** **(**_target-bitrate_**)**
           Set bitrate in bits/s. Note that FFmpeg's **b** option is expressed in bits/s, while **vpxenc**'s
           **target-bitrate** is in kilobits/s.

       **g** **(**_kf-max-dist_**)**
       **keyint**___**min** **(**_kf-min-dist_**)**
       **qmin** **(**_min-q_**)**
       **qmax** **(**_max-q_**)**
       **bufsize** **(**_buf-sz_**,** _buf-optimal-sz_**)**
           Set ratecontrol buffer size (in bits). Note **vpxenc**'s options are specified in
           milliseconds, the libvpx wrapper converts this value as follows: "buf-sz = bufsize * 1000
           / bitrate", "buf-optimal-sz = bufsize * 1000 / bitrate * 5 / 6".

       **rc**___**init**___**occupancy** **(**_buf-initial-sz_**)**
           Set number of bits which should be loaded into the rc buffer before decoding starts. Note
           **vpxenc**'s option is specified in milliseconds, the libvpx wrapper converts this value as
           follows: "rc_init_occupancy * 1000 / bitrate".

### undershoot-pct
           Set datarate undershoot (min) percentage of the target bitrate.

### overshoot-pct
           Set datarate overshoot (max) percentage of the target bitrate.

       **skip**___**threshold** **(**_drop-frame_**)**
       **qcomp** **(**_bias-pct_**)**
       **maxrate** **(**_maxsection-pct_**)**
           Set GOP max bitrate in bits/s. Note **vpxenc**'s option is specified as a percentage of the
           target bitrate, the libvpx wrapper converts this value as follows: "(maxrate * 100 /
           bitrate)".

       **minrate** **(**_minsection-pct_**)**
           Set GOP min bitrate in bits/s. Note **vpxenc**'s option is specified as a percentage of the
           target bitrate, the libvpx wrapper converts this value as follows: "(minrate * 100 /
           bitrate)".

       **minrate,** **maxrate,** **b** _end-usage=cbr_
           "(minrate == maxrate == bitrate)".

       **crf** **(**_end-usage=cq_**,** _cq-level_**)**
       **tune** **(**_tune_**)**
           **psnr** **(**_psnr_**)**
           **ssim** **(**_ssim_**)**
       **quality,** **deadline** **(**_deadline_**)**
           **best**
               Use best quality deadline. Poorly named and quite slow, this option should be avoided
               as it may give worse quality output than good.

           **good**
               Use good quality deadline. This is a good trade-off between speed and quality when
               used with the **cpu-used** option.

           **realtime**
               Use realtime quality deadline.

       **speed,** **cpu-used** **(**_cpu-used_**)**
           Set quality/speed ratio modifier. Higher values speed up the encode at the cost of
           quality.

       **nr** **(**_noise-sensitivity_**)**
### static-thresh
           Set a change threshold on blocks below which they will be skipped by the encoder.

       **slices** **(**_token-parts_**)**
           Note that FFmpeg's **slices** option gives the total number of partitions, while **vpxenc**'s
           **token-parts** is given as "log2(partitions)".

### max-intra-rate
           Set maximum I-frame bitrate as a percentage of the target bitrate. A value of 0 means
           unlimited.

       **force**___**key**___**frames**
           "VPX_EFLAG_FORCE_KF"

### Alternate reference frame related
           **auto-alt-ref**
               Enable use of alternate reference frames (2-pass only).  Values greater than 1 enable
               multi-layer alternate reference frames (VP9 only).

           **arnr-maxframes**
               Set altref noise reduction max frame count.

           **arnr-type**
               Set altref noise reduction filter type: backward, forward, centered.

           **arnr-strength**
               Set altref noise reduction filter strength.

           **rc-lookahead,** **lag-in-frames** **(**_lag-in-frames_**)**
               Set number of frames to look ahead for frametype and ratecontrol.

### error-resilient
           Enable error resiliency features.

       **sharpness** _integer_
           Increase sharpness at the expense of lower PSNR.  The valid range is [0, 7].

### ts-parameters
           Sets the temporal scalability configuration using a :-separated list of key=value pairs.
           For example, to specify temporal scalability parameters with "ffmpeg":

                   ffmpeg -i INPUT -c:v libvpx -ts-parameters ts_number_layers=3:\
                   ts_target_bitrate=250,500,1000:ts_rate_decimator=4,2,1:\
                   ts_periodicity=4:ts_layer_id=0,2,1,2:ts_layering_mode=3 OUTPUT

           Below is a brief explanation of each of the parameters, please refer to "struct
           vpx_codec_enc_cfg" in "vpx/vpx_encoder.h" for more details.

           **ts**___**number**___**layers**
               Number of temporal coding layers.

           **ts**___**target**___**bitrate**
               Target bitrate for each temporal layer (in kbps).  (bitrate should be inclusive of
               the lower temporal layer).

           **ts**___**rate**___**decimator**
               Frame rate decimation factor for each temporal layer.

           **ts**___**periodicity**
               Length of the sequence defining frame temporal layer membership.

           **ts**___**layer**___**id**
               Template defining the membership of frames to temporal layers.

           **ts**___**layering**___**mode**
               (optional) Selecting the temporal structure from a set of pre-defined temporal
               layering modes.  Currently supports the following options.

               **0**   No temporal layering flags are provided internally, relies on flags being passed
                   in using "metadata" field in "AVFrame" with following keys.

                   **vp8-flags**
                       Sets the flags passed into the encoder to indicate the referencing scheme for
                       the current frame.  Refer to function "vpx_codec_encode" in
                       "vpx/vpx_encoder.h" for more details.

                   **temporal**___**id**
                       Explicitly sets the temporal id of the current frame to encode.

               **2**   Two temporal layers. 0-1...

               **3**   Three temporal layers. 0-2-1-2...; with single reference frame.

               **4**   Same as option "3", except there is a dependency between the two temporal layer 2
                   frames within the temporal period.

### VP9-specific options
           **lossless**
               Enable lossless mode.

           **tile-columns**
               Set number of tile columns to use. Note this is given as "log2(tile_columns)". For
               example, 8 tile columns would be requested by setting the **tile-columns** option to 3.

           **tile-rows**
               Set number of tile rows to use. Note this is given as "log2(tile_rows)".  For
               example, 4 tile rows would be requested by setting the **tile-rows** option to 2.

           **frame-parallel**
               Enable frame parallel decodability features.

           **aq-mode**
               Set adaptive quantization mode (0: off (default), 1: variance 2: complexity, 3:
               cyclic refresh, 4: equator360).

           **colorspace** _color-space_
               Set input color space. The VP9 bitstream supports signaling the following
               colorspaces:

               **rgb** _s_s_R_R_G_G_B_B
               **bt709** _b_b_t_t_7_7_0_0_9_9
               **unspecified** _u_u_n_n_k_k_n_n_o_o_w_w_n_n
               **bt470bg** _b_b_t_t_6_6_0_0_1_1
               **smpte170m** _s_s_m_m_p_p_t_t_e_e_1_1_7_7_0_0
               **smpte240m** _s_s_m_m_p_p_t_t_e_e_2_2_4_4_0_0
               **bt2020**___**ncl** _b_b_t_t_2_2_0_0_2_2_0_0
           **row-mt** _boolean_
               Enable row based multi-threading.

           **tune-content**
               Set content type: default (0), screen (1), film (2).

           **corpus-complexity**
               Corpus VBR mode is a variant of standard VBR where the complexity distribution
               midpoint is passed in rather than calculated for a specific clip or chunk.

               The valid range is [0, 10000]. 0 (default) uses standard VBR.

           **enable-tpl** _boolean_
               Enable temporal dependency model.

           **ref-frame-config**
               Using per-frame metadata, set members of the structure "vpx_svc_ref_frame_config_t"
               in "vpx/vp8cx.h" to fine-control referencing schemes and frame buffer management.
               Use a :-separated list of key=value pairs.  For example,

                       av_dict_set(&av_frame->metadata, "ref-frame-config", \
                       "rfc_update_buffer_slot=7:rfc_lst_fb_idx=0:rfc_gld_fb_idx=1:rfc_alt_fb_idx=2:rfc_reference_last=0:rfc_reference_golden=0:rfc_reference_alt_ref=0");

               **rfc**___**update**___**buffer**___**slot**
                   Indicates the buffer slot number to update

               **rfc**___**update**___**last**
                   Indicates whether to update the LAST frame

               **rfc**___**update**___**golden**
                   Indicates whether to update GOLDEN frame

               **rfc**___**update**___**alt**___**ref**
                   Indicates whether to update ALT_REF frame

               **rfc**___**lst**___**fb**___**idx**
                   LAST frame buffer index

               **rfc**___**gld**___**fb**___**idx**
                   GOLDEN frame buffer index

               **rfc**___**alt**___**fb**___**idx**
                   ALT_REF frame buffer index

               **rfc**___**reference**___**last**
                   Indicates whether to reference LAST frame

               **rfc**___**reference**___**golden**
                   Indicates whether to reference GOLDEN frame

               **rfc**___**reference**___**alt**___**ref**
                   Indicates whether to reference ALT_REF frame

               **rfc**___**reference**___**duration**
                   Indicates frame duration

       For more information about libvpx see: <**<http://www.webmproject.org/>**>

### 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.

       _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.

       _Options_

### -lossless
           Enables/Disables use of lossless mode. Default is 0.

### -compression
           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 _method_ option in libwebp. The
           valid range is 0 to 6.  Default is 4.

### -qscale
           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 _global_quality_ and must be
           multiplied by _FF_QP2LAMBDA_.

### -preset
           Configuration preset. This does some automatic settings based on the general type of the
           image.

           **none**
               Do not use a preset.

           **default**
               Use the encoder default.

           **picture**
               Digital picture, like portrait, inner shot

           **photo**
               Outdoor photograph, with natural lighting

           **drawing**
               Hand or line drawing, with high-contrast details

           **icon**
               Small-sized colorful images

           **text**
               Text-like

### libx264, libx264rgb
       x264 H.264/MPEG-4 AVC encoder wrapper.

       This encoder requires the presence of the libx264 headers and library during configuration.
       You need to explicitly configure the build with "--enable-libx264".

       libx264 supports an impressive number of features, including 8x8 and 4x4 adaptive spatial
       transform, adaptive B-frame placement, CAVLC/CABAC entropy coding, interlacing (MBAFF),
       lossless mode, psy optimizations for detail retention (adaptive quantization, psy-RD, psy-
       trellis).

       Many libx264 encoder options are mapped to FFmpeg global codec options, while unique encoder
       options are provided through private options. Additionally the **x264opts** and **x264-params**
       private options allows one to pass a list of key=value tuples as accepted by the libx264
       "x264_param_parse" function.

       The x264 project website is at <**<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.

       _Supported_ _Pixel_ _Formats_

       x264 supports 8- to 10-bit color spaces. The exact bit depth is controlled at x264's
       configure time.

       _Options_

       The following options are supported by the libx264 wrapper. The **x264**-equivalent options or
       values are listed in parentheses for easy migration.

       To reduce the duplication of documentation, only the private options and some others
       requiring special attention are documented here. For the documentation of the undocumented
       generic options, see **the** **Codec** **Options** **chapter**.

       To get a more accurate and extensive documentation of the libx264 options, invoke the command
       **x264** **--fullhelp** or consult the libx264 documentation.

       **b** **(**_bitrate_**)**
           Set bitrate in bits/s. Note that FFmpeg's **b** option is expressed in bits/s, while **x264**'s
           **bitrate** is in kilobits/s.

       **bf** **(**_bframes_**)**
       **g** **(**_keyint_**)**
       **qmin** **(**_qpmin_**)**
           Minimum quantizer scale.

       **qmax** **(**_qpmax_**)**
           Maximum quantizer scale.

       **qdiff** **(**_qpstep_**)**
           Maximum difference between quantizer scales.

       **qblur** **(**_qblur_**)**
           Quantizer curve blur

       **qcomp** **(**_qcomp_**)**
           Quantizer curve compression factor

       **refs** **(**_ref_**)**
           Number of reference frames each P-frame can use. The range is from _0-16_.

       **sc**___**threshold** **(**_scenecut_**)**
           Sets the threshold for the scene change detection.

       **trellis** **(**_trellis_**)**
           Performs Trellis quantization to increase efficiency. Enabled by default.

       **nr**  **(**_nr_**)**
       **me**___**range** **(**_merange_**)**
           Maximum range of the motion search in pixels.

       **me**___**method** **(**_me_**)**
           Set motion estimation method. Possible values in the decreasing order of speed:

           **dia** **(**_dia_**)**
           **epzs** **(**_dia_**)**
               Diamond search with radius 1 (fastest). **epzs** is an alias for **dia**.

           **hex** **(**_hex_**)**
               Hexagonal search with radius 2.

           **umh** **(**_umh_**)**
               Uneven multi-hexagon search.

           **esa** **(**_esa_**)**
               Exhaustive search.

           **tesa** **(**_tesa_**)**
               Hadamard exhaustive search (slowest).

### forced-idr
           Normally, when forcing a I-frame type, the encoder can select any type of I-frame. This
           option forces it to choose an IDR-frame.

       **subq** **(**_subme_**)**
           Sub-pixel motion estimation method.

       **b**___**strategy** **(**_b-adapt_**)**
           Adaptive B-frame placement decision algorithm. Use only on first-pass.

       **keyint**___**min** **(**_min-keyint_**)**
           Minimum GOP size.

### coder
           Set entropy encoder. Possible values:

           **ac**  Enable CABAC.

           **vlc** Enable CAVLC and disable CABAC. It generates the same effect as **x264**'s **--no-cabac**
               option.

       **cmp** Set full pixel motion estimation comparison algorithm. Possible values:

           **chroma**
               Enable chroma in motion estimation.

           **sad** Ignore chroma in motion estimation. It generates the same effect as **x264**'s
               **--no-chroma-me** option.

       **threads** **(**_threads_**)**
           Number of encoding threads.

       **thread**___**type**
           Set multithreading technique. Possible values:

           **slice**
               Slice-based multithreading. It generates the same effect as **x264**'s **--sliced-threads**
               option.

           **frame**
               Frame-based multithreading.

### flags
           Set encoding flags. It can be used to disable closed GOP and enable open GOP by setting
           it to "-cgop". The result is similar to the behavior of **x264**'s **--open-gop** option.

       **rc**___**init**___**occupancy** **(**_vbv-init_**)**
       **preset** **(**_preset_**)**
           Set the encoding preset.

       **tune** **(**_tune_**)**
           Set tuning of the encoding params.

       **profile** **(**_profile_**)**
           Set profile restrictions.

### fastfirstpass
           Enable fast settings when encoding first pass, when set to 1. When set to 0, it has the
           same effect of **x264**'s **--slow-firstpass** option.

       **crf** **(**_crf_**)**
           Set the quality for constant quality mode.

       **crf**___**max** **(**_crf-max_**)**
           In CRF mode, prevents VBV from lowering quality beyond this point.

       **qp** **(**_qp_**)**
           Set constant quantization rate control method parameter.

       **aq-mode** **(**_aq-mode_**)**
           Set AQ method. Possible values:

           **none** **(**_0_**)**
               Disabled.

           **variance** **(**_1_**)**
               Variance AQ (complexity mask).

           **autovariance** **(**_2_**)**
               Auto-variance AQ (experimental).

       **aq-strength** **(**_aq-strength_**)**
           Set AQ strength, reduce blocking and blurring in flat and textured areas.

       **psy** Use psychovisual optimizations when set to 1. When set to 0, it has the same effect as
           **x264**'s **--no-psy** option.

       **psy-rd**  **(**_psy-rd_**)**
           Set strength of psychovisual optimization, in _psy-rd_:_psy-trellis_ format.

       **rc-lookahead** **(**_rc-lookahead_**)**
           Set number of frames to look ahead for frametype and ratecontrol.

### weightb
           Enable weighted prediction for B-frames when set to 1. When set to 0, it has the same
           effect as **x264**'s **--no-weightb** option.

       **weightp** **(**_weightp_**)**
           Set weighted prediction method for P-frames. Possible values:

           **none** **(**_0_**)**
               Disabled

           **simple** **(**_1_**)**
               Enable only weighted refs

           **smart** **(**_2_**)**
               Enable both weighted refs and duplicates

       **ssim** **(**_ssim_**)**
           Enable calculation and printing SSIM stats after the encoding.

       **intra-refresh** **(**_intra-refresh_**)**
           Enable the use of Periodic Intra Refresh instead of IDR frames when set to 1.

       **avcintra-class** **(**_class_**)**
           Configure the encoder to generate AVC-Intra.  Valid values are 50,100 and 200

       **bluray-compat** **(**_bluray-compat_**)**
           Configure the encoder to be compatible with the bluray standard.  It is a shorthand for
           setting "bluray-compat=1 force-cfr=1".

       **b-bias** **(**_b-bias_**)**
           Set the influence on how often B-frames are used.

       **b-pyramid** **(**_b-pyramid_**)**
           Set method for keeping of some B-frames as references. Possible values:

           **none** **(**_none_**)**
               Disabled.

           **strict** **(**_strict_**)**
               Strictly hierarchical pyramid.

           **normal** **(**_normal_**)**
               Non-strict (not Blu-ray compatible).

### 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 **x264**'s **--no-mixed-refs** option.

### 8x8dct
           Enable adaptive spatial transform (high profile 8x8 transform) when set to 1. When set to
           0, it has the same effect as **x264**'s **--no-8x8dct** option.

### fast-pskip
           Enable early SKIP detection on P-frames when set to 1. When set to 0, it has the same
           effect as **x264**'s **--no-fast-pskip** option.

       **aud** **(**_aud_**)**
           Enable use of access unit delimiters when set to 1.

### mbtree
           Enable use macroblock tree ratecontrol when set to 1. When set to 0, it has the same
           effect as **x264**'s **--no-mbtree** option.

       **deblock** **(**_deblock_**)**
           Set loop filter parameters, in _alpha_:_beta_ form.

       **cplxblur** **(**_cplxblur_**)**
           Set fluctuations reduction in QP (before curve compression).

       **partitions** **(**_partitions_**)**
           Set partitions to consider as a comma-separated list of. Possible values in the list:

           **p8x8**
               8x8 P-frame partition.

           **p4x4**
               4x4 P-frame partition.

           **b8x8**
               4x4 B-frame partition.

           **i8x8**
               8x8 I-frame partition.

           **i4x4**
               4x4 I-frame partition.  (Enabling **p4x4** requires **p8x8** to be enabled. Enabling **i8x8**
               requires adaptive spatial transform (**8x8dct** option) to be enabled.)

           **none** **(**_none_**)**
               Do not consider any partitions.

           **all** **(**_all_**)**
               Consider every partition.

       **direct-pred** **(**_direct_**)**
           Set direct MV prediction mode. Possible values:

           **none** **(**_none_**)**
               Disable MV prediction.

           **spatial** **(**_spatial_**)**
               Enable spatial predicting.

           **temporal** **(**_temporal_**)**
               Enable temporal predicting.

           **auto** **(**_auto_**)**
               Automatically decided.

       **slice-max-size** **(**_slice-max-size_**)**
           Set the limit of the size of each slice in bytes. If not specified but RTP payload size
           (**ps**) is specified, that is used.

       **stats** **(**_stats_**)**
           Set the file name for multi-pass stats.

       **nal-hrd** **(**_nal-hrd_**)**
           Set signal HRD information (requires **vbv-bufsize** to be set).  Possible values:

           **none** **(**_none_**)**
               Disable HRD information signaling.

           **vbr** **(**_vbr_**)**
               Variable bit rate.

           **cbr** **(**_cbr_**)**
               Constant bit rate (not allowed in MP4 container).

### x264opts (N.A.)
           Set any x264 option, see **x264** **--fullhelp** for a list.

           Argument is a list of _key_=_value_ couples separated by ":". In _filter_ and _psy-rd_ options
           that use ":" as a separator themselves, use "," instead. They accept it as well since
           long ago but this is kept undocumented for some reason.

           For example to specify libx264 encoding options with **ffmpeg**:

                   ffmpeg -i foo.mpg -c:v libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv

       **a53cc** _boolean_
           Import closed captions (which must be ATSC compatible format) into output.  Only the
           mpeg2 and h264 decoders provide these. Default is 1 (on).

### x264-params (N.A.)
           Override the x264 configuration using a :-separated list of key=value parameters.

           This option is functionally the same as the **x264opts**, but is duplicated for compatibility
           with the Libav fork.

           For example to specify libx264 encoding options with **ffmpeg**:

                   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

       Encoding ffpresets for common usages are provided so they can be used with the general
       presets system (e.g. passing the **pre** option).

### libx265
       x265 H.265/HEVC encoder wrapper.

       This encoder requires the presence of the libx265 headers and library during configuration.
       You need to explicitly configure the build with **--enable-libx265**.

       _Options_

       **b**   Sets target video bitrate.

       **bf**
       **g**   Set the GOP size.

       **keyint**___**min**
           Minimum GOP size.

### refs
           Number of reference frames each P-frame can use. The range is from _1-16_.

### preset
           Set the x265 preset.

### tune
           Set the x265 tune parameter.

### profile
           Set profile restrictions.

       **crf** Set the quality for constant quality mode.

       **qp**  Set constant quantization rate control method parameter.

### qmin
           Minimum quantizer scale.

### qmax
           Maximum quantizer scale.

### qdiff
           Maximum difference between quantizer scales.

### qblur
           Quantizer curve blur

### qcomp
           Quantizer curve compression factor

       **i**___**qfactor**
       **b**___**qfactor**
### forced-idr
           Normally, when forcing a I-frame type, the encoder can select any type of I-frame. This
           option forces it to choose an IDR-frame.

### x265-params
           Set x265 options using a list of _key_=_value_ couples separated by ":". See **x265** **--help** for
           a list of options.

           For example to specify libx265 encoding options with **-x265-params**:

                   ffmpeg -i input -c:v libx265 -x265-params crf=26:psy-rd=1 output.mp4

### libxavs2
       xavs2 AVS2-P2/IEEE1857.4 encoder wrapper.

       This encoder requires the presence of the libxavs2 headers and library during configuration.
       You need to explicitly configure the build with **--enable-libxavs2**.

       The following standard libavcodec options are used:

       •   **b** / **bit**___**rate**

       •   **g** / **gop**___**size**

       •   **bf** / **max**___**b**___**frames**

       The encoder also has its own specific options:

       _Options_

       **lcu**___**row**___**threads**
           Set the number of parallel threads for rows from 1 to 8 (default 5).

       **initial**___**qp**
           Set the xavs2 quantization parameter from 1 to 63 (default 34). This is used to set the
           initial qp for the first frame.

       **qp**  Set the xavs2 quantization parameter from 1 to 63 (default 34). This is used to set the
           qp value under constant-QP mode.

       **max**___**qp**
           Set the max qp for rate control from 1 to 63 (default 55).

       **min**___**qp**
           Set the min qp for rate control from 1 to 63 (default 20).

       **speed**___**level**
           Set the Speed level from 0 to 9 (default 0). Higher is better but slower.

       **log**___**level**
           Set the log level from -1 to 3 (default 0). -1: none, 0: error, 1: warning, 2: info, 3:
           debug.

### xavs2-params
           Set xavs2 options using a list of _key_=_value_ couples separated by ":".

           For example to specify libxavs2 encoding options with **-xavs2-params**:

                   ffmpeg -i input -c:v libxavs2 -xavs2-params RdoqLevel=0 output.avs2

### 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 "--enable-libxvid
       --enable-gpl".

       The native "mpeg4" encoder supports the MPEG-4 Part 2 format, so users can encode to this
       format without this library.

       _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 **the** **Codec** **Options**
       **chapter** for their documentation. The other shared options which are not listed have no effect
       for the libxvid encoder.

       **b**
       **g**
### qmin
### qmax
       **mpeg**___**quant**
### threads
       **bf**
       **b**___**qfactor**
       **b**___**qoffset**
### flags
           Set specific encoding flags. Possible values:

           **mv4** Use four motion vector by macroblock.

           **aic** Enable high quality AC prediction.

           **gray**
               Only encode grayscale.

           **gmc** Enable the use of global motion compensation (GMC).

           **qpel**
               Enable quarter-pixel motion compensation.

           **cgop**
               Enable closed GOP.

           **global**___**header**
               Place global headers in extradata instead of every keyframe.

### trellis
       **me**___**method**
           Set motion estimation method. Possible values in decreasing order of speed and increasing
           order of quality:

           **zero**
               Use no motion estimation (default).

           **phods**
           **x1**
           **log** Enable advanced diamond zonal search for 16x16 blocks and half-pixel refinement for
               16x16 blocks. **x1** and **log** are aliases for **phods**.

           **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.

           **full**
               Enable all of the things described above, plus extended 16x16 and 8x8 blocks search.

       **mbd** Set macroblock decision algorithm. Possible values in the increasing order of quality:

           **simple**
               Use macroblock comparing function algorithm (default).

           **bits**
               Enable rate distortion-based half pixel and quarter pixel refinement for 16x16
               blocks.

           **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.

       **lumi**___**aq**
           Enable lumi masking adaptive quantization when set to 1. Default is 0 (disabled).

       **variance**___**aq**
           Enable variance adaptive quantization when set to 1. Default is 0 (disabled).

           When combined with **lumi**___**aq**, the resulting quality will not be better than any of the two
           specified individually. In other words, the resulting quality will be the worse one of
           the two effects.

### ssim
           Set structural similarity (SSIM) displaying method. Possible values:

           **off** Disable displaying of SSIM information.

           **avg** Output average SSIM at the end of encoding to stdout. The format of showing the
               average SSIM is:

                       Average SSIM: %f

               For users who are not familiar with C, %f means a float number, or a decimal (e.g.
               0.939232).

           **frame**
               Output both per-frame SSIM data during encoding and average SSIM at the end of
               encoding to stdout. The format of per-frame information is:

                              SSIM: avg: %1.3f min: %1.3f max: %1.3f

               For users who are not familiar with C, %1.3f means a float number rounded to 3 digits
               after the dot (e.g. 0.932).

       **ssim**___**acc**
           Set SSIM accuracy. Valid options are integers within the range of 0-4, while 0 gives the
           most accurate result and 4 computes the fastest.

### MediaFoundation
       This provides wrappers to encoders (both audio and video) in the MediaFoundation framework.
       It can access both SW and HW encoders.  Video encoders can take input in either of nv12 or
       yuv420p form (some encoders support both, some support only either - in practice, nv12 is the
       safer choice, especially among HW encoders).

### mpeg2
       MPEG-2 video encoder.

       _Options_

### profile
           Select the mpeg2 profile to encode:

           **422**
           **high**
           **ss**  Spatially Scalable

           **snr** SNR Scalable

           **main**
           **simple**
### level
           Select the mpeg2 level to encode:

           **high**
           **high1440**
           **main**
           **low**
       **seq**___**disp**___**ext** _integer_
           Specifies if the encoder should write a sequence_display_extension to the output.

           **-1**
           **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.

           **0**
           **never**
               Never write it.

           **1**
           **always**
               Always write it.

       **video**___**format** _integer_
           Specifies the video_format written into the sequence display extension indicating the
           source of the video pictures. The default is **unspecified**, can be **component**, **pal**, **ntsc**,
           **secam** or **mac**.  For maximum compatibility, use **component**.

       **a53cc** _boolean_
           Import closed captions (which must be ATSC compatible format) into output.  Default is 1
           (on).

### png
       PNG image encoder.

       _Private_ _options_

       **dpi** _integer_
           Set physical density of pixels, in dots per inch, unset by default

       **dpm** _integer_
           Set physical density of pixels, in dots per meter, unset by default

### ProRes
       Apple ProRes encoder.

       FFmpeg contains 2 ProRes encoders, the prores-aw and prores-ks encoder.  The used encoder can
       be chosen with the "-vcodec" option.

       _Private_ _Options_ _for_ _prores-ks_

       **profile** _integer_
           Select the ProRes profile to encode

           **proxy**
           **lt**
           **standard**
           **hq**
           **4444**
           **4444xq**
       **quant**___**mat** _integer_
           Select quantization matrix.

           **auto**
           **default**
           **proxy**
           **lt**
           **standard**
           **hq**

           If set to _auto_, the matrix matching the profile will be picked.  If not set, the matrix
           providing the highest quality, _default_, will be picked.

       **bits**___**per**___**mb** _integer_
           How many bits to allot for coding one macroblock. Different profiles use between 200 and
           2400 bits per macroblock, the maximum is 8000.

       **mbs**___**per**___**slice** _integer_
           Number of macroblocks in each slice (1-8); the default value (8) should be good in almost
           all situations.

       **vendor** _string_
           Override the 4-byte vendor ID.  A custom vendor ID like _apl0_ would claim the stream was
           produced by the Apple encoder.

       **alpha**___**bits** _integer_
           Specify number of bits for alpha component.  Possible values are _0_, _8_ and _16_.  Use _0_ to
           disable alpha plane coding.

       _Speed_ _considerations_

       In the default mode of operation the encoder has to honor frame constraints (i.e. not produce
       frames with size bigger than requested) while still making output picture as good as
       possible.  A frame containing a lot of small details is harder to compress and the encoder
       would spend more time searching for appropriate quantizers for each slice.

       Setting a higher **bits**___**per**___**mb** limit will improve the speed.

       For the fastest encoding speed set the **qscale** parameter (4 is the recommended value) and do
       not set a size constraint.

### QSV encoders
       The family of Intel QuickSync Video encoders (MPEG-2, H.264, HEVC, JPEG/MJPEG and VP9)

       The ratecontrol method is selected as follows:

       •   When **global**___**quality** is specified, a quality-based mode is used.  Specifically this means
           either

           -   _CQP_ - constant quantizer scale, when the **qscale** codec flag is also set (the **-qscale**
               ffmpeg option).

           -   _LA_ICQ_ - intelligent constant quality with lookahead, when the **look**___**ahead** option is
               also set.

           -   _ICQ_ -- intelligent constant quality otherwise.

       •   Otherwise, a bitrate-based mode is used. For all of those, you should specify at least
           the desired average bitrate with the **b** option.

           -   _LA_ - VBR with lookahead, when the **look**___**ahead** option is specified.

           -   _VCM_ - video conferencing mode, when the **vcm** option is set.

           -   _CBR_ - constant bitrate, when **maxrate** is specified and equal to the average bitrate.

           -   _VBR_ - variable bitrate, when **maxrate** is specified, but is higher than the average
               bitrate.

           -   _AVBR_ - average VBR mode, when **maxrate** is not specified. This mode is further
               configured by the **avbr**___**accuracy** and **avbr**___**convergence** options.

       Note that depending on your system, a different mode than the one you specified may be
       selected by the encoder. Set the verbosity level to _verbose_ or higher to see the actual
       settings used by the QSV runtime.

       Additional libavcodec global options are mapped to MSDK options as follows:

       •   **g/gop**___**size** -> **GopPicSize**

       •   **bf/max**___**b**___**frames**+1 -> **GopRefDist**

       •   **rc**___**init**___**occupancy/rc**___**initial**___**buffer**___**occupancy** -> **InitialDelayInKB**

       •   **slices** -> **NumSlice**

       •   **refs** -> **NumRefFrame**

       •   **b**___**strategy/b**___**frame**___**strategy** -> **BRefType**

       •   **cgop/CLOSED**___**GOP** codec flag -> **GopOptFlag**

       •   For the _CQP_ mode, the **i**___**qfactor/i**___**qoffset** and **b**___**qfactor/b**___**qoffset** set the difference
           between _QPP_ and _QPI_, and _QPP_ and _QPB_ respectively.

       •   Setting the **coder** option to the value _vlc_ will make the H.264 encoder use CAVLC instead
           of CABAC.

### snow
       _Options_

       **iterative**___**dia**___**size**
           dia size for the iterative motion estimation

### VAAPI encoders
       Wrappers for hardware encoders accessible via VAAPI.

       These encoders only accept input in VAAPI hardware surfaces.  If you have input in software
       frames, use the **hwupload** filter to upload them to the GPU.

       The following standard libavcodec options are used:

       •   **g** / **gop**___**size**

       •   **bf** / **max**___**b**___**frames**

       •   **profile**

           If not set, this will be determined automatically from the format of the input frames and
           the profiles supported by the driver.

       •   **level**

       •   **b** / **bit**___**rate**

       •   **maxrate** / **rc**___**max**___**rate**

       •   **bufsize** / **rc**___**buffer**___**size**

       •   **rc**___**init**___**occupancy** / **rc**___**initial**___**buffer**___**occupancy**

       •   **compression**___**level**

           Speed / quality tradeoff: higher values are faster / worse quality.

       •   **q** / **global**___**quality**

           Size / quality tradeoff: higher values are smaller / worse quality.

       •   **qmin**

       •   **qmax**

       •   **i**___**qfactor** / **i**___**quant**___**factor**

       •   **i**___**qoffset** / **i**___**quant**___**offset**

       •   **b**___**qfactor** / **b**___**quant**___**factor**

       •   **b**___**qoffset** / **b**___**quant**___**offset**

       •   **slices**

       All encoders support the following options:

       **low**___**power**
           Some drivers/platforms offer a second encoder for some codecs intended to use less power
           than the default encoder; setting this option will attempt to use that encoder.  Note
           that it may support a reduced feature set, so some other options may not be available in
           this mode.

       **idr**___**interval**
           Set the number of normal intra frames between full-refresh (IDR) frames in open-GOP mode.
           The intra frames are still IRAPs, but will not include global headers and may have non-
           decodable leading pictures.

       **b**___**depth**
           Set the B-frame reference depth.  When set to one (the default), all B-frames will refer
           only to P- or I-frames.  When set to greater values multiple layers of B-frames will be
           present, frames in each layer only referring to frames in higher layers.

       **rc**___**mode**
           Set the rate control mode to use.  A given driver may only support a subset of modes.

           Possible modes:

           **auto**
               Choose the mode automatically based on driver support and the other options.  This is
               the default.

           **CQP** Constant-quality.

           **CBR** Constant-bitrate.

           **VBR** Variable-bitrate.

           **ICQ** Intelligent constant-quality.

           **QVBR**
               Quality-defined variable-bitrate.

           **AVBR**
               Average variable bitrate.

       Each encoder also has its own specific options:

       **h264**___**vaapi**
           **profile** sets the value of _profile_idc_ and the _constraint_set*_flag_s.  **level** sets the
           value of _level_idc_.

           **coder**
               Set entropy encoder (default is _cabac_).  Possible values:

               **ac**
               **cabac**
                   Use CABAC.

               **vlc**
               **cavlc**
                   Use CAVLC.

           **aud** Include access unit delimiters in the stream (not included by default).

           **sei** Set SEI message types to include.  Some combination of the following values:

               **identifier**
                   Include a _user_data_unregistered_ message containing information about the
                   encoder.

               **timing**
                   Include picture timing parameters (_buffering_period_ and _pic_timing_ messages).

               **recovery**___**point**
                   Include recovery points where appropriate (_recovery_point_ messages).

       **hevc**___**vaapi**
           **profile** and **level** set the values of _general_profile_idc_ and _general_level_idc_
           respectively.

           **aud** Include access unit delimiters in the stream (not included by default).

           **tier**
               Set _general_tier_flag_.  This may affect the level chosen for the stream if it is not
               explicitly specified.

           **sei** Set SEI message types to include.  Some combination of the following values:

               **hdr** Include HDR metadata if the input frames have it (_mastering_display_colour_volume_
                   and _content_light_level_ messages).

           **tiles**
               Set the number of tiles to encode the input video with, as columns x rows.  Larger
               numbers allow greater parallelism in both encoding and decoding, but may decrease
               coding efficiency.

       **mjpeg**___**vaapi**
           Only baseline DCT encoding is supported.  The encoder always uses the standard
           quantisation and huffman tables - **global**___**quality** scales the standard quantisation table
           (range 1-100).

           For YUV, 4:2:0, 4:2:2 and 4:4:4 subsampling modes are supported.  RGB is also supported,
           and will create an RGB JPEG.

           **jfif**
               Include JFIF header in each frame (not included by default).

           **huffman**
               Include standard huffman tables (on by default).  Turning this off will save a few
               hundred bytes in each output frame, but may lose compatibility with some JPEG
               decoders which don't fully handle MJPEG.

       **mpeg2**___**vaapi**
           **profile** and **level** set the value of _profile_and_level_indication_.

       **vp8**___**vaapi**
           B-frames are not supported.

           **global**___**quality** sets the _q_idx_ used for non-key frames (range 0-127).

           **loop**___**filter**___**level**
           **loop**___**filter**___**sharpness**
               Manually set the loop filter parameters.

       **vp9**___**vaapi**
           **global**___**quality** sets the _q_idx_ used for P-frames (range 0-255).

           **loop**___**filter**___**level**
           **loop**___**filter**___**sharpness**
               Manually set the loop filter parameters.

           B-frames are supported, but the output stream is always in encode order rather than
           display order.  If B-frames are enabled, it may be necessary to use the **vp9**___**raw**___**reorder**
           bitstream filter to modify the output stream to display frames in the correct order.

           Only normal frames are produced - the **vp9**___**superframe** bitstream filter may be required to
           produce a stream usable with all decoders.

### vc2
       SMPTE VC-2 (previously BBC Dirac Pro). This codec was primarily aimed at professional
       broadcasting but since it supports yuv420, yuv422 and yuv444 at 8 (limited range or full
       range), 10 or 12 bits, this makes it suitable for other tasks which require low overhead and
       low compression (like screen recording).

       _Options_

       **b**   Sets target video bitrate. Usually that's around 1:6 of the uncompressed video bitrate
           (e.g. for 1920x1080 50fps yuv422p10 that's around 400Mbps). Higher values (close to the
           uncompressed bitrate) turn on lossless compression mode.

       **field**___**order**
           Enables field coding when set (e.g. to tt - top field first) for interlaced inputs.
           Should increase compression with interlaced content as it splits the fields and encodes
           each separately.

       **wavelet**___**depth**
           Sets the total amount of wavelet transforms to apply, between 1 and 5 (default).  Lower
           values reduce compression and quality. Less capable decoders may not be able to handle
           values of **wavelet**___**depth** over 3.

       **wavelet**___**type**
           Sets the transform type. Currently only _5_3_ (LeGall) and _9_7_ (Deslauriers-Dubuc) are
           implemented, with 9_7 being the one with better compression and thus is the default.

       **slice**___**width**
       **slice**___**height**
           Sets the slice size for each slice. Larger values result in better compression.  For
           compatibility with other more limited decoders use **slice**___**width** of 32 and **slice**___**height** of
           8.

### tolerance
           Sets the undershoot tolerance of the rate control system in percent. This is to prevent
           an expensive search from being run.

       **qm**  Sets the quantization matrix preset to use by default or when **wavelet**___**depth** is set to 5

           -   _default_ Uses the default quantization matrix from the specifications, extended with
               values for the fifth level. This provides a good balance between keeping detail and
               omitting artifacts.

           -   _flat_ Use a completely zeroed out quantization matrix. This increases PSNR but might
               reduce perception. Use in bogus benchmarks.

           -   _color_ Reduces detail but attempts to preserve color at extremely low bitrates.

## SUBTITLES ENCODERS
### 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.

       _Options_

### palette
           Specify the global palette used by the bitmaps.

           The format for this option is a string containing 16 24-bits hexadecimal numbers (without
           0x prefix) separated by commas, for example "0d00ee, ee450d, 101010, eaeaea, 0ce60b,
           ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1, 7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b".

       **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.

## SEE ALSO
       [**ffmpeg**(1)](https://www.chedong.com/phpMan.php/man/ffmpeg/1/markdown), [**ffplay**(1)](https://www.chedong.com/phpMan.php/man/ffplay/1/markdown), [**ffprobe**(1)](https://www.chedong.com/phpMan.php/man/ffprobe/1/markdown), [**libavcodec**(3)](https://www.chedong.com/phpMan.php/man/libavcodec/3/markdown)

## AUTHORS
       The FFmpeg developers.

       For details about the authorship, see the Git history of the project
       (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command **git** **log** in the FFmpeg source
       directory, or browsing the online repository at <**<http://source.ffmpeg.org>**>.

       Maintainers for the specific components are listed in the file _MAINTAINERS_ in the source code
       tree.



                                                                                    [FFMPEG-CODECS(1)](https://www.chedong.com/phpMan.php/man/FFMPEG-CODECS/1/markdown)