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FFMPEG decoder

Register name used to load filter: ffdec
This filter may be automatically loaded during graph resolution.

This filter decodes audio and video streams using FFMPEG.
See FFMPEG documentation ( for more details.
To list all supported decoders for your GPAC build, use gpac -h ffdec:*.

Options can be passed from prompt using --OPT=VAL
The default threading mode is to let libavcodec decide how many threads to use. To enforce single thread, use --threads=1

Codec Map

The ffcmap option allows specifying FFMPEG codecs for codecs not supported by GPAC.
Each entry in the list is formatted as GID@name or GID@+name, with:
GID: 4CC or 32 bit identifier of codec ID, as indicated by gpac -i source inspect:full
name: FFMPEG codec name
* `+': is set and extra data is set and formatted as an ISOBMFF box, removes box header


gpac -i source.mp4 --ffcmap=BKV1@binkvideo vout
This will map an ISOBMFF track declared with coding type BKV1 to binkvideo.


ffcmap (strl): codec map
c (str): codec name (GPAC or ffmpeg), only used to query possible arguments - updated to ffmpeg codec name after initialization
* (str): any possible options defined for AVCodecContext and sub-classes. See gpac -hx ffdec and gpac -hx ffdec:*