[FFmpeg-user] What does ffmpeg consider metadata? -- revision

[James Darnley]

On 2020-03-04 01:02, Mark Filipak wrote:
> Kindly disregard the last message. I don't know how 'metadata' got left
> out of the command line...
> 
> To me, metadata is such MPEG settings as 'progressive_sequence',
> 'top_field_first', 'frame_pred_frame_dct', 'concealment_motion_vectors',
> 'q_scale_type',
> 'intra_vlc_format', 'alternate_scan', 'repeat_first_field',
> 'chroma_420_type', 'progressive_frame'.
> 
> What does ffmpeg consider metadata?

All of those look like bitstream features.  None of them you could
change without re-encoding or a specialized tool that can parse and
alter the bitstream.

Metadata (as ffmpeg calls it) is tags, like artist and track details on
a music file.  Plus some other things, like chapters.  To edit those
software need only understand the container or file format.

You probably cannot get the things you mentioned elevated into metadata
in ffmpeg because they are only known by separate parts, namely
libavcodec and libavformat.