[FFmpeg-user] "documented implicitly" part 2 [was: Re: Problem while converting DNG sequnece to video file]

[Moritz Barsnick]

On Thu, Aug 20, 2020 at 12:16:07 -0700, Jim DeLaHunt wrote:
> % ffmpeg -hide_banner -formats
> File formats:
>   D. = Demuxing supported
>   .E = Muxing supported
>   --
>   D  3dostr          3DO STR
> …
>   DE dirac           raw Dirac
>   DE dnxhd           raw DNxHD (SMPTE VC-3)
> …
>   D  tiertexseq      Tiertex Limited SEQ
>   D  tiff_pipe       piped tiff sequence
>   D  tmv             8088flex TMV
> …
>
> % ffmpeg -hide_banner --help demuxer=tiff_pipe
> Demuxer tiff_pipe [piped tiff sequence]:
> tiff demuxer AVOptions:
>    -frame_size        <int>        .D........ force frame size in bytes (from 0 to INT_MAX) (default 0)
>    -framerate         <video_rate> .D........ set the video framerate (default "25")
>    -pixel_format      <string>     .D........ set video pixel format
>    -video_size        <image_size> .D........ set video size
>    -loop              <boolean>    .D........ force loop over input file sequence (default false)
>
> [Note the absence of any mention of "DNG" in this documentation.]

This is not quite fair. IIUC, DNG is not a format of its own (formats
are the containers), but rather an encoding variant of a codec (TIFF).

The TIFF decoder does detect it, and could likely report "tiff (DNG)"
or something. But it won't be listed as above.

I do agree that it could and perhaps should pop up in the
documentation.

Moritz