[FFmpeg-user] Preserve pix_fmt, regardless of codec?

[Peter B.]

On 04/27/2012 03:08 PM, Carl Eugen Hoyos wrote:
> Nicolas George <nicolas.george <at> normalesup.org> writes:
>
>> L'octidi 8 floréal, an CCXX, Carl Eugen Hoyos a écrit :
>>> Sorry, I honestly believe FFmpeg currently does exactly what 
>>> you asked.
>> Unfortunately, not at all.
> I suspect you are refering to ticket #1080, while Peter's question - 
> if I understood him correctly - was more "Does FFmpeg always force a 
> colour space or does it choose them at random?" while it actually 
> tries hard not to loose any information from the input file when 
> encoding (from a colour space perspective).
What I meant was a something similar to "-vcodec copy", but for
"pix_fmt". Just a way to tell ffmpeg that I *do* care about the pix_fmt
used in the output, but I can't force it to something specific, as in
some cases this *could* mean conversion.

Ticket #1080 is something different, as pix_fmt is specified in the
commandline, but another one was taken.

If there'd be something like "-pix_fmt copy", ffmpeg would then know
that it's important to keep the source's pix_fmt, and if it can't (for
whatever reason), it could then bail out and say: "Sorry, can't do".

Currently I think if the original pix_fmt can't be preserved, ffmpeg
would now fallback to "the next best option". This is what I'd like to
avoid.

But as I said: I don't have that case right now, I've just had some
colleagues from another video-archiving facility ask me if it'd be
possible to "assure" that it is preserved.

Thanks for your time,
Pb