[FFmpeg-devel] [PATCH 0/5] RGB48/64 with bits_per_raw_sample

[Christophe Gisquet]

Hi,

2014-08-20 20:26 GMT+02:00 Carl Eugen Hoyos <cehoyos at ag.or.at>:
> Christophe Gisquet <christophe.gisquet <at> gmail.com> writes:
>
>> Depending on the input and/or filters, you sometime
>> have an input or output pixel format like "rgb48le(12
>> bpc)". Unfortunately, most often, the 12 bpc
>> information is ignored or stripped.
>
> Could you explain what command line you are trying
> to fix?
> I apparently misunderstand the patchset, I don't
> see how / what it fixes...

The biggest "issue" is that 10/12bits data is interpreted as 16bits:
- cf. ticket #2966 (that's the remaining missing part)
- png can only write 16bits data but sometimes it is not rescaled
(image appears darker), cf. the above
- ppm images are forcibly rescaled to fill the 16bits (probably
lossless but still)
etc.

> Note that I believe it would be completely wrong to
> add additional colourspaces with 8<bpc<16.

Yes, on second thought it has its own bag of issues (multiplications
of codepaths eg in swscale), but that's to me the only solution that
isn't a fragile hack. Also note that there are already plenty of those
8<bpc<16 for planar rgb.

-- 
Christophe