[FFmpeg-user] FFV1/rgb48le issue: ffmpeg automatically chooses gbrp16le to decode an rgb48le FFV1 file.

[Kieran O Leary]

Hello Carl and Paul,

Thank you for clarifying.

On Wed, Aug 17, 2016 at 9:39 PM, Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>
> I don't think this is correct:
> FFV1 allows to encode 16 bpc RGB data. FFmpeg accepts its internal
> pix_fmts rgb48 and gbrp16 for encoding (this can be rgb48le or rgb48be
> depending on your hardware) and provides gbrp16 (again, this can be
> either gbrp16le or gbrp16be) output on decoding. I believe this is not
> very likely to change.
> Another library (or player) supporting ffv1 decoding may provide a packed
> rgb format (not necessarily rgb) on decoding or another format that also
> allows to represent 16bpc rgb.
>

This makes sense to me now. Thanks for taking the time to explain.


On Wed, Aug 17, 2016 at 9:58 PM, Paul B Mahol <onemda at gmail.com> wrote:

>
> rgb48 is packed version of gbrp16
>
> gbrp16 is planar version of rgb48.
>
> They have same information but in different memory layout.

I have one last question with regards to the different framemd5 values
when decoding the ffv1 as gbrp16le and rgb48le. I would have assumed
that these would have decoded to the same rawvideo values as they
contained the same image data, stored in a different way, but this
isn't the case? Is the different ordering of the same bits carried
over to the rawvideo and this is reflected in the framemd5 values?

Best,

Kieran.