Re: [PATCH 08/10] media: coda: allow encoder to set colorimetry on the output queue

[Philipp Zabel <p.zabel@pengutronix.de>]

On Wed, 2019-04-10 at 15:48 +0200, Hans Verkuil wrote:
[...]
> Isn't the colorimetry information encoded in the stream's metadata?

That depends on the codec. Colorimetry information can be stored in
optional headers (for example Sequence Display Extension for MPEG-2,
Video Usability Information for H.264) but I don't know that the CODA
firmware can parse or generate any of them.

> So should it be set i an encoder register so it ends up in the right
> place in the bitstream?

I could produce the necessary headers manually and inject them into the
bitstream in the driver.

But for example for JPEG it is not clear to me if there even is a
correct way to do that. Can V4L2 colorimetry settings be translated into
ICC profiles?

> And for decoders it should then be read back from a register.

Same as above, I'd have to parse the headers in the driver.

> Just curious how this would work for this codec and if it is even possible.
> 
> For now this patch is OK, but I think more work is needed.

Agreed.

regards
Philipp