Upscaling Colour Bit-Depth

Hello,

I was curious whether Video Enhance can upscale the colour bit depth as well as resolution?

Is there a way to feed it an 8-bit input and output 10- or 12-bit?

An example use-case would be to go from HD with 8-bit Rec.709 to UHD with 10-bit Rec.2020. (I hope I got that right, not the expert on this!)

[EDIT] In fact, what does Video Enhance currently do when you input an 8-bit TIFF (using e.g. the command line) and output a 16-TIFF? How do the colours get mapped in such a case? Is there any ‘enhancing’ that takes place at colour level to go hand in hand with an increase in resolution?

Thanks,

Jason.

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You’re definitely better off directly e-mailing support about something as technical as this. They’d be able to get back to you on that much sooner than here.

Great idea! Thanks! :slight_smile:

I read somewhere here on the forums, that VEAI works best with sRGB color space only, which is a bummer. I had material in rec709 and VEAI messed with the colors and saturation. It would be so much more useful if they could implement proper color management with OCIO. At the moment it seems to be for hobbyists only, who want to upscale their old mobile phone videos to 4K, and who don’t give a rats ass about proper colors.

From previous discussions, my understanding is ‘yes’, provided that you output in format such as Tiff 16 bit or Prores (10 bit)

Since this topic has generated some interest, I did contact technical support as follows:

If I feed in 8-bit TIFF and ask the application to output 16-bit TIFF (at a higher resolution), how does the system handle remapping the colour values?

If a pixel has a colour like (0.5, 0.5, 0.5) this would probably exist as (128,128, 128) in the 8-bit TIFF and get mapped to (32768, 32768, 32768) in 16-bit TIFF (halfway in both cases).

However my question is really: when you create a new pixel during the upscaling process, is the colour palette for this pixel restricted to the 256 colour values per channel in 8-bit, or will it use the full 65536 colour values per channel available in the 16-bit output?

Using English you could ask: do you “upscale the colour bit depth as well as the resolution”?

And the reply I got from Emily Dworkin @ Topaz was (25/05/2021):

Happy to clarify! The resolution is upscaled, the color depth is not.

Good to know, thanks!

Firstly, VEAI would have to support color mamagement and it doesn’t at the moment. It seems to treat everything as sRGB wich is the worst color space and the smallest too. The software doesn’t even know you are feeding it rec709 and thus performs the wrong kind of calculations, leaving you with an albeit sharper, yet color and saturation difference in your new video.

This is their short term road-map.

April 2.2.0 - comparison models view, fps conversion model
May 2.3.0 - Multiple I/0 fixes (frame skipping, frame cut-off on mkv, 4:2:0 chroma fix on interlaced sources & others) and codec/output additions + fps conversion models
June 2.4.0 - Better audio support
July 2.5 - Projects, separate render queue application & preset manager

I also believe they have stated the color space conversion is high priority. So 2.5 is most likely going to add a fair bit of features since they are a little behind on a few tasks.

I’m really not concerned about color space conversions at this point. with no proper handling of color management, no OCIO, no ACES, there is no way your colors are going to come out of VEAI unharmed.