Encoding HDR movie with SDR compatibility?

[Blue_MiSfit]

AFAIK Dolby Vision reconstructs 12 bit ICtCp based on the 10 bit ICtCp layer encoded as HEVC (Usually interpreted as YCbCr as far as the HEVC encoder is aware) plus the dynamic metadata. I think this is all typically sourced from 12-16 bit J2K.

I could be wrong about this though.

Compare that to HDR10 which is typically sourced from ProRes or 10 bit J2K.

[kolak]

Yes, they are and quite often it all starts from 16bit TIFF.

[Atlantis]

I was looking for this too. But at the end, I guess I have to have 2 video tracks, right? For the best quality solution, one track for HDR and one track for SDR?

[Blue_MiSfit]

Yes.

This is what premium streaming services do.

[benwaggoner]

Originally Posted by Blue_MiSfit

Yes.

This is what premium streaming services do.

And a big part of this is because the SDR and HDR masters are different source files with different creative decisions. Any "common master" format is going to require a lot of dynamic metadata at a minimum. And of course SDR-only devices won't know about any of that metadata.

The original SDR + metadata + enhancement layer model of Dolby Vision makes a ton of sense if the goal is to deliver SDR and HDR in the same stream without 2x the bitrate. It's still a good approach for Blu-ray, where capacity is a bigger limitation than bitrate.

For streaming, the DoVi single-layer HDR offers better compression efficiency and better performance (for example 30p instead of 24p).

Apple's oddball HLG + DoVi dynamic metadata approach is an interesting one, although HLG to SDR is still a weaker creative tool than native SDR.