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Old 4th January 2019, 20:38   #6599  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by asarian View Post
Wonderful!

If I understood the process right, I'm most interested in 'Profile 8.2 single layer with SDR compatibility' myself, as any extra layer that can be used for a better HDR->SDR conversion, will be very welcome.
It wouldn't be any HDR->SDR conversion. The base layer would just be the SDR. I don't know of any real-world use of Profile 8.2, but I imagine it would be mainly used to take SDR sources and add metadata for how it should be enhanced for HDR. It is probably possible to derive profile 8.2 from an HDR DoVi master. But I don't know if full HDR dynamic range could be reconstructed without an actual secondary media layer, or a metadata layer with LOTS of spatial tagging.

Quote:
Bit off-topic, perhaps, but I wouldn't mind seeing DV SDR layer info getting added to x264 too, one day (after all, x264 has always been predominantly about 8-bit).
H.264 Dolby Vision was certainly used a bunch in early days. But I don't know why anyone would use it today; all consumer products I can think of that can display Dolby Vision have HEVC decoders.

But encoding isn't the hard part. The hard part is the shaping, inverse tone mapping, and metadata generation. Profile 8.1 is only easy because uncompressed HDR-10 is pretty much the raw format of a DoVi master (plus metadata). x26? doesn't even attempt to implement the complex tech required to do a good job converting between color volumes.
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