Quote:
Originally Posted by groucho86
I created a 16bit TIFF SMPTE bars out of Resolve. ProRes 4444 full range exported out of Resolve and out of Baselight exhibit similar issues (when imported back into Resolve/Baselight), whereas legal range matches much more closely the RGB TIFF source.
Beyond legacy/compatibility, there's *something* that makes legal range ProRes 4444 technically correct. But I can't fully articulate it.
I plan on trying other Finishing/Broadcast softwares that allow setting data levels. I know Premiere/Media Encoder doesn't. Not sure about Apple Compressor. I will test Transkoder.
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Prores is almost always limited range, most programs are setup to handle it like that, so I'd use it like that - for compatibility - if you're "forced" to use prores
But if color was vitally important, and I was starting with 12bit RGB, I'd use an RGB format, such as EXR or 16bit PNG, or some +2 or higher bit depth YUV format (not sure of any compatible in resolve) You're only testing a handful of values with colorbars - what about the 68 trillion other colors ?
(2^12 * 2^12 * 2^12 = )
Math wise , RGB to YUV limited range round trip (vs YUV full range) will have more expected errors (on all colors, not just a few bars). Full range would preserve more unique colors of the source, if it's handled correctly (maybe try HEVC, since it supports 12bit, full range). In the 8bit full vs limited case it was about ~1.35 million more colors or ~1.49x more accurate unique colors for full range YUV .
To put it another way, you 're potentially losing about 83% of the unique colors of the source by limited range YUV at the same bit depth. But that was only 8bit ~16.7M colors. Too large to test 12bit. If you assume a similar trend at 12bit and ratio for scaling, it's still a significant difference in color accuracy in terms of unique colors
You can see some of the tests here, I don't think I posted the full range one
https://forum.doom9.org/showthread.php?t=183816
"identify" -format "%k" 8bitroundtrip.png
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~14M unique colors for typical 8bit RGB=>YUV=>RGB round trip (no subsampling) are lost !!
ConvertToYV24(matrix="rec709")
ConvertToRGB24(matrix="rec709")
full range round trip preserves more colors
ConvertToYV24(matrix="pc.709")
ConvertToRGB24(matrix="pc.709")
"identify" -format "%k" 8bitroundtrip_fullrange.png
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