UltraGrid, macOS, color accuracy

Flame Tools and Tech
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If you have been using UltraGrid on macOS with HEVC or ProRes VideoToolBox compression, it has been converting every incoming signal into 8bit, even if it was originally 10/12 bit.

I worked with them, and they have fixed this last night in the latest continuous build, but I have not validated the results.

With HEVC Video Toolbox, the best they can do is 10bit YCbCr 4:2:2. I believe it is a limitation of FFMPEG.

With ProRes they now use 16bit YUV 4:4:4.

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@ALan - excellent community service as always brother.

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So crazy–I actually noticed this yesterday on 1.9. I was setting up the UG scripts from @john-geehreng and checking the output with scopes on the home setup. The source material had hyper saturated backgrounds with subtle grads and I could see the quantization. Switched over to SDI or NDI and it was basically gone.

Looking into this was on my to-do list for today. Cheers @ALan

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…and literally an audience of me

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relavent GitHub issues here:

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@cnoellert if you could verify the latest UG on the scope for me, would be much appreciated. \ I re-purposed that Mac for something else, and don’t have convenient access right now.

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When I’m back in the states I’ll definitely check it out. Ran out of time before leaving…