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Old 26th June 2013, 23:14   #25  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by IanB View Post
From what I understand Sony use the 1-15 and 241-254 chroma values to represent higher saturation colours. When you do the normal YUV->RGB translation you can end up with normalised colour values less then 0.0 or greater than 1.0, normal decoders clamp these values, advanced decoders map these values into a wider gamut colour space. The luma range is still 16-235.
That makes sense. But if chroma is getting clamped at those values, I worry we'll see posterization of chroma levels when the extended colors get clamped. A gradient of "very red" could turn into a flat area of just red without any detail. If there is some texture in the luma channel that might mask things, but still. It seems like it would be hard to make a "best of both worlds" encode like this.
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