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Re: Re: Digi Beta versus D1

Phil Mendelson wrote:
>The color space conversion loss described has very little to do with the
>fact that it's 8 bits.  What Charles Poynton is describing is the bandwidth
>reduction that occurs from full bandwidth RGB to 4:2:2 Y,Pb,Pr.

That is not correct. The color space loss occurs when converting between
R'G'B' and 4:4:4 Y'CbCr with the same bit depth. This is what Mr. Poynton
describes in his whitepaper 'Merging computing with studio video: Converting
between R'G'B' and 4:2:2', and it is a fact that can easily be proven.

The 4:2:2 subsampling reduces the spatial color resolution further, this
reduction is of course the same for both 8 bits and 10 bits Y'CbCr.

Thomas Lund

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