Quote:
Originally Posted by Blue_MiSfit
Interesting. So what you're saying is that the output of profile 5 is effectively 10 bit, even though Dolby says the shaping of 12+ bit RGB input into 10 bit IPT lets them preserve more precision during playback?
|
Yes. IPTs benefit is constant luminance. With YCbCr at high nit saturated colors, you get visible noise in the image. This all goes away in IPT. Netflix and others have developed techniques to try and reduce the noise, but not nearly as effective as IPT. After encoding, they modify the analyze the Y channel and alter it for cleaner results and then re-encode.
Have you ever noticed the dark transition between colors on a color bars test pattern? That is due to non-constant luminance of YCbCr. IPT does not suffer from this either.
PQ, in general, is at least two bits more efficient than gamma. 12-bit PQ is like 15-bit gamma.