View Single Post
Old 12th May 2016, 19:01   #37923  |  Link
Ver Greeneyes
Registered User
 
Join Date: May 2012
Posts: 447
Quote:
Originally Posted by omarank View Post
“The hardware lut's only have 256 slots for indexing by a 8 bpc framebuffer. In 10 bpc scanout modes, framebuffer color values would get truncated to their 8 msb's, thereby losing the extra precision afforded by a 10 bpc framebuffer.
To retain full precision, bypass the hw lut in 10 bpc scanout mode.”


I do use 10 bit output in madVR on my AMD system, and reading this made me shiver.
If that's true it sucks; they should be linearly interpolating between values when the bit depth is higher than the number of entries in the LUT. Still, if they have to bypass it altogether, then it doesn't matter what values are in the LUT - and filling the LUT from 0 to 65535 is still more correct than only setting the 8 high bits of each entry.
Ver Greeneyes is offline   Reply With Quote