Re:Gamma error in picture scaling
by AstralStorm on Tuesday January 08, 2019 @03:09AM
(#18854085)
You're not running a multi MB image but a small block thereof. Not that 5-6KiB LUT matters, but the extra conditional multiply ops or power or logarithm function evaluations do.
Latter are need a few MACs for a good approximation (at least 12 bit precise, preferably 16 bit - like 5th order polynomial), former have masks, worse for SIMD.
At least the instruction cache is barely affected, which would not be the case for a math library function.