Patent ID: 9654803
Date: 2017-05-16
CPC Classifications: G06T,H04N

Claim:
1. A method of pre-processing a pixel in a picture, said method comprising: obtaining an original linear luminance component value of said pixel in a third color space, the third color space comprising a linear XYZ color space, the original linear luminance component value being determined based on a linear color of said pixel in a first linear color space; and deriving a non-linear luma component value in a second non-linear color space for said pixel based on a first non-linear chroma component value in said second color space, a second non-linear chroma component value in said second color space and said original linear luminance component value in said third color space; wherein deriving said non-linear luma component value comprises deriving a non-linear luma component value in said second color space that minimizes a difference between said original linear luminance component value in said third color space and a linear luminance component value in said third color space determined based on said non-linear luma component value in said second color space, said first non-linear chroma component value in said second color space and said second non-linear chroma component value in said second color space.