CONVERTING A TONE CURVE FOR IMAGES WITH AN EXPANDED DYNAMIC RANGE Russian patent published in 2020 - IPC G06T5/00 

FIELD: computer equipment.

SUBSTANCE: converting an image from a first dynamic range to a second dynamic range is based on a function which includes two spline polynomials determined using three reference points and three slopes. First reference point is determined using black point levels from input and target output, second reference point is determined using white point levels from input and target output, and the third reference point is determined using halftone data for input and target output. Level of halftones of the target output is calculated adaptively based on the ideal conversion of 1 to 1 and by ensuring preservation of the input contrast in both shadows and glares.

EFFECT: technical result consists in improvement of accuracy of determination of tone curve for conversion of HDR-images for display.

19 cl, 1 tbl, 8 dwg