Patent Document ID: 9420145
Application ID: 14572093
Patent Status: 1

Claim One:
1. A method of processing an image, the method comprising: dividing an image into N zones; and for each respective zone of the N zones, calculating a normalized average luma value (YN avg ) for the respective zone as an average luma value of the zone normalized by a maximum luma value of the image, determining an exposure level for the respective zone, by determining that the exposure level is (i) over-exposure if YN avg is greater than an upper threshold, (ii) under-exposure if YN avg is less than a lower threshold, and (iii) normal exposure if YN avg is neither greater than the upper threshold nor less than the lower threshold, and setting parameters of a tone curve for the respective zone based on the determined exposure level; and for each respective pixel of multiple pixels of the image, applying the tone curve of each zone of M zones of the N zones to the respective pixel to yield M tone-mapped values, wherein M is equal to or less than N, weighting each M tone-mapped value with a weighting factor to yield M weighted tone-mapped values, and calculating a weighted-sum value for the respective pixel as a sum of the M weighted tone-mapped values.