US 12,388,964 B2
Method and apparatus for obtaining a mapping curve parameter
Weiwei Xu, Hangzhou (CN); Quanhe Yu, Beijing (CN); Hu Chen, Munich (DE); and Yichuan Wang, Beijing (CN)
Assigned to HUAWEI TECHNOLOGIES CO., LTD., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Guangdong (CN)
Filed on Oct. 28, 2022, as Appl. No. 17/976,426.
Application 17/976,426 is a continuation of application No. PCT/CN2021/088679, filed on Apr. 21, 2021.
Claims priority of application No. 202010366684.2 (CN), filed on Apr. 30, 2020.
Prior Publication US 2023/0042923 A1, Feb. 9, 2023
Int. Cl. H04N 9/77 (2006.01); G06T 5/92 (2024.01)
CPC H04N 9/77 (2013.01) [G06T 5/92 (2024.01); G06T 2207/20208 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for obtaining a mapping curve parameter, comprising:
obtaining a first mapping curve parameter set and first maximum target system display luminance, wherein the first mapping curve parameter set corresponds to the first maximum target system display luminance, and the first mapping curve parameter set comprises one or more parameters related to a mapping curve;
obtaining a display luminance parameter set that comprises maximum display luminance and/or minimum display luminance of a display device;
obtaining an adjustment coefficient set that comprises one or more adjustment coefficients that correspond to the one or more parameters in the first mapping curve parameter set; and
adjusting the one or more parameters in the first mapping curve parameter set based on the display luminance parameter set, the first maximum target system display luminance, and the adjustment coefficient set to obtain a second mapping curve parameter set that comprises one or more adjusted parameters;
wherein before the adjusting the one or more parameters in the first mapping curve parameter set based on the display luminance parameter set, the first maximum target system display luminance, and the adjustment coefficient set to obtain the second mapping curve parameter set, the method further comprises:
obtaining one or more of maximum luminance, minimum luminance, an average value, and a variation range of to-be-displayed content; and obtaining an intermediate value of a first parameter based on one or more of the maximum display luminance, the minimum display luminance, the maximum luminance, the minimum luminance, the average value, and the variation range, wherein the first parameter is any parameter in the first mapping curve parameter set; and
the adjusting the one or more parameters in the first mapping curve parameter set based on the display luminance parameter set, the first maximum target system display luminance, and the adjustment coefficient set to obtain the second mapping curve parameter set comprises:
calculating an adjusted first parameter according to formula (1), wherein the adjusted first parameter belongs to the second mapping curve parameter set:
Pa=(1−w)×Pb+w×Pm  (1)
wherein Pa represents the adjusted first parameter, Pb represents the first parameter, and

OG Complex Work Unit Math
 or

OG Complex Work Unit Math
 wherein PΔ represents an adjustment coefficient corresponding to the first parameter, MaxDisplay represents the maximum display luminance, MTPL represents the first maximum target system display luminance, N represents an adjustment control parameter, M represents a preset luminance value, and Pm represents the intermediate value of the first parameter.