Patent ID: 11915392
Assignee: SHANGHAI LINKCHIP SEMICONDUCTOR TECHNOLOGY CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 2:
3. The image enhancement method according to claim 2, wherein the chrominance components include a U component and a V component, the edge preserving filtering is bilateral filtering, the step of performing edge preserving filtering on the low frequency sub-bands of the chrominance components according to the weight comprises:, U_LL
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where N is a current wavelet layer number, 1≤N≤Nmax, and N is a natural number, (x,y) is a coordinate of a pixel, (i,j) is an offset in a window, −WINN≤i,j≤WINN, WINN is a Gaussian kernel radius of the Nth layer, U_LLN(x, y) is a low frequency sub-band of a U component pixel (x,y) of the Nth layer, V_LLN(x, y) is a low frequency sub-band of a Y component pixel (x,y) of the Nth layer, U_LLN(x+i, y+j), V_LLN(x+1, y+j) are respectively pixel sets of the U, V component pixels U_LLN(x, y), V_LLN(x, y) taking the Gaussian kernel size WINN as the radius, WN(x+i, y+j) is a corresponding weight.