Patent ID: 11967051
Assignee: ARASHI VISION INC.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 4:
5. The method according to claim 1, wherein the performing the gradient operation on the target gradient image to obtain the target Laplacian image comprises:
calculating the Laplacian image according to four gradient information of the target gradient image by using a calculation formula (5):

L(u,v)=gx(u,v)−gxb(u,v)+gy(u,v)−gyb(u,v);  (5)

for the Laplacian image, adding a small component of a brightness value of the original image by using a calculation formula (6):, L
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            +
            
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                  ∑
                  
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                      I
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                  ⁢
                  
                    
                      M
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        ;
      
    
    
      
        (
        6
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wherein, N is a total number of images, Ii is the i-th original image, is a mask image of the i-th image, the pixel value is 1 when the pixel is effective pixel, otherwise the pixel value is 0; Mi ensures that for each pixel (u,v), only one of N images has the pixel value of 1, and the rest have the pixel value of 0.