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2D discrete convolution and correlation

The neighborhood-weighted-sum operation, defined for a 2D image and kernel.

2D correlation, (I\star H)(x,y)=\sum_{i,j}I(x+i,y+j)H(i,j), and 2D convolution, (I*H)(x,y)=\sum_{i,j}I(x-i,y-j)H(i,j), both compute a weighted sum over a window of input pixels centered at (x,y), using the kernel H as weights.

See also

kernel neighborhood operation
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