Kernel "Laplacian" of size 5x5+2+2 with values from -4 to 4
Forming a output range from -24 to 24 (Zero-Summing)
 0:    -4    -1     0    -1    -4
 1:    -1     2     3     2    -1
 2:     0     3     4     3     0
 3:    -1     2     3     2    -1
 4:    -4    -1     0    -1    -4