Laplacian edge finders

laplace4(M) Returns the convolution of matrix M with a 3 x 3 Laplacian kernel. The kernel's center is 4.

laplace8(M) Returns the convolution of matrix M with a 3 x 3 Laplacian kernel. The kernel's center is 8.

laplace24(M) Returns the convolution of matrix M with a 5 x 5 Laplacian kernel. The kernel's center is 24.

Arguments:

• M is an image matrix.