Image segmentation using Marr Hilderth Filter

The code compute the edge map of a grayscale image using Marr Hilderth Filter

The code is divided into following sections:

1. Filter the input image with an nxn Gaussian low-pass filter

2. Compute the Laplacian of the image resulting from step 1 using
a desirable mask (for instance 3x3)

3. Find the zero crossing of the image from step 2.

Running the code:

[Ioutput]= marrfilter(I);