Shannon Edge Detector for Grayscale Images

This is an edge detector for grayscale images based on the Shannon Entropy measure for biodiversity.

The Shannon algorithm runs an edge detector method using a Shannon Entropy measure. The .zip folder contains three files, the main file, which is the Shannon Algorithm, an edge detector file and a threshold file. You will need all three files.
To edge detect a gray scale image, input the file name into the main file and click run.

A Shannon entropy-based edge detector is a new method, inspired by biodiversity measures.

I hope you find it useful. Below is a snippet of code from the Edge Detector procedure. It utilizes a 3x3 window.

% Edge Detector
function [g]=EdgeDetector_procedure(f);
[row column]=size(f);
g=f;
m = 3; n = 3; a0 = (m-1)/2; b0 = (n-1)/2;
for y = b0+1 : column-b0;
for x = a0+1 : row-a0;
sum1 = 0;
for k=-b0:b0;
for j=-a0:a0;
if ( f(x,y) == f (x+j,y+k) ) sum1=sum1+1; end;
end;
end;
if ( sum1>6 ) g(x,y)=0; else g(x,y)=1; end;
end;
end;