% grapple3.m applies median filters with succesively larger windows

G = imread('grapple.gif');           % read the .gif file
clf
subplot(3,3,1)
imshow(G,[0 1]);                     % display the image with 2 gray levels
title('Original image')
drawnow
for i=2:9,
  q = 2*i-1;                         % width of filter window
  G = medfilt2(G,[q q],'symmetric'); % use this size filter twice
  G = medfilt2(G,[q q],'symmetric');
  subplot(3,3,i)
  imshow(G,[0 1]);
  title(['After ' int2str(q) ' by ' int2str(q) ' median filter']);
  drawnow
end