contour following in binary images

the function finds the contour pixels in a bw image.. the object is assumed to be white.

[knew,m,n]=contour_b_trial_2(a,row,col)
knew=contour image
m=contour background pixels
n=contour object pixels

ch=contour_code_2(m)
ch=contour code

[k8,m8]=eightneighbour(k,n)
k8=contour image containing eight neighbourhood
m8=contour pixels

[k4,m4]=fourneighbour2(k,n)
k4=contour image containing four neighbourhood
m4=contour pixels

press pause after each plot to continue