how can i run mfile on an image?

i download an mfile named exterma from here,which finds exterma points in an image,how can i use this mfile to find exterma points in my image?is there any link to explain it?

[Star Strider]

The function documentation should explain it.

What is the link to the function you downloaded?

[Joseph Cheng]

if it is the extrema function off the FEX the documentation page of the entry has it all.

http://www.mathworks.com/matlabcentral/fileexchange/12275-extrema-m--extrema2-m/content/extrema/extrema.m

and

http://www.mathworks.com/matlabcentral/fileexchange/12275-extrema-m--extrema2-m/content/extrema/extrema2.m

[sara]

I have 3 links for detecting exterma point,one of them is what you mentiond,when I put my image address instead of xy it gives me the error that (Undefined function 'extrema' for input arguments of type 'uint8'.).(I just write the address and rgb2gay) 2 other linkes gives me just numbers,hundreds of 0 and 1,.i want to detect exterma corners of my image,like top right,right top,buttom left,left buttom,...isn't it better if I use hit miss function,.there is an axample of finding right top corner of an image in Gonzales book,.i should just change the strl for each case.thank you these are 2 other links which gave me numbers http://www.mathworks.com/matlabcentral/fileexchange/45338-findextrema/content/findExtrema.m

http://www.mathworks.com/matlabcentral/fileexchange/41955-find-image-extrema