matlab coding for 3*3 sliding window to remove noise from digital image

our project deals with removal of random valued impulse noise from a 256*256 digital image using medium filtering.The window has to slide through the entire image.each 3*3 window is sorted and the median is calculated.then the middle element is replaced with the pixel.we are fiding difficulty in sliding it.plz help us out.开发者_如何转开发.

To perform a median filter with a 3-by-3 sliding window, you can use MEDFILT2 like so:

filteredImage = medfilt2(yourImage,[3 3])

Take a look at the function nlfilter, it is an easy way to do what you need.

http://www.mathworks.com/help/toolbox/images/ref/nlfilter.html

For the future, please do a bit of research and try to do something yourself before asking here.