How to impose a window centered on each pixel location in an image in MATLAB?

I have an impulse affected noisy image of size 256*256. I have to detect those noise pixels. I want to impose a 11*11 window centered on current pixel and find the maximum (Smax) and minimun (Smin) value within the window. After that, I want to create a binary matrix (R) containing zero values for noisy and ones for noise-free pixels using thresholding.

where, R(i,j)=0, if difference between intensity value of pixel at location (i,j) and Smax is less than or equal to a threshold (T=10).