How to use Canny edge detector as a local edge detector?

I mean , i have this big matrix which i want to split to small part and for each part to find it's edges using Canny and in the end to return it to it's original size.

how can i do that?

[Image Analyst]

Why do you want to do that? Aren't all edges local already anyway? Do you expect any difference, except maybe for some boundary artifacts on the smaller subimage method?

Answer 1

[Sukuchha]

use blockproc