Matlab中512x512图像中的示例8x8补丁

Question

I would like to randomly sample an 8x8 patch from an image that is of size 512x512. Is there a good (a quick and easy) way to do this in Matlab? All I want is an 8x8 matrix that was taken from the image. And I each 8x8 block in the image to be equally likely.

Answer 1

Say you have loaded the image using imread into a variable called im you can then do this:

r_X = randi(512-8);
r_Y = randi(512-8);
im_rand = im(r_X:r_X+8, r_Y:r_Y+8);

im_rand will contain an 8x8 section of your image starting from a corner generated randomly.