how can i set a croped squares values in an image to zero?

i want to remove a cropped square out of my image,?(the image without that cropped region),when i use imsubtract,it says they should be in same size,is it possible to give the value 0 to the cropped square instead?

Answer 1

[Image Analyst]

"remove a cropped square out of my image" - what does that mean? You can't remove it. Images must remain rectangular. You can't just remove them and have nothing/emptiness there. There has to be something there, even if it's just NaN values.

If you want to set some rectangular region to zero in a gray scale image, you can do this:

grayImage(row1:row2, col1:col2) = 0;

You can also set a non-rectangular region(s) to zero if you have a binary image where pixels are "true" if you want them to be set to zero, and false if you want them to remain untouched:

grayImage(mask) = 0;

[sara]

thank you very much,it worked so greate,it was part of the image which had bad effect on my segmentation.thank you,.