How to find the volume of a region in a segmented image?

Hi, I segmented an MR image and have 3 regions, backgound with pixel value of 0, gray matter with pixel value of 1 and white matter of pixel value of 2. How can I get the volume of each of those regions?

Answer 1

[Matt J]

stats = regionprops3(segmentationMap,'Volume')

[ma_thal]

Thank you sir. However I'm not allowed to use this function :(

[Image Analyst]

Why not? Why prevent yourself from using a built-in function? Your post is not labeled as homework, which is usually the reason, so why not use it?

I was going to assume that you had 3 binary images, one for each segmentation that you want to do (background, gray matter, white matter) and that you could simply use nnz() on each binary image, but unfortunately you probably won't let yourself use nnz() either.

To find out what you can use, read this:

What can be programmed "without any built-in functions" ? - MATLAB Answers - MATLAB Central

[ma_thal]

Yes! it is homework, I'm new here so I didn't know I had to put that, I'm sorry..

Thank you for you idea. And I will check that link!