Crop the region

I wanted to know how to obtain the region inside the border. For example I am using the MRI liver image and I just want all the portions inside the liver. The other portions such as kidney, uterus and other things i do not require. I have obtained the border for the liver but its black inside the region.

Answer 1

[Image Analyst]

See here: http://iris.usc.edu/Vision-Notes/bibliography/contentsmedical.html#Medical%20Applications,%20CAT,%20MRI,%20Ultrasound,%20Heart%20Models,%20Brain%20Models

You need to do image segmentation. I have demos for that in my File Exchange: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

[Amishi]

Thanks a lot. This demo was really useful.

I have a query when i give my liver mri image and use the bwboundaries and plot i get all the regions with boundaries.

When i try using imcrop the sub image which i get is not the exact which is shown in boundary, it contains some extra portions other than which is in boundaries. May i know why this happens.

[Image Analyst]

That's because imcrop must take a rectangular region while boundaries do not have to be rectangular. You can mask out stuff outside the boundaries. I've posted demos on masking before - search for them or ask if you can't find any.