How can I prevent moving ROI out of the image edges?

I have a Region Of Interest (ROI) on an image. Please see the following code:

a=imread('rice.png'); I=imshow (a); e = imellipse(gca,[]);

The ROI can be moved on the image by mouse dragging. I want that the ROI cannot be able to move out of the image, and be stopped when its bounds reach to the image edges. I would be much appreciated it if you could help me for resolving this problem. Thank you very much

Answer 1

[Image Analyst]

Did you happen to look at the help for imellipse and see the very first example:

figure, imshow('cameraman.tif');
h = imellipse(gca, [10 10 100 100]);
addNewPositionCallback(h,@(p) title(mat2str(p,3)));
fcn = makeConstrainToRectFcn('imellipse',get(gca,'XLim'),get(gca,'YLim'));
setPositionConstraintFcn(h,fcn);

Answer 2

[azim]

Thank you