Img1 = imread('peppers.png');
Img1=imresize(Img1,[256 256]);
f=figure;
imshow(Img1);
rect = getrect(f); %//select roi with mouse
Img1_roi = Img1( rect(2) : (rect(2)+rect(4)) , rect(1) : (rect(1)+rect(3)) , : ); %//store roi in matrix
Img2 = imread('coins.png');
Img2= imresize(Img2,[256 256]);
f=figure;
imshow(Img2);
rect = getrect(f); %//select roi with mouse
Img2_roi = Img2( rect(2) : (rect(2)+rect(4)) , rect(1) : (rect(1)+rect(3)) , : ); %//store roi in matrix
%//Plot
subplot(2,2,1)
imshow(Img1)
subplot(2,2,2)
imshow(Img2)
subplot(2,2,3)
imshow(Img1_roi)
subplot(2,2,4)