Question

The objective is to combine 3 equal sized images(512*512*3) into a resultant image E whose size is r= 1536 c =512 d=3

img1=imread('pic1.jpg');
img2=imread('pic2.jpg');
img3=imread('pic3.jpg');

figure;
E = [img1; img2; img3];
imshow(E);
figure;
subplot(1,3,1);
E1 = E(:,img1,img2);
imshow(E1);
E2=E(img1,:,img3);
sublot(1,3,2);
imshow(E2);
E3=E(img1,img2,:);
sublot(1,3,3);
imshow(E3);

1. This results into error

   ??? Subscript indices must either be real positive integers or logicals.

   Error in ==> combined_img at 11
   E1 = E(:,img1,img2);

Please help to resolve this .

Answer 1

The error is exactly what it says it is: the indices must be integers or logicals. When you try to index using img1, it’s likely that it contains non-integers, which throws the error. Here’s what you should do:

E=[img1; img2; img3];%#combine the images
E1=E(1:512,:,:);
E2=E(513:1024,:,:);
E3=E(1025:end,:,:);

You can also do it more elegantly as

imgDim=size(img1,1);%# since they're all equal dimensions, we'll need just one.
imgCell=mat2cell(E,[imgDim,imgDim,imgDim],imgDim,3);%# create a cell
[E1, E2, E3]=deal(imgCell{:});%#distribute contents of cell