MATLAB: Aligning overlapping images and averaging the overlap

Question

i have an empty matrix

canvas = uint8(zeros(10));

images are placed inside

image1=uint8(magic(3));

canvas(2:4,2:4)=image1;

a second image obviously overwrites the first

image2=uint8(magic(3));

canvas(3:5,3:5)=image2;

I would like to average the overlapping region

my attempt was to inspect each element in canvas to see if it was zero or non zero and then average each element(of subsequent images) one by one if it was non zero. sadly my code is really slow and doesn't work properly..

please help

Answer 1

I'm not quite sure what you want to do in the non-overlapping region, but if you want to leave the original images as they are, then you can do it like this:

canvas1 = uint8(zeros(10));
canvas2 = canvas1;
image1=uint8(magic(3));
canvas1(2:4,2:4)=image1;
image2=uint8(magic(3));
canvas2(3:5,3:5)=image2;
canvas = canvas1 + canvas2;
overlap = canvas1 & canvas2;
canvas(overlap) = canvas(overlap)/2;

I don't think this corresponds exactly to your code though. If you could say what the result in your example should be, it would be possible to be more certain of what to do.