Is there any way to make this code better?

Hi, I have this code that draws a rectangle onto an image. However, it is very slow for if I wish to draw multiple rectangles. Is there any better way to draw something onto an image?

function imret = image_dsquare( im, r1, c1, r2, c2, val )
    [imr imc] = size(im);
    imret = im;
    for r = r1:r2
        for c = c1:c2
            if r >= 1 && r <= imr && c >= 1 && c <= imc
                imret(r, c) = val;
            end
        end
    end
end

Answer 1

[Sean de Wolski]

imret(max(r1,1):min(r2,imr),max(c1,1):min(c2,imc)) = val;

[Qingyang]

Thanks, that did help a lot. But, is there any better (even faster) way of drawing points on an image?

[Sean de Wolski]

That is probably as fast as it's going to get for the code you have above...

Why is speed so important? How many time are you actually going to call this? Does it matter if one approach takes a few ten thousanths of a second longer?

[Qingyang]

Thanks for your help. I was calling this maybe >1000 times for each run. However, I did come up with another way to draw on the image that was much faster.