How to hide watermark of an image via MATLAB?

Hi, I am new in MATLAB, I have been given a code which hides the watermark image into the bit0 of the original image:

orig = imread('lennagray.bmp');
wm = imread('watermark.gif');
[h w] = size(orig);
subplot(121), imshow(orig);
subplot(122), imshow(wm, [0 1]);

img = bitand(orig, uint8(254*ones(w,h)));
img = img + wm;
imwrite(img, 'lennawm00.bmp');

I need to hide the watermark into bit5 instead of bit0. Can anyone help me out please?

Answer 1

[Sean de Wolski]

I think this blog entry (hint: and a utility linked in it) might interest you:

Steve's_Blog:image()