# MATLAB: Making an image from extracted bit planes:

Image Processing Toolboxwatermarking

I'm sorry for repeat. But I put 'accepted answer' in last thread by mistake and I've not final answer yet, so… Here it is again. Sorry for inconvenience.
Hi, I'm new here. And beginner for MATLAB.
I've written a code for watermarking in spatial domain. I've applied the technique of replacing LSB of original image with watermark. Now, my question is, how to save these planes in a single image? It gives me error 'Matrix dimensions must match'… Kindly help…
B1 = bitget(A,1)*2^0; B2 = bitget(A,2)*2^1 ; B3 = bitget(A,3)*2^2 ; B4 = bitget(A,4)*2^3 ; B5 = bitget(A,5)*2^4 ; B6 = bitget(A,6)*2^5 ; B7 = bitget(A,7)*2^6 ; B8 = bitget(A,8)*2^7 ;
figure,subplot(3,3,1),imshow(B1); subplot(3,3,2),imshow(B2); subplot(3,3,3),imshow(B3); subplot(3,3,4),imshow(B4); subplot(3,3,5),imshow(B5); subplot(3,3,6),imshow(B6); subplot(3,3,7),imshow(B7); subplot(3,3,8),imshow(B8);
C1 = bitget(C,1)*2^0; C2 = bitget(C,2)*2^1 ; C3 = bitget(C,3)*2^2 ; C4 = bitget(C,4)*2^3 ; C5 = bitget(C,5)*2^4 ; C6 = bitget(C,6)*2^5 ; C7 = bitget(C,7)*2^6 ; C8 = bitget(C,8)*2^7 ;
figure,subplot(3,3,1),imshow(C1); subplot(3,3,2),imshow(C2); subplot(3,3,3),imshow(C3); subplot(3,3,4),imshow(C4); subplot(3,3,5),imshow(C5); subplot(3,3,6),imshow(C6); subplot(3,3,7),imshow(C7); subplot(3,3,8),imshow(C8);
M1 = bitget(C,8)*2^0; M2 = bitget(A,2)*2^1 ; M3 = bitget(A,3)*2^2 ; M4 = bitget(A,4)*2^3 ; M5 = bitget(A,5)*2^4 ; M6 = bitget(A,6)*2^5 ; M7 = bitget(A,7)*2^6 ; M8 = bitget(A,8)*2^7 ;
figure,subplot(3,3,1),imshow(M1); subplot(3,3,2),imshow(M2); subplot(3,3,3),imshow(M3); subplot(3,3,4),imshow(M4); subplot(3,3,5),imshow(M5); subplot(3,3,6),imshow(M6); subplot(3,3,7),imshow(M7); subplot(3,3,8),imshow(M8);
M=M1+M2+M3+M4+M5+M6+M7+M8; figure,imshow(M),title('Final Image');
___Here's the answer by 'Image Analyst', but I'm still getting the same error.
It's because your watermark is not the same size as your base image. Instead of your "M=…." line, replace it with this code:
[rowsC columnsC] = size(C) % Define location of final watermark. topRow = 10; leftColumn = 20; bottomRow = topRow + rowsC – 1; rightColumn = leftColumn + columnsC – 1; % Get an image as big as the original canvass = zeros(size(A), 'uint8'); canvass(topRow:bottomRow, leftColumn:rightColumn) = C8; % Now they're all the same size so you can add them. M = canvass +M2+M3+M4+M5+M6+M7+M8;___
Kindly help…