MATLAB: How to combine bit map images to get back the original grey scale image

i have converted the grey scale image into 6 bit map images. i am using these 8 images as watermark inserting into the video. after extracting all these 8 images.Image Processing Toolbox

C=imread('cameraman.tif'); C1=bitget(C,1); figure, imshow(logical(C1));title('Bit plane 1'); C2=bitget(C,2); figure, imshow(logical(C2));title('Bit plane 2'); C3=bitget(C,3); figure, imshow(logical(C3));title('Bit plane 3'); C4=bitget(C,4); figure, imshow(logical(C4));title('Bit plane 4'); C5=bitget(C,5); figure, imshow(logical(C5));title('Bit plane 5'); C6=bitget(C,6); figure, imshow(logical(C6));title('Bit plane 6'); C7=bitget(C,7); figure, imshow(logical(C7));title('Bit plane 7'); C8=bitget(C,8); figure, imshow(logical(C8));title('Bit plane 8');

Best Answer

Multiply bit plane 7 by 2^7, bitplane 6 by 2^6, and so on. Then add them all up.

http://www.mathworks.com/matlabcentral/answers/13205#answer_18099

Related Solutions

MATLAB: Making an image from extracted bit planes:

It worked for me using the standard demo images moon.tif and cameraman.tif. For us to proceed now, you'd have to upload your images so we can figure out why my code didn't work for your images.

MATLAB: I had partitioned the image (‘cameraman.tif’ )into 8-bit map images ( C1, C2, C3, C4, C5, C6, C7, C8) but unable to rejoin to get back the original image ‘C’ as shown below in the related code in the Body Section.

The first thing where you've gone wrong is to create all these C* images. If you're numbering variables, you're doing something wrong. Matlab already has a very effective way of storing things with a numbering index, it's called a matrix or cell array. So:

 Cbit{1} = bitget(C, 1); figure, ...
 Cbit{2} = ...
 %etc

And, since you're now using a cell array, you can avoid retyping/ copy-pasting all this repeating code simply by replacing it with a loop:

Cbit = cell(1, 8);  %always a good idea to preallocate although in your case won't make a difference
for bit = 1:8
  Cbit{bit} = bitget(C, bit);  figure, imshow(logical(Cbit{bit})), title(sprintf('Bit plane %d', bit));
end

Isn't that easier?

As for putting the image back together, simply use the inverse operation. You use bitget to get the bits, use bitset to set them back:

newC = zeros(size(C), class(C));
for bit = 1:8 
   newC = bitset(newC, bit, Cbit{bit});
end

Another option to reconstruct that image is to do the arithmetic yourself. One of the many ways (in R2016):

newC = sum(cat(3, Cbit{:}) .* permute(2.^(0:7), [1 3 2]), 3)

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Related Solutions

MATLAB: Making an image from extracted bit planes:

MATLAB: I had partitioned the image (‘cameraman.tif’ )into 8-bit map images ( C1, C2, C3, C4, C5, C6, C7, C8) but unable to rejoin to get back the original image ‘C’ as shown below in the related code in the Body Section.

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