How to extract 24 binary images from one RGB image which is of 24-bit/pixel color depth?

How to extract 24 binary images from one RGB image which is of 24-bit/pixel color depth in matlab ?

Answer 1

[David Young]

Try this:

% example rgb 24-bit image
img = imread('peppers.png');

% Make the binary array array corresponding to each bit
% and store it in a element of a cell array. bitarrays{1} has
% bit 1 for the r band, bitarrays{9} has bit 1 for the g band,
% bitarrays{24} has bit 8 for the b band, etc.
bitarrays = cell(1, 24);   % allocate cell array
for b = 1:24
  band = floor((b-1)/8) + 1;
  bitinband = b - 8*(band-1);
  bitarrays{b} = bitget(img(:,:,band), bitinband);
end

To see if the results look reasonable, display each image in turn:

for b = 1:24
  imshow(bitarrays{b}, []);
  pause;
end

One question though: why do you want to do this? I can't think of a reason why it would be useful, and if you would like to say what the underlying problem is, it may be that someone can suggest a much better way to tackle it.

Answer 2

[Image Analyst]

David's answer looks good. By the way, I also answered in your duplicate post: http://www.mathworks.com/matlabcentral/answers/223883-how-to-get-each-plane-of-a-24-bit-plane-image#answer_189718