HOW TO READ THE VALUES IN PARTICULAR BLOCK WHEN THE IMAGE IS CONVERTED INTO CELLS BY USING MAT2CELL

clear all;

im=imread(uigetfile('*.*'));

im=imresize(im,[200 200]);

im=mat2cell(im,[50 50 50 50],[25 25 25 25 25 25 25 25],3);

.i have taken the rgb image.now i have to read the first block i.e.,50 rows, 25 columns.how to seperately read the first block for adding another image to the first block of same size

Answer 1

[Image Analyst]

Just use a nested for loop

[rows, columns] = size(im);
for col = 1 : columns
  for row = 1 : rows
    thisBlock = im{row, col];
    % Now do whatever you want with this 2D array of numbers.
    % For example
    thisBlock = (double(thisBlock) + double(referenceBlock) / 2; % or whatever...
  end
end

[sonam s]

clear all;

im=imread(uigetfile('*.*'));

im=imresize(im,[200 200]);

[x y z]=size(im);

%generate the carrier image

k=1;

for i=1:200

for j=1:200

carry(i,j)=b(k);

k=k+1;

   if(k>length(b))

    k=1;

    end;

end;

end;

figure;

imshow(uint8(carry));

carry=imresize(carry,[50 25]);

title('carrier image')

im=mat2cell(im,[50 50 50 50],[25 25 25 25 25 25 25 25],3);

for col = 1 : 25

for row = 1 : 50

    thisBlock = im(row, col);

    im=double(im(row,col))+double(carry);

end;

end;

i have written the above code.the carrier image is 2-d text image.this carrier i want to add to the blocks seperately.i have tried the code given by you but it is encountered with an error.please help

[Image Analyst]

Here's some help on resolving the error: http://blogs.mathworks.com/videos/2012/07/03/debugging-in-matlab/

Once you view that, you'll probably notice that you are overwriting your whole cell array with the contents of just one block of it added to the carry image. So now you've destroyed im. It's no longer a cell array!