encrypting a dicom image?

i have the following code for encryption and decryption of .tif image. please help me to modify the samee for dicom images. when running with dicom following error is displayed as Error using ==> bitxor Inputs must be unsigned integers of the same class or scalar doubles.

Error in ==> processing at 16
        proImage(ind1,ind2) = bitxor(Img(ind1,ind2),Fkey(ind1,ind2));

code

main function

clc;
close all;
clear all;
Img=imread('cameraman.tif');
%figure,imshow(Img);
%Img = dicomread('188.dcm');
figure,imshow(Img,[])
    %figure,imshow(Img)
    title('input image');
     [n m k] = size(Img);
  key = keyge(n*m);
  EncImg = processing(Img,key);
  figure,imshow(EncImg)
  title('ecrypted');
imwrite(EncImg,'Encoded.jpg','jpg');
dec= processing(EncImg,key);
figure,imshow(dec)
title('decoded');

processing function

function [proImageOut] = processing(ImgInp,key)

[n m k] = size(ImgInp);
% key =cell2mat(struct2cell( load('key5.mat')));
% key = keyGen(n*m);
for ind = 1 : m    
    Fkey(:,ind) = key((1+(ind-1)*n) : (((ind-1)*n)+n));
end
len = n;
bre = m;
for ind = 1 : k
    Img = ImgInp(:,:,ind);
for ind1 = 1 : len
    for ind2 = 1 : bre        
        proImage(ind1,ind2) = bitxor(Img(ind1,ind2),Fkey(ind1,ind2));        
    end
end
proImageOut(:,:,ind) = proImage(:,:,1);
end
% figure,imshow(proImageOut);
return

   key

function [key] = key(n)
n = n*8;
% n = 2048*2048*16;
% n = 24 * 24 * 8;
bin_x = zeros(n,1,'uint8');
r = 3.9999998;
bin_x_N_Minus_1 =  0.300001;
x_N = 0;
tic
for ind = 2 : n
    x_N = 1 - 2* bin_x_N_Minus_1 * bin_x_N_Minus_1;    
     if (x_N > 0.0)
        bin_x(ind-1) = 1;
    end 
     bin_x_N_Minus_1 =  x_N;

end
toc
% save bin_sec bin_x;
t = uint8(0);
key = zeros(n/8,1,'uint8');
for ind1 = 1 : n/8

      for ind2 = 1 : 8
      key(ind1) = key(ind1) + bin_x(ind2*ind1)* 2 ^ (ind2-1);
      end

end

Answer 1

[Walter Roberson]

What does

dicominfo('188.dcm')

show for BitDepth ? I suspect you will find that it returns 16 for your file -- that is, that your DICOM image is uint16() where your code is expecting it will be uint8(). You will need to decide how you want to handle the situation.

[uthara ravi]

how can i convert the same?

[Walter Roberson]

Replace

for ind = 1 : m    
    Fkey(:,ind) = key((1+(ind-1)*n) : (((ind-1)*n)+n));
end

with

for ind = 1 : m    
    Fkey(:,ind) = cast( key((1+(ind-1)*n) : (((ind-1)*n)+n)), class(ImgInp) );
end