I was working on image steganography of lsb substitution using RGB image.I couldn't able to figure out what's wrong in the code. It is not showing an error.But,the answer is different while retrieving and codes are :
Embbeding code:
clc
c = imread('pout.tif');
c=imresize(c,[64 64],'nearest');
message = 'image';
message = strtrim(message);
m = length(message) * 8;
AsciiCode = uint8(messag e);
binaryString = transpose(dec2bin(AsciiCode,8));
binaryString = binaryString(:);
N = length(binaryString);
b = zeros(N,1);
for k = 1:N
if(binaryString(k) == '1')
b(k) = 1;
else
b(k) = 0;
end
end
s = c;
height = size(c,1);
width = size(c,2);
k = 1;
for i = 1 : height
for j = 1 : width
LSB = mod(double(c(i,j)), 2);
if (k>m || LSB == b(k))
s(i,j) = c(i,j);
else
if(LSB == 1)
s(i,j) = (c(i,j) - 1);
else
s(i,j) = (c(i,j) + 1);
end
k = k + 1;
end
end
end
imwrite(s,'msgimage.tif');
imshow(c)
retrieving_code:
clc
s = imread('msgimage.bmp');
height = size(s,1);
width = size(s,2);
m = 64;
k = 1;
for i = 1 : height
for j = 1 : width
if (k <= m)
b(k) = mod(double(s(i,j)),2);
k = k + 1;
end
end
end
binaryVector = b;
binValues = [ 128 64 32 16 8 4 2 1 ];
binaryVector = binaryVector(:);
if mod(length(binaryVector),8) ~= 0
error('Length of binary vector must be a multiple of 8.');
end
binMatrix = reshape(binaryVector,8,8);
textString = char(binValues*binMatrix);
disp(textString);
help please.
