hi all... i am writing a program to histogram equalize particular bit planes in an image..but i am getting an error in the 1st bit plane..Attempted to access a(241,320); index out of bounds because size(a)=[240,320]. Error in BITPLANE (line 59)

clc;
close all;
clear all;

a = imread('F:\TEST PICTURES\car.jpg');
a = rgb2gray(a);
[m n] = size(a);
% to extract 7th bit plane
for i = 1:m
    for j = 1:n
        b7(i,j) = bitand(a(i,j),128);
       end
end
b7o = histeq(b7);

%to extract 6th bit plane
for i = 1:m
    for j = 1:n
        b6(i,j) = bitand(a(i,j),64);
    end
end
b6o = histeq(b6);

%to extract 5th bit plane
for i = 1:m
    for j = 1:n
        b5(i,j) = bitand(a(i,j),32);
    end
end
b5o = histeq(b5);

%to extract 4th bit plane
for i = 1:m
    for j = 1:n
        b4(i,j) = bitand(a(i,j),16);
    end
end
b4o = histeq(b4);

%to extract 3rd bit plane
for i = 1:m
    for j = 1:n
        b3(i,j) = bitand(a(i,j),8);
    end
end
b3o = histeq(b3);

%to extract 2nd bit plane
for i = 1:m
    for j = 1:n
        b2(i,j) = bitand(a(i,j),4);
    end
end
b2o = histeq(b2);

%to extract 1st bit plane
for i = 1:m
    for i = 1:n
        b1(i,j) = bitand(a(i,j),2);
    end
end
b1o = histeq(b1);

%to extract 0th bit plane
for i = 1:m
    for j = 1:n
        b0(i,j) = bitand(a(i,j),1);
    end
end
b0o = histeq(b0);
cc = 2*(2*(2*(2*(2*(2*(2*b7o+b6o)+b5o)+b4o)+b3o)+b2o)+b1o)+b0o;

figure, imshow(cc)

Answer 1

[Walter Roberson]

You miscoded

   for i = 1:n

instead of

   for j = 1:n

[vishwas h s]

thanks Mr.Walter ..

[Maneesh Mande]

Sir..what if we want to break Cb components on an YCbCr format image in to different bit planes after we break Y,Cb and Cr components seperately...like:

C=imread('Sample.png'); YCbCr=rgb2ycbcr(C); Y=YCbCr(:,:,1); Cb=YCbCr(:,:,2); Cr=YCbCr(:,:,3);

[Walter Roberson]

Then go ahead and do that. bitget does not care how how the bits were derived.

[Maneesh Mande]

Thank you Mr.Walter

[Maneesh Mande]

Will the same above code work for breaking LH and HH sub bands of the Cb component in to bit planes?

[Walter Roberson]

LH and HH is typically notation for floating point coefficients associated with wavelets. If that is the case for you then bitget will not work. But if your LH and HH are integers it will (might need to be nonnegative)

[Maneesh Mande]

They are floating point as you suspected and contains negative values too...In this case how do I break them in to bit planes?