how can I read and extract the 2 LSBs of every byte from the RGB image array ?

2 views (last 30 days)
i want to read the 2 LSbs of every byte for exaple i want to read (00) from this byte (11111100) for the whole of the image

Accepted Answer

yanqi liu
yanqi liu on 27 Dec 2021
clc; clear all; close all;
img = imread('cameraman.tif');
img2 = blockproc(img,[1 1],@sp);
figure; imshowpair(img,img2,'montage')
function y=sp(x)
% every byte
x2 = dec2bin(x.data);
% 2 LSB of every byte
y=bin2dec(x2(end-1:end));
end

More Answers (1)

Voss
Voss on 26 Dec 2021
One way is to read the data as bytes (type uint8) like usual, then the 2 LSBs are the remainder after dividing by 4, e.g.:
b = uint8(0:255)
b = 1×256
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
r = rem(b,4)
r = 1×256
0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 1
s = dec2bin(r)
s = 256×2 char array
'00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11' '00' '01' '10' '11'
a = s-'0'
a = 256×2
0 0 0 1 1 0 1 1 0 0 0 1 1 0 1 1 0 0 0 1

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!