clc; clear all; close all;
function out_put =
btc_image(in_put,block_size)
X=imread('rice.png');
Y=imfinfo('rice.png');
K=input('Enter the block size');
X1=double(X);
y1=size(X);
n=y1(1);
m=y1(2);
k=1;l=1;
if (Y.ColorType=='grayscale')
% IMAGE ENCODING
% FOR GRAY SCALE IMAGES
subplot(131),imshow(X),title('ORIGINAL');
disp('K=');
disp(K);
for i=1:K:n
for
j=1:K:m
tmp([1:K],[1:K])=X1([i:i+(K-1)],[j:j+(K-1)]);
mn=mean(mean(tmp));
tmp1([i:i+(K-1)],[j:j+(K-1)])=tmp>mn;
Lsmat=(tmp<mn);
Mrmat=(tmp>=mn);
Lsmn=sum(sum(Lsmat));
Mrmn=sum(sum(Mrmat));
Mu(k)=sum(sum(Lsmat.*tmp))/(Lsmn+.5);k=k+1;
Mi(l)=sum(sum(Mrmat.*tmp))/Mrmn;l=l+1;
end
end
subplot(132),imshow(tmp1);title('ENCODED');
% IMAGE DECODING
k=1;l=1;
for i=1:K:n
for
j=1:K:m
tmp21([1:K],[1:K])=tmp1([i:i+(K-1)],[j:j+(K-1)]);
tmp22=(tmp21*round(Mu(k)));k=k+1;
tmp21=((tmp21==0)*round(Mi(l)));l=l+1;
tmp21=tmp21+tmp22;
out_put([i:i+(K-1)],[j:j+(K-1)])=tmp21;
end
end
subplot(133),imshow(uint8(out_put));title('DECODED');
% FOR COLORED IMAGES
elseif (Y.ColorType=='truecolor')
R=X(:,:,1);
G=X(:,:,2);
B=X(:,:,3);
%
IMAGE ENCODING
subplot(131),imshow(X),title('ORIGINAL');
for b=1:3
for
i=1:K:n
for j=1:K:m
tmp([1:K],[1:K])=X1([i:i+(K-1)],[j:j+(K-1)],b);
mn=mean(mean(tmp));
tmp1([i:i+(K-1)],[j:j+(K-1)],b)=tmp>mn;
Lsmat=(tmp<mn);
Mrmat=(tmp>=mn);
Lsmn=sum(sum(Lsmat));
Mrmn=sum(sum(Mrmat));
Mu(b,k)=sum(sum(Lsmat.*tmp))/(Lsmn+.5);k=k+1;
Mi(b,l)=sum(sum(Mrmat.*tmp))/Mrmn;l=l+1;
end
end
end
subplot(132),imshow(tmp1);title('ENCODED');
% IMAGE DECODING
k=1;l=1;
for b=1:3
for
i=1:K:n
for j=1:K:m
tmp21([1:K],[1:K])=tmp1([i:i+(K-1)],[j:j+(K-1)]);
tmp22=(tmp21*round(Mu(b,k)));k=k+1;
tmp21=((tmp21==0)*round(Mi(b,l)));l=l+1;
tmp21=tmp21+tmp22;
out_put([i:i+(K-1)],[j:j+(K-1)],b)=tmp21;
end
end
end
subplot(133),
imshow(uint8(out_put));
title('DECODED');
else
errordlg('IMAGE TYPE NOT SUPPORTED');
end
