Help in DCT watermark embedding process

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Yasir 2013-2-23

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https://ww2.mathworks.cn/matlabcentral/answers/64668-help-in-dct-watermark-embedding-process

hi everyone, i got confuse regarding of this approach of watermark and still now i can't get it clearly therefor i make a post hopeful someone help me the required : 1- the steps of embedding process 2- Matlab script

Many Thanks

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Walter Roberson 2013-2-23

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https://ww2.mathworks.cn/matlabcentral/answers/64668-help-in-dct-watermark-embedding-process#answer_76251

http://www.mathworks.co.uk/matlabcentral/answers/27372-watermarking

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Walter Roberson 2013-2-23

Read Image Analyst's watermarking demo.

Yasir 2013-2-26

编辑：Yasir 2013-2-26

在 MATLAB Online 中打开

hi Walter,plz your help to finilize it Kindly i tried the below code to implement it but seems no thing am working in Cox DCT approach depend to forumla ti=ti+atixi, a=0.1

[fname pthname]=uigetfile('*.jpg;*.png;*.tif;*bmp','Select the Asset Image'); %select image
I=imread([pthname fname]);
origy=rgb2gray(I);
origdct=dct2(origy);
[rows cols]=size(origdct);
imglen=rows*cols;
origrddct=reshape(origdct, 1, imglen);
origs=sort(origrddct,'descend');%re-ordering all the absolute values
wmsz=2223; %watermark size
W=randn(1,wmsz);%generate a Gaussian spread spectrum noise 
%find the index of largest coffiencent
for k=1:wmsz
for i=1:imglen
if (origs(k)==origrddct(i))
    m(k)=i;
    display(i);
end 
end
end
%embedded formula
for j=1 :wmsz
    origsn(j)=((origs(j)  * 1)+ (0.3*origs(j)* W(j)));
end
for n=1: wmsz-1
    for f=1:imglen
    if (f == m(n) )
       origrddct(f)=origsn(n); 
    end
    end
end
mx=reshape(origrddct,rows,cols);
oridctx=idct2(mx);
figure , imshow(oridctx);
figure,imshow(origy);