{"id":2133,"date":"2017-02-23T23:30:00","date_gmt":"2017-02-23T15:30:00","guid":{"rendered":"http:\/\/www.zuola.com\/weblog\/2017\/02\/2133.htm"},"modified":"2017-02-23T23:30:00","modified_gmt":"2017-02-23T15:30:00","slug":"%e6%88%91%e5%9c%a8%e7%a0%94%e7%a9%b6%e5%a6%82%e4%bd%95%e5%af%b9%e5%9b%be%e5%83%8f%e8%bf%9b%e8%a1%8c%e4%ba%8c%e7%bb%b4%e5%bf%ab%e9%80%9f%e5%82%85%e9%87%8c%e5%8f%b6%e5%8f%98%e6%8d%a2%ef%bc%8c%e6%b1%82","status":"publish","type":"post","link":"https:\/\/www.zuola.com\/weblog\/2017\/02\/2133.htm","title":{"rendered":"\u6211\u5728\u7814\u7a76\u5982\u4f55\u5bf9\u56fe\u50cf\u8fdb\u884c\u4e8c\u7ef4\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\uff0c\u6c42\u6307\u70b9"},"content":{"rendered":"

\u6211\u53d1\u73b0\u4e86\u4e00\u4e2a\u7ed9\u56fe\u7247\u52a0\u4e0d\u53ef\u89c1\u7684\u6c34\u5370\u7684\u65b9\u6cd5\uff0c \u636e\u8bf4\u8fd9\u79cd\u201c\u76f2\u6c34\u5370\u201d\u4e0d\u5f71\u54cd\u7528\u6237\u4f53\u9a8c\uff0c\u53c8\u80fd\u8ffd\u6eaf\u56fe\u7247\u6765\u6e90\u548c\u4f20\u64ad\u8fc7\u7a0b\uff0c\u5728\u634d\u536b\u7248\u6743\u548c\u77e5\u8bc6\u4ed8\u8d39\u8d8a\u6765\u8d8a\u770b\u91cd\u7684\u73b0\u5728\uff0c\u8fd9\u4e2a\u4e1c\u897f\u5e94\u8be5\u86ee\u6709\u524d\u9014\u7684\u3002\u6211\u5c31\u5728\u60f3\uff0c\u6211\u6ca1\u6709Matlab2010a\u8fd9\u8f6f\u4ef6\uff0c\u6211\u65e0\u6cd5\u4f53\u9a8c\u7ed9\u56fe\u7247\u52a0\u5bc6\uff0c\u6211\u8bd5\u8bd5\u627e\u627e\u80fd\u5426\u7528PHP\u5b9e\u73b0\u5728\u7ebf\u52a0\u76f2\u6c34\u5370\u7684\u529e\u6cd5\uff0c\u5e0c\u671b\u80fd\u505a\u6210WEB\u5e94\u7528\u3002<\/p>\n

\u6211\u5f97\u5230\u7684\u7ebf\u7d22\u6765\u81ea\u8fd9\u91cc\uff1a
\u89e3\u5bc6\uff1a\u963f\u91cc\u5df4\u5df4\u516c\u53f8\u6839\u636e\u622a\u56fe\u67e5\u5230\u6cc4\u9732\u4fe1\u606f\u7684\u5458\u5de5\u7684\u6280\u672f\u662f\u4ec0\u4e48
https:\/\/www.zhihu.com\/question\/50735753<\/a>
\u89e3\u5bc6\uff1a\u963f\u91cc\u5df4\u5df4\u516c\u53f8\u6839\u636e\u622a\u56fe\u67e5\u5230\u6cc4\u9732\u4fe1\u606f\u7684\u5458\u5de5\u7684\u6280\u672f\u662f\u4ec0\u4e48
http:\/\/www.phpchina.com\/portal.php?mod=view&aid=40242<\/a><\/p>\n

\u5927\u6982\u6280\u672f\u7ec6\u8282\u662f\u8fd9\u4e24\u5f20\u56fe\u6765\u89e3\u91ca\uff1a
\u52a0\u6c34\u5370\uff1a<\/p>\n

<\/a><\/div>\n

 \u7136\u540e\u89e3\u6c34\u5370\uff1a<\/p>\n

<\/a><\/div>\n

\u91cc\u9762\u5173\u952e\u7684\u90e8\u5206\u662f\u5bf9\u56fe\u7247\u8fdb\u884c\u201c\u4e8c\u7ef4\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362<\/a>\u201d\uff0c\u82f1\u6587\u53eb Two-Dimensional Fast Fourier Transform\uff0c\u5728\u6280\u672f\u6587\u6863\u91cc\u901a\u5e38\u7b80\u79f0\u4e3aFFT\u3002
<\/a><\/p>\n

\u6211\u9605\u8bfb\u4e86Fuqiang Liu \u7684Matlab2010a\u4e0b\u7684\u6e90\u4ee3\u7801\uff0c\u4e5f\u53bb\u8bfb\u4e86\u300a\u5982\u679c\u770b\u4e86\u6b64\u6587\u4f60\u8fd8\u4e0d\u61c2\u5085\u91cc\u53f6\u53d8\u6362\uff0c\u90a3\u5c31\u8fc7\u6765\u6390\u6b7b\u6211\u5427\u3010\u5b8c\u6574\u7248\u3011 <\/a> <\/span>\u300b\uff0c\u521d\u6b65\u4e86\u89e3\u4e86\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\u662f\u600e\u4e48\u56de\u4e8b\u3002<\/p>\n

\u6211\u627e\u5230\u4ee5\u4e0b\u5173\u4e8eFFT\u7684PHP\u4ee3\u7801\u5b9e\u73b0\u76f8\u5173\u94fe\u63a5\uff1a
https:\/\/www.phpclasses.org\/package\/6193-PHP-Compute-the-Fast-Fourier-Transform-of-sampled-data.html<\/a> \uff0c\u8fd9\u4e2a\u7c7b\u5e93\u80fdCompute the Fast Fourier Transform of sampled data\uff0c\u4f46\u6211\u4e0d\u77e5\u9053\u600e\u4e48\u4f7f\u7528\uff0c\u6709\u6837\u672c\u4ee3\u7801\u6559\u6211\u600e\u4e48\u505aFFT\u548cinverse FFT\u3002
http:\/\/www.jasonbailey.net\/stuff\/php-fast-fourier-transform-fft-brighton-php-october-2013\/<\/a><\/p>\n

\u6211\u4e5f\u5c1d\u8bd5\u627ePHP\u662f\u5426\u652f\u6301 \u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\uff0c\u627e\u5230\u6709\u56fe\u50cf\u7ec4\u4ef6
http:\/\/php.net\/manual\/zh\/book.imagick.php<\/a> \u4e0b\u7684 Imagick::forwardFourierTransformImage<\/a> \u662f\u652f\u6301 \u201c\u79bb\u6563\u5085\u91cc\u53f6\u53d8\u6362\u201d\uff0c\u82f1\u6587\u662fdiscrete Fourier transform (DFT) \uff0c\u4f46\u4e0d\u77e5\u9053\u4e0e\u201c\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\u201dFast Fourier Transform\uff08FFT\uff09\u6709\u4ec0\u4e48\u5dee\u522b\u3002<\/p>\n

\u8fd9\u91cc\u8fd8\u6709\u4e00\u4e2a Two-Dimensional Fast Fourier Transform\uff08\u4e8c\u7ef4\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\uff09 \u7684\u6587\u7ae0\uff0c
http:\/\/imagejdocu.tudor.lu\/doku.php?id=gui:process:fft<\/a> \u4e5f\u662f\u57fa\u4e8e Matlab\u5728\u8bb2\u3002<\/p>\n

\u73b0\u5728\u95ee\u9898\u662f\uff0c\u7528php\u91cc\u7684imagecopy\u51fd\u6570\u5408\u5e76\u80cc\u666f\u56fe\u7247\u548c\u6c34\u5370\u5230\u540c\u4e00\u5f20\u7167\u7247\u7684\u529f\u80fd\u6211\u6d4b\u8bd5\u901a\u8fc7\u4e86\uff0c\u5982\u4f55\u7528FFT\u7684\u7c7b\u5e93\u5bf9\u56fe\u7247\u4f5cFFT\u548cinverse FFT\u64cd\u4f5c\uff1f\u6c42\u6709\u56fe\u50cf\u5904\u7406\u7ecf\u9a8c\u7684\u7684\u9ad8\u624b\u6307\u5bfc\u4e00\u4e0b\uff0c\u6211\u5df2\u7ecf\u8bd5\u8fc7\u7528\u82f1\u6587\u641c\u7d22\u4e86\uff0c\u5982 php Fourier image \/ php fft convert image \/ ,\u627e\u5230\u8fd9\u4e9b\u94fe\u63a5\uff0chttp:\/\/www.fmwconcepts.com\/misc_tests\/FFT_tests\/<\/a>
http:\/\/www.roborealm.com\/help\/FFT.php<\/a>
\u90fd\u4e0d\u77e5\u9053\u5982\u4f55\u4f7f\u7528\u5085\u91cc\u53f6\u53d8\u6362\u5bf9\u56fe\u7247\u8fdb\u884c\u64cd\u4f5c\u3002<\/p>\n

\u76f2\u6c34\u5370\u6709\u4eba\u7528clojure\u5199\u4e86\u4e00\u4e2a\uff0c\u8fd8\u516c\u5f00\u4e86\u6e90\u4ee3\u7801\uff1a\u4e00\u4e2a\u667a\u6167\u7684\u6c34\u5370 – Share – Clojure China http:\/\/clojure-china.org\/t\/topic\/545<\/a><\/span><\/p>\n

\u6e90\u4ee3\u78bc\u5728\u9019\uff1a <\/span><\/span>https:\/\/github.com\/lostpupil\/hidden-watermark<\/a><\/div>\n

\u4e0b\u9762\u662fFuqiang Liu \u7684Matlab2010a\u4e0b\u7684\u6e90\u4ee3\u7801\uff1a<\/p>\n

\n
%%\u5085\u91cc\u53f6\u53d8\u6362\u52a0\u6c34\u5370\u6e90\u4ee3\u7801<\/span>
%% \u8fd0\u884c\u73af\u5883Matlab2010a <\/span>
clc<\/span>;<\/span>clear<\/span>;<\/span>close<\/span> all<\/span>;<\/span>
alpha<\/span> =<\/span> 1<\/span>;<\/span>

%% read data<\/span>
im<\/span> =<\/span> double<\/span>(<\/span>imread<\/span>(<\/span>'gl1.jpg'<\/span>))<\/span>\/<\/span>255<\/span>;<\/span>
mark<\/span> =<\/span> double<\/span>(<\/span>imread<\/span>(<\/span>'watermark.jpg'<\/span>))<\/span>\/<\/span>255<\/span>;<\/span>
figure<\/span>,<\/span> imshow<\/span>(<\/span>im<\/span>),<\/span>title<\/span>(<\/span>'original image'<\/span>);<\/span>
figure<\/span>,<\/span> imshow<\/span>(<\/span>mark<\/span>),<\/span>title<\/span>(<\/span>'watermark'<\/span>);<\/span>

%% encode mark<\/span>
imsize<\/span> =<\/span> size<\/span>(<\/span>im<\/span>);<\/span>
%random<\/span>
TH<\/span>=<\/span>zeros<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>,<\/span>imsize<\/span>(<\/span>2<\/span>),<\/span>imsize<\/span>(<\/span>3<\/span>));<\/span>
TH1<\/span> =<\/span> TH<\/span>;<\/span>
TH1<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>mark<\/span>,<\/span>1<\/span>),<\/span>1<\/span>:<\/span>size<\/span>(<\/span>mark<\/span>,<\/span>2<\/span>),:)<\/span> =<\/span> mark<\/span>;<\/span>
M<\/span>=<\/span>randperm<\/span>(<\/span>0.5<\/span>*<\/span>imsize<\/span>(<\/span>1<\/span>));<\/span>
N<\/span>=<\/span>randperm<\/span>(<\/span>imsize<\/span>(<\/span>2<\/span>));<\/span>
save<\/span>(<\/span>'encode.mat'<\/span>,<\/span>'M'<\/span>,<\/span>'N'<\/span>);<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        TH<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:)=<\/span>TH1<\/span>(<\/span>M<\/span>(<\/span>i<\/span>),<\/span>N<\/span>(<\/span>j<\/span>),:);<\/span>
    end<\/span>
end<\/span>
% symmetric<\/span>
mark_<\/span> =<\/span> zeros<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>),<\/span>imsize<\/span>(<\/span>2<\/span>),<\/span>imsize<\/span>(<\/span>3<\/span>));<\/span>
mark_<\/span>(<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>,<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>),:)=<\/span>TH<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        mark_<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>+<\/span>1<\/span>-<\/span>i<\/span>,<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>+<\/span>1<\/span>-<\/span>j<\/span>,:)=<\/span>TH<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>mark_<\/span>),<\/span>title<\/span>(<\/span>'encoded watermark'<\/span>);<\/span>
%imwrite(mark_,'encoded watermark.jpg');<\/span>

%% add watermark<\/span>
FA<\/span>=<\/span>fft2<\/span>(<\/span>im<\/span>);<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>FA<\/span>);<\/span>title<\/span>(<\/span>'spectrum of original image'<\/span>);<\/span>
FB<\/span>=<\/span>FA<\/span>+<\/span>alpha<\/span>*<\/span>double<\/span>(<\/span>mark_<\/span>);<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>FB<\/span>);<\/span> title<\/span>(<\/span>'spectrum of watermarked image'<\/span>);<\/span>
FAO<\/span>=<\/span>ifft2<\/span>(<\/span>FB<\/span>);<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>FAO<\/span>);<\/span> title<\/span>(<\/span>'watermarked image'<\/span>);<\/span>
%imwrite(uint8(FAO),'watermarked image.jpg');<\/span>
RI<\/span> =<\/span> FAO<\/span>-<\/span>double<\/span>(<\/span>im<\/span>);<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>uint8<\/span>(<\/span>RI<\/span>));<\/span> title<\/span>(<\/span>'residual'<\/span>);<\/span>
%imwrite(uint8(RI),'residual.jpg');<\/span>
xl<\/span> =<\/span> 1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>);<\/span>
yl<\/span> =<\/span> 1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>);<\/span>
[<\/span>xx<\/span>,<\/span>yy<\/span>]<\/span> =<\/span> meshgrid<\/span>(<\/span>xl<\/span>,<\/span>yl<\/span>);<\/span>
figure<\/span>,<\/span> plot3<\/span>(<\/span>xx<\/span>,<\/span>yy<\/span>,<\/span>FA<\/span>(:,:,<\/span>1<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FA<\/span>(:,:,<\/span>2<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FA<\/span>(:,:,<\/span>3<\/span>)<\/span>.^<\/span>2<\/span>),<\/span>title<\/span>(<\/span>'spectrum of original image'<\/span>);<\/span>
figure<\/span>,<\/span> plot3<\/span>(<\/span>xx<\/span>,<\/span>yy<\/span>,<\/span>FB<\/span>(:,:,<\/span>1<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FB<\/span>(:,:,<\/span>2<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FB<\/span>(:,:,<\/span>3<\/span>)<\/span>.^<\/span>2<\/span>),<\/span>title<\/span>(<\/span>'spectrum of watermarked image'<\/span>);<\/span>
figure<\/span>,<\/span> plot3<\/span>(<\/span>xx<\/span>,<\/span>yy<\/span>,<\/span>FB<\/span>(:,:,<\/span>1<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FB<\/span>(:,:,<\/span>2<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FB<\/span>(:,:,<\/span>3<\/span>)<\/span>.^<\/span>2<\/span>-<\/span>FA<\/span>(:,:,<\/span>1<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FA<\/span>(:,:,<\/span>2<\/span>)<\/span>.^<\/span>2<\/span>+<\/span>FA<\/span>(:,:,<\/span>3<\/span>)<\/span>.^<\/span>2<\/span>),<\/span>title<\/span>(<\/span>'spectrum of watermark'<\/span>);<\/span>

%% extract watermark<\/span>
FA2<\/span>=<\/span>fft2<\/span>(<\/span>FAO<\/span>);<\/span>
G<\/span>=(<\/span>FA2<\/span>-<\/span>FA<\/span>)<\/span>\/<\/span>alpha<\/span>;<\/span>
GG<\/span>=<\/span>G<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>M<\/span>(<\/span>i<\/span>),<\/span>N<\/span>(<\/span>j<\/span>),:)=<\/span>G<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>+<\/span>1<\/span>-<\/span>i<\/span>,<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>+<\/span>1<\/span>-<\/span>j<\/span>,:)=<\/span>GG<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>GG<\/span>);<\/span>title<\/span>(<\/span>'extracted watermark'<\/span>);<\/span>
%imwrite(uint8(GG),'extracted watermark.jpg');<\/span>

%% MSE and PSNR<\/span>
C<\/span>=<\/span>double<\/span>(<\/span>im<\/span>);<\/span>
RC<\/span>=<\/span>double<\/span>(<\/span>FAO<\/span>);<\/span>
MSE<\/span>=<\/span>0<\/span>;<\/span> PSNR<\/span>=<\/span>0<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        MSE<\/span>=<\/span>MSE<\/span>+<\/span>(<\/span>C<\/span>(<\/span>i<\/span>,<\/span>j<\/span>)<\/span>-<\/span>RC<\/span>(<\/span>i<\/span>,<\/span>j<\/span>))<\/span>.^<\/span>2<\/span>;<\/span>
    end<\/span>
end<\/span>
MSE<\/span>=<\/span>MSE<\/span>\/<\/span>360.<\/span>^2<\/span>;<\/span>
PSNR<\/span>=<\/span>20<\/span>*<\/span>log10<\/span>(<\/span>255<\/span>\/<\/span>sqrt<\/span>(<\/span>MSE<\/span>));<\/span>
MSE<\/span>
PSNR<\/span>

%% attack test<\/span>
%% attack by smearing<\/span>
%A = double(imread('gl1.jpg'));<\/span>
%B = double(imread('attacked image.jpg'));<\/span>
attack<\/span> =<\/span> 1<\/span>-<\/span>double<\/span>(<\/span>imread<\/span>(<\/span>'attack.jpg'<\/span>))<\/span>\/<\/span>255<\/span>;<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>attack<\/span>);<\/span>
FAO_<\/span> =<\/span> FAO<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        if<\/span> attack<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>1<\/span>)<\/span>+<\/span>attack<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>2<\/span>)<\/span>+<\/span>attack<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>3<\/span>)<\/span>><\/span>0.5<\/span>
            FAO_<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:)<\/span> =<\/span> attack<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
        end<\/span>
    end<\/span>
end<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>FAO_<\/span>);<\/span>
%extract watermark<\/span>
FA2<\/span>=<\/span>fft2<\/span>(<\/span>FAO_<\/span>);<\/span>
G<\/span>=(<\/span>FA2<\/span>-<\/span>FA<\/span>)<\/span>*<\/span>2<\/span>;<\/span>
GG<\/span>=<\/span>G<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>M<\/span>(<\/span>i<\/span>),<\/span>N<\/span>(<\/span>j<\/span>),:)=<\/span>G<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>+<\/span>1<\/span>-<\/span>i<\/span>,<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>+<\/span>1<\/span>-<\/span>j<\/span>,:)=<\/span>GG<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>GG<\/span>);<\/span>title<\/span>(<\/span>'extracted watermark'<\/span>);<\/span>

%% attack by cutting<\/span>
s2<\/span> =<\/span> 0.8<\/span>;<\/span>
FAO_<\/span> =<\/span> FAO<\/span>;<\/span>
FAO_<\/span>(:,<\/span>s2<\/span>*<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>+<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>),:)<\/span> =<\/span> FAO_<\/span>(:,<\/span>1<\/span>:<\/span>int32<\/span>((<\/span>1<\/span>-<\/span>s2<\/span>)<\/span>*<\/span>imsize<\/span>(<\/span>2<\/span>)),:);<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>FAO_<\/span>);<\/span>
%extract watermark<\/span>
FA2<\/span>=<\/span>fft2<\/span>(<\/span>FAO_<\/span>);<\/span>
G<\/span>=(<\/span>FA2<\/span>-<\/span>FA<\/span>)<\/span>*<\/span>2<\/span>;<\/span>
GG<\/span>=<\/span>G<\/span>;<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>M<\/span>(<\/span>i<\/span>),<\/span>N<\/span>(<\/span>j<\/span>),:)=<\/span>G<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>*<\/span>0.5<\/span>
    for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>
        GG<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>)<\/span>+<\/span>1<\/span>-<\/span>i<\/span>,<\/span>imsize<\/span>(<\/span>2<\/span>)<\/span>+<\/span>1<\/span>-<\/span>j<\/span>,:)=<\/span>GG<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,:);<\/span>
    end<\/span>
end<\/span>
figure<\/span>,<\/span>imshow<\/span>(<\/span>GG<\/span>);<\/span>title<\/span>(<\/span>'extracted watermark'<\/span>);<\/span>


%%\u5c0f\u6ce2\u53d8\u6362\u52a0\u6c34\u5370\uff0c\u89e3\u6c34\u5370\u5927\u5bb6\u6309\u7167\u52a0\u7684\u601d\u8def\u9006\u8fc7\u6765\u5c31\u597d<\/span>
clc<\/span>;<\/span>clear<\/span>;<\/span>close<\/span> all<\/span>;<\/span>
%% read data<\/span>
im<\/span> =<\/span> double<\/span>(<\/span>imread<\/span>(<\/span>'gl1.jpg'<\/span>))<\/span>\/<\/span>255<\/span>;<\/span>
mark<\/span> =<\/span> double<\/span>(<\/span>imread<\/span>(<\/span>'watermark.jpg'<\/span>))<\/span>\/<\/span>255<\/span>;<\/span>
figure<\/span>,<\/span> imshow<\/span>(<\/span>im<\/span>),<\/span>title<\/span>(<\/span>'original image'<\/span>);<\/span>
figure<\/span>,<\/span> imshow<\/span>(<\/span>mark<\/span>),<\/span>title<\/span>(<\/span>'watermark'<\/span>);<\/span>
%% RGB division<\/span>
im<\/span>=<\/span>double<\/span>(<\/span>im<\/span>);<\/span> 
mark<\/span>=<\/span>double<\/span>(<\/span>mark<\/span>);<\/span> 
imr<\/span>=<\/span>im<\/span>(:,:,<\/span>1<\/span>);<\/span> 
markr<\/span>=<\/span>mark<\/span>(:,:,<\/span>1<\/span>);<\/span> 
img<\/span>=<\/span>im<\/span>(:,:,<\/span>2<\/span>);<\/span> 
markg<\/span>=<\/span>mark<\/span>(:,:,<\/span>2<\/span>);<\/span> 
imb<\/span>=<\/span>im<\/span>(:,:,<\/span>3<\/span>);<\/span> 
markb<\/span>=<\/span>mark<\/span>(:,:,<\/span>3<\/span>);<\/span> 
%% parameter<\/span>
r<\/span>=<\/span>0.04<\/span>;<\/span> 
g<\/span> =<\/span> 0.04<\/span>;<\/span> 
b<\/span> =<\/span> 0.04<\/span>;<\/span>
%% wavelet tranform and add watermark<\/span>
% for red<\/span>
[<\/span>Cwr<\/span>,<\/span>Swr<\/span>]=<\/span>wavedec2<\/span>(<\/span>markr<\/span>,<\/span>1<\/span>,<\/span>'haar'<\/span>);<\/span> 
[<\/span>Cr<\/span>,<\/span>Sr<\/span>]=<\/span>wavedec2<\/span>(<\/span>imr<\/span>,<\/span>2<\/span>,<\/span>'haar'<\/span>);<\/span> 
% add watermark<\/span>
Cr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>)=<\/span>... <\/span>
Cr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>)<\/span>+<\/span>r<\/span>*<\/span>Cwr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>);<\/span> 
k<\/span>=<\/span>0<\/span>;<\/span> 
while<\/span> k<\/span><<\/span>=<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>-<\/span>1<\/span> 
Cr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
r<\/span>*<\/span>Cwr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>);<\/span> 
Cr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
r<\/span>*<\/span>Cwr<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 
Cr<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cr<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
r<\/span>*<\/span>Cwr<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>));<\/span> 
k<\/span>=<\/span>k<\/span>+<\/span>1<\/span>;<\/span> 
end<\/span>;<\/span> 
Cr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>r<\/span>*<\/span>Cwr<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwr<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 

% for green<\/span>
[<\/span>Cwg<\/span>,<\/span>Swg<\/span>]=<\/span>WAVEDEC2<\/span>(<\/span>markg<\/span>,<\/span>1<\/span>,<\/span>'haar'<\/span>);<\/span> 
[<\/span>Cg<\/span>,<\/span>Sg<\/span>]=<\/span>WAVEDEC2<\/span>(<\/span>img<\/span>,<\/span>2<\/span>,<\/span>'haar'<\/span>);<\/span> 
Cg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>)=<\/span>... <\/span>
Cg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>)<\/span>+<\/span>g<\/span>*<\/span>Cwg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>);<\/span> 
k<\/span>=<\/span>0<\/span>;<\/span> 
while<\/span> k<\/span><<\/span>=<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>-<\/span>1<\/span> 
Cg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
g<\/span>*<\/span>Cwg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>);<\/span> 
Cg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
g<\/span>*<\/span>Cwg<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 
Cg<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cg<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
g<\/span>*<\/span>Cwg<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>));<\/span> 
k<\/span>=<\/span>k<\/span>+<\/span>1<\/span>;<\/span> 
end<\/span>;<\/span> 
Cg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>g<\/span>*<\/span>Cwg<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwg<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 

% for blue<\/span>
[<\/span>Cwb<\/span>,<\/span>Swb<\/span>]=<\/span>WAVEDEC2<\/span>(<\/span>markb<\/span>,<\/span>1<\/span>,<\/span>'haar'<\/span>);<\/span> 
[<\/span>Cb<\/span>,<\/span>Sb<\/span>]=<\/span>WAVEDEC2<\/span>(<\/span>imb<\/span>,<\/span>2<\/span>,<\/span>'haar'<\/span>);<\/span> 
Cb<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>)<\/span>+<\/span>b<\/span>*<\/span>Cwb<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>16<\/span>);<\/span> 
k<\/span>=<\/span>0<\/span>;<\/span> 
while<\/span> k<\/span><<\/span>=<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>-<\/span>1<\/span> 
Cb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
g<\/span>*<\/span>Cwb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>);<\/span> 
Cb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
b<\/span>*<\/span>Cwb<\/span>(<\/span>1<\/span>+<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>2<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 
Cb<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cb<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>... <\/span>
k<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>+<\/span>(<\/span>k<\/span>+<\/span>1<\/span>)<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>... <\/span>
b<\/span>*<\/span>Cwb<\/span>(<\/span>1<\/span>+<\/span>3<\/span>*<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>));<\/span> 
k<\/span>=<\/span>k<\/span>+<\/span>1<\/span>;<\/span> 
end<\/span>;<\/span> 
Cb<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)=<\/span>Cb<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>)<\/span>+<\/span>b<\/span>*<\/span>Cwb<\/span>(<\/span>1<\/span>:<\/span>size<\/span>(<\/span>Cwb<\/span>,<\/span>2<\/span>)<\/span>\/<\/span>4<\/span>);<\/span> 
%% image reconstruction<\/span>
imr<\/span>=<\/span>WAVEREC2<\/span>(<\/span>Cr<\/span>,<\/span>Sr<\/span>,<\/span>'haar'<\/span>);<\/span> 
img<\/span>=<\/span>WAVEREC2<\/span>(<\/span>Cg<\/span>,<\/span>Sg<\/span>,<\/span>'haar'<\/span>);<\/span> 
imb<\/span>=<\/span>WAVEREC2<\/span>(<\/span>Cb<\/span>,<\/span>Sb<\/span>,<\/span>'haar'<\/span>);<\/span> 
imsize<\/span>=<\/span>size<\/span>(<\/span>imr<\/span>);<\/span> 
FAO<\/span>=<\/span>zeros<\/span>(<\/span>imsize<\/span>(<\/span>1<\/span>),<\/span>imsize<\/span>(<\/span>2<\/span>),<\/span>3<\/span>);<\/span> 
for<\/span> i<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>1<\/span>);<\/span> 
for<\/span> j<\/span>=<\/span>1<\/span>:<\/span>imsize<\/span>(<\/span>2<\/span>);<\/span> 
FAO<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>1<\/span>)=<\/span>imr<\/span>(<\/span>i<\/span>,<\/span>j<\/span>);<\/span> 
FAO<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>2<\/span>)=<\/span>img<\/span>(<\/span>i<\/span>,<\/span>j<\/span>);<\/span> 
FAO<\/span>(<\/span>i<\/span>,<\/span>j<\/span>,<\/span>3<\/span>)=<\/span>imb<\/span>(<\/span>i<\/span>,<\/span>j<\/span>);<\/span> 
end<\/span> 
end<\/span> 
figure<\/span>,<\/span> imshow<\/span>(<\/span>FAO<\/span>);<\/span> title<\/span>(<\/span>'watermarked image'<\/span>);<\/span><\/code><\/pre>\n<\/blockquote>\n
<\/p>\n
\u6765\u81ea\u5468\u66d9\u5149\u7684BLOGSPOT\u7a7a\u95f4<\/div>\n","protected":false},"excerpt":{"rendered":"
\u6211\u53d1\u73b0\u4e86\u4e00\u4e2a\u7ed9\u56fe\u7247\u52a0\u4e0d\u53ef\u89c1\u7684\u6c34\u5370\u7684\u65b9\u6cd5\uff0c \u636e\u8bf4\u8fd9\u79cd\u201c\u76f2\u6c34\u5370\u201d\u4e0d\u5f71\u54cd\u7528\u6237\u4f53\u9a8c\uff0c\u53c8\u80fd Continue Reading …<\/a><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2133","post","type-post","status-publish","format-standard","hentry","category-random"],"views":306,"_links":{"self":[{"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/posts\/2133","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/comments?post=2133"}],"version-history":[{"count":0,"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/posts\/2133\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/media?parent=2133"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/categories?post=2133"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zuola.com\/weblog\/wp-json\/wp\/v2\/tags?post=2133"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}