function?thr?=?Birge_Massart（c?s）
%用Birge-Massart策略估計(jì)閾值
%?給定分解層數(shù)j，對(duì)j+1及更高層，所有系數(shù)保留
%?對(duì)第i層（1<=i<=j），保留絕對(duì)值最大的n_i個(gè)系數(shù)，n_i由下式確定
%???n_i?=?M/（j+2-i）^alpha
%?其中M和alpha為經(jīng)驗(yàn)系數(shù)，缺省情況下M取第一層分解后的系數(shù)長(zhǎng)度L（1）
%?一般情況下，M滿足?L（1）<=M<=2L（1）
%?alpha的取值因用途不同，壓縮情況下一般取alpha=1.5，降噪一般取alpha=3

%設(shè)定alpha、M和j的值
alpha?=?3;
M?=?prod（s（1?:））;
j?=?size（s?1）?-?2;

%計(jì)算每層的閾值
for?i?=?1:j
????n?=?round（?M/（j+2-i）^alpha?）;???????????????????%每層保留的系數(shù)個(gè)數(shù)
????D?=?detcoef2（‘compact‘?c?s?i）;???????????????%提取第i層的所有細(xì)節(jié)系數(shù)?
????if?n?>=?size（D）
????????thr（:?i）?=?zeros（3?1）;
????else
????????D?=?sort（abs（D））;???????????????????????????%排序
????????thr（i）?=?D（end-n）;??????????????????????????%設(shè)置第i層的閾值
????end
end

?屬性????????????大小?????日期????時(shí)間???名稱
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?????文件????????844??2007-07-09?15:05??畢設(shè)\Birge_Massart.m

?????文件????????767??2007-07-09?15:55??畢設(shè)\den1.m

?????文件???????1113??2007-07-09?15:55??畢設(shè)\den1_10.m

?????文件???????1600??2007-07-09?15:54??畢設(shè)\den1_5_1.m

?????文件????????796??2007-07-09?15:55??畢設(shè)\den1_9.m

?????文件????????756??2007-07-09?15:55??畢設(shè)\den2.m

?????文件????????856??2007-06-07?08:28??畢設(shè)\den3.m

?????文件???????2808??2007-07-09?15:57??畢設(shè)\den4.m

?????文件???????4356??2007-07-09?15:58??畢設(shè)\denoise0615.m

?????文件???????5379??2007-07-09?15:22??畢設(shè)\denoise0701.m

?????文件????????492??2007-06-28?19:33??畢設(shè)\Donoho.m

?????文件?????150923??2000-10-07?15:18??畢設(shè)\lena.png

?????文件?????476195??2000-10-07?15:05??畢設(shè)\lena_color.png

?????文件????????492??2007-07-09?15:18??畢設(shè)\meanfilter.m

?????文件????????581??2007-07-09?15:18??畢設(shè)\medfilter.m

?????文件????????189??2007-07-02?09:22??畢設(shè)\MSE.m

?????文件????????281??2007-07-09?15:52??畢設(shè)\MSE_color.m

?????文件???????1051??2007-07-01?09:57??畢設(shè)\noise.m

?????文件????????101??2007-05-23?15:27??畢設(shè)\PSNR.m

?????文件????????113??2007-07-02?09:29??畢設(shè)\PSNR_color.m

?????文件???????1754??2007-06-28?21:27??畢設(shè)\wdenoise.m

?????文件???????1778??2007-07-09?16:03??畢設(shè)\文件清單及說(shuō)明.txt

?????目錄??????????0??2009-09-15?16:45??畢設(shè)

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???????????????653225????????????????????23