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%計算圖像對比度
%中心像素灰度值與周圍8近鄰像素灰度值之差的平方之和，除以以上之差的個數。
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clear;
clc;
format?long;
[filenamepathname]?=?uigetfile（{‘*.jpg;*.bmp;*.png‘}‘打開待測對比度的圖像‘）;
if?filename?==?0
????return;
end
pic?=?imread（[pathnamefilename]）;
[mnl]?=?size（pic）;%求原始圖像的行數m和列數n
if?l>=2
????pic?=?rgb2gray（pic）;?
end
g?=?padarray（pic[1?1]‘symmetric‘‘both‘）;%對原始圖像進行擴展
[rc]?=?size（g）;%求擴展后圖像的行數r和列數c
g?=?double（g）;?%把擴展后圖像轉變成雙精度浮點數
k?=?0.0;?%定義一數值k，初始值為0
for?i=2:r-1
????for?j=2:c-1
????????k?=?k+（g（ij-1）-g（ij））^2+（g（i-1j）-g（ij））^2+（g（ij+1）-g（ij））^2+（g（i+1j）-g（ij））^2+（g（i-1j-1）-g（ij））^2+（g（i-1j+1）-g（ij））^2+（g（i+1j-1）-g（ij））^2+（g（i+1j+1）-g（ij））^2;
????end
end
%計算原始圖像對比度
c?=?k/（8*（m-2）*（n-2）+6*（2*（m-2）+2*（n-2））+4*3）;
%c?=?k/（8*（m-2）*（n-2）+5*（2*（m-2）+2*（n-2））+4*3）;
c%輸出對比度

?屬性????????????大小?????日期????時間???名稱
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?????文件???????1086??2019-08-20?16:54??duibidujisaun.m

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?????????????????1086????????????????????1