%直方圖均衡化??
clear?all
close?all
clc
DIR=‘D:\直方圖均衡\data\Imgs_MSRA\‘;
str=dirr（DIR）;
for?k=1:length（str）
?close?all
I_in?=?imread（strcat（DIRstr（k）.name））;?
I_in?=?imresize（I_in[300400]）;
%%%%%%%%%%%%%%%%計算標準差%%%%%%%%%%%%%%%%%%%%%%%%%
%?std_m=std_function（I_in）;
%%%%%%%%%%%%%%%%%%end%%%%%%%%%%%%%%%%%%%%%%%
%?if?std_m<0.0249
I=rgb2gray（I_in）;
I_gray?=?I;
%for?cn=1:size（I_in3）
I_matlab=histeq（I）;?
I_o=I;
[heightwidth]?=?size（I）;???
S_I_gray?=?0;
S_I_e?=?0;
%進行像素灰度統(tǒng)計;??
NumPixel?=?zeros（1256）;%統(tǒng)計各灰度數(shù)目，共256個灰度級??
for?i?=?1:height??
????for?j?=?1:?width??
????????NumPixel（I（ij）?+?1）?=?NumPixel（I（ij）?+?1）?+?1;%對應(yīng)灰度值像素點數(shù)量增加一??
????end??
end??
%計算灰度分布密度??
for?i?=?1:256??
????ProbPixel（i）?=?NumPixel（i）?/?（height?*?width?*?0.8）;??
end?
%計算累計直方圖分布??
CumuPixel?=?zeros（1256）;??
for?i?=?1:256??
????if?i?==?1??
????????CumuPixel（i）?=?ProbPixel（i）;??
????else??
%?j=（sum（ProbPixel（1:i）））/（height?*?width?*?1.0-（sum（ProbPixel（1:i））））;
?j=（sum（ProbPixel（1:i）））/（1+sum（ProbPixel（1:i）））;
%?j=（sum（ProbPixel（1:i-1）））*（1-ProbPixel（i）+0.5）;
CumuPixel（i）=j;?
????end??
end??
CumuPixel=CumuPixel/（max（CumuPixel）-min（CumuPixel））;
%累計分布取整??
CumuPixel?=?uint8（255?.*?CumuPixel?+?0.8）;??
%對灰度值進行映射（均衡化）??
I2=im2double（I）;
Im=filter2（fspecial（‘a(chǎn)verage‘5）I）/255;?
for?i?=?1:height??
????for?j?=?1:?width
????????if?I（ij）==0
?????????I（ij）=1;
????????end
?????????I_e（ij）?=?CumuPixel（I（ij））+（I2（ij）-Im（ij））*255;
%???????????I_e（ij）?=?CumuPixel（I（ij））;
????????%方案一
%?????????if?I_e（ij）>=230
%??????????