matlab 图像直方图均衡化

>> sample = imread('sample.jpg');
>> imshow(sample);
>> [M,N]=size(sample);
>> [counts,x]=imhist(sample,32);
>> counts=counts/M/N;
>> stem(x,counts);

>> histeqSample = histeq(sample);

>> subplot(2,2,1);
>> imshow(sample);  %原始图像
>> subplot(2,2,2);
>> stem(x,counts);  %原始图像直方图
>> subplot(2,2,3);
>> imshow(histeqSample); %均衡化处理后的图像
>> subplot(2,2,4);
>> [M,N]=size(histeqSample);
>> [counts,x]=imhist(histeqSample,32);
>> counts=counts/M/N;
stem(x,counts); %均衡化处理后图像直方图