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我正在尝试自己编写直方图均衡化代码,但结果与 matlab 中的内置函数不同histeq。任何建议为什么会发生这种情况?我附上了代码和结果。输出图像 输出直方图

%% Histogram Equalization
close all
clear all
%%
I = imread('Iris_virginica.jpg');
grayI = rgb2gray(I);
[m,n] = size(grayI);
L = 256;
[counts,x] = imhist(grayI);
myCDF = cumsum(counts)/(m*n);
equalizedI = (L-1)*myCDF(double(grayI)+1);
equalizedI = uint8(equalizedI);
histMyOut = imhist(equalizedI);
builtInEqualizationI = histeq(grayI);
histBuiltInEqu = imhist(builtInEqualizationI);
%%
figure
subplot(1,3,1), stem(x,counts), title('Histogram');
subplot(1,3,2), stem(x,myCDF), title('Commulative Distribution');
subplot(1,3,3), stem(x,imhist(equalizedI)), title('Equalized');

figure
subplot(1,3,1),imshow(grayI), title('Input image');
subplot(1,3,2), imshow(equalizedI), title('Equalized image (mine)');
subplot(1,3,3), imshow(builtInEqualizationI), title('Equalized image (matlab)');

figure
subplot(1,3,1), stem(x,counts), title('Histogram');
subplot(1,3,2), stem(x,histMyOut), title('Equalized Histogram (mine)');
subplot(1,3,3), stem(x,histBuiltInEqu), title('Equalized Histogram (matlab)');

difference = abs(equalizedI-builtInEqualizationI);
figure, imshow(difference,[]);
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1 回答 1

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histeq默认情况下使用 64 个 bin 来均衡您的直方图。您正在使用histeq. 尝试做:

builtInEqualizationI = histeq(grayI, 256);

...指定 256 个箱进行均衡,因为您的手动代码正在使用那么多箱进行均衡。第二个参数覆盖默认值并通知histeq使用那么多箱来执行均衡。

于 2016-07-23T22:20:45.177 回答