我正在尝试实现一个简单的函数，它与 MatLab 的默认 hist() 相同。
我们有两张不同亮度的相同图像，我们必须将它们转换为灰度，然后使用 MatLab 的默认功能hist() 来获取直方图（到目前为止一切都很好！）。
然后我们必须实现函数 hist my_hist()，当我试图计算强度的频率时，结果是不一样的。
似乎它总结了 254 和 255 到 254 和 255 的频率为零！我不知道问题是什么，任何帮助将不胜感激。
这是命令行的代码：
%Read the images and convert them from rgb to grayscale
i=imread('pic1.jpg');
j=rgb2gray(i);
x=imread('pic2.jpg');
y=rgb2gray(x);
%Display the two images
figure
imshow(j)
figure
imshow(y)
%Display the histogram of the two images
[a,b] = hist(j(:),0:1:255);
figure
plot(b,a)
[c,d]=hist(y(:),0:1:255);
figure
plot(d,c)
%Call of the built-in function
my_hist('pic1.jpg','pic2.jpg')
这是自建函数的代码：
function []= my_hist( x,y)
%Read the images and convert them from rgb to grayscale
pic1=imread(x);
i=rgb2gray(pic1);
pic2=imread(y);
j=rgb2gray(pic2);
%Initialize two vectors to be the axis for histogram
plotx=0:255;
ploty=zeros(1,256);
%Take the dimensions of the first image pic1
[m,n] = size(i);
%With 2 loops we go through the matrix of the image and count how many
%pixels have the same intensity
for k=1:m
for l=1:n
num=i(k,l)+1;
ploty(num)=ploty(num)+1;
end
end
%Display the histogram for the first image pic1
figure
plot(plotx,ploty);
%Initialize two vectors to be the axis for histogram
plotx2=0:255;
ploty2=zeros(1,256);
%Take the dimensions of the second image pic2
[m2,n2] = size(j);
%With 2 loops we go through the matrix of the image and count how many
%pixels have the same intensity
for o=1:m2
for p=1:n2
num2=j(o,p)+1;
ploty2(num2)=ploty2(num2)+1;
end
end
%Display the histogram for the second image pic2
figure
plot(plotx2,ploty2);
end
