[求助]关于matlab Otsu阈值分割中的阈值问题！！！

[johnny8088]

作者: daocaoren_508

用Otsu方法进行图像阈值分割：
I = imread('coins.png');
level = graythresh(I);
BW = im2bw(I,level);

可是求得的level为什么是0到1之间的数呢？
怎样求实际的阈值？

假如一个灰度图像每个像素点的灰度值是0到...

I cannot believe nobody answers this question.
I believe anybody seriously working on image processing uses Otsu's method a lot.
Yes, the threshold is between 0-1.
If you want the actual number, simply use this

actual_level=255*level;

Why the level is between 0-1? it is normalized because some image gray levels are not between 0-255. The gray levels can be in 0-2^(16)-1. So when normalized, the threshold is same for all types of images.

I wish this answers your question.