Thresholding is a very basic operation in image processing
Edit by : Thresholding is a very basic operation in image processing. And, a good Algorithm always begins with a good basis! Otsu thresholding is a simple yet effective global automatic thresholding method for binarizing grayscale images such as foregrounds and backgrounds.

In image processing, Otsu鈥檚 thresholding method (1979) is used for automatic binarization level decision, based on the shape of the histogram. The algorithm assumes that the image is composed of two basic classes: Foreground and Background. It then computes an optimal Threshold value that minimizes the weighted within class variances of these two classes. It is mathematically proven that minimizing the within class variance is same as maximizing the Between class variance.

Otsu threshold is used in many applications from medical imaging to low level computer vision. It has many advantages and assumptions.

Features:

* Speed: Because Otsu threshold operates on histograms (which are integer or float arrays of length 256), it鈥檚 quite fast.
* Ease of coding: Approximately 80 lines of very easy stuff. you can free download Otsu Threshold now.