中文说明：在图像处理过程中 ，灰度化之后，对阈值的设定很重要的，因此合适的阈值设定能获得更好的二值化效果。本源代码采用迭代算法，可获得很好的阈值，从而使图像处理更加精确。
English Description：
In image processing, after gray, threshold setting is very important, therefore suitable threshold setting can get better binary effect. Source code using iterative algorithm can be obtained very good threshold, allowing more accurate image processing.