说明：  编写一个自动估计阈值的全局阈值化程序。程序的输出为分割后的二值图。并要求用上面编写的阈值化程序对图中的目标进行分割。
(The preparation of an automatic threshold estimate the overall procedure threshold. Procedures after the partition of the output of the binary image. And requested the use of above the threshold of the preparation process of the target map partition.)