otsu （大津算法）又名最大类间差方法，通过统计整个图像的直方图特性来实现全局阈值T的自动选取，此为可以成功运行与matlab上的代吗。(Otsu algorithm, also known as the largest inter class difference method, by statistical the histogram of the entire image characteristics to achieve the global threshold T automatically selected, which can be successfully run on the generation and MATLAB)