对图像进行直方图均衡，计算以下参数：概率非零灰度数，概率非零灰度中最大概率、最小概率、最大最小概率之比-The image histogram equalization, calculate the following parameters: the probability of non-zero number of gray, compared with a non-zero probability that the maximum probability of gray, the minimum probability, the probability of the maximum and minimum