读取BMP 8bit文件(size n1*n2)，输出整个文件[n1]*[n2]的像素值,像素值的范围0-255,并统计每个像素质的数量-BMP 8bit file read (size n1* n2), the output document as a whole [n1]* [n2] the pixel value, pixel value range of 0-255, and the quality of statistics like the number of each