g = gscale(f, method, low, high)

其中，f是将被标度的图像，method的有效值为 full8 和 full16 ，前者将输出标度为全范围[0, 255]，后者将输出标度为全范围[0, 65535]。若使用这两个有效值之一，则可在两种变换中省略参数low与high。-g = gscale (f, method, low, high) where, f is an image to be scaled, method of valid values ​ ​ ' full8'　and ' full16' , the former for the full scale output range [0, 255], The latter is the full scale output range [0, 65535]. If you use one of these two valid values, you can omit the parameter in both low and high transformation.