颜色空间转换RGB2HSI HSI = RGB2HSI(RGB) converts an RGB image to HSI. The input image is assumed to be of size M-by-N-by-3, where the third dimension accounts for three image planes: red, green, and blue, in that order. If all RGB component images are equal, the HSI conversion is undefined. The input image can be of class double (w ith values in the range [0, 1]), uint8, or uint16. ith values in the range [0, 1]), uint8, or uint16.