How to calculate NDI Index

Hello,

I have to calculate the NDI (Normalized difference index) according to the formula: NDI = 128*(((G-R)/(G+R))+1)

This index is applied to all pixels of the image, giving values between 1 and +1, but to display the image, these values must be between 0 and 255.

Can someone please explain and help me how to do this?

Answer 1

[Stephan]

NDI_new = uint8(rescale(NDI, 0, 255));

[MaxM]

Thank you for your answer about the rescale. First, how can I calculate the NDI for each pixel of my image ?

[Stephan]

What are G and R - green and red values? Or what is meant?