Currently I am reading Principal Component Analysis-Based Low-Light Image Enhancement Using Reflection Model. That article proposes a way for obtaining the
illumination coefficient of the original image (). This is a quotation from it, after extracting
Now I want to know:
- What is the meaning of , while
255is the maximum possible value for intensity and
K >= 0? I think in image processing it is always
255. So why isn't its constant value written?
- How is
Fechnerlaw? I see that law says: is the minimum gray level difference which may be discriminated by the human eye when the brightness level is
I. For this question a link to any relative resource which demonstrates how this equation is obtained, is very helpful.