color/RGB to gray conversion via a dynamic LUT analysis

[Frederic V. Hessman]

I looked but didn't find an intelligent color/RGB to grayscale  
conversion program that would do the following:

1. put a rectangular ROI on the calibration bar (from ImageJ or placed  
within the colored image)
2. tell the conversion program that the ROI represents gray values  
from/to specific values (e.g. visible in the labelling of the  
calibration bar).
3. convert the ROI into a LUT and then extract the original grayscale  
values.

I'd call it "de-LUT-ing".

Rick

[Xiaowei Song]

Do you have any update about de-LUT analysis?