Do it with the GIMPLUT (Look-Up Tables Effects)Gamma CorrectionConcept

3.2.1. Concept

If we assume that the maximal colour value is 1 and the minimal is 0, then by applying a function of x ** (1/gamma) to every pixel we will modify the histogram while not overflowing from the image boundaries (which cannot be said on brightness and contrast manipulations).

The more positive the Gamma is the brighter the resultant image will be.

Written by Shlomi Fish