Cython interface to CLAHE

This is a cython wrapper for the C code of CLAHE (Contrast Limited Adaptive Histogram Equalization), available from "Graphics Gems IV". This is an alternative to contrast-stretch, it slides a window over the image and locally stretches the contrast while respecting a constraint on authorized gradient jumps.

Example

python example.py

Raw image and simple contrast-stretch:
 

CLAHE with 2x2 window:

CLAHE with 5x5 window:

CLAHE with 20x20 window:

CLAHE with 50x50 window:

Reference

ANSI C code from the article
"Contrast Limited Adaptive Histogram Equalization"
by Karel Zuiderveld, karel@cv.ruu.nl
in "Graphics Gems IV", Academic Press, 1994