Contrast-limited adaptive histogram equalization (CLAHE)
CLAHE operates on small regions in the image, called tiles,
rather than the entire image. adapthisteq
calculates the contrast
transform function for each tile individually. Each tile's contrast is enhanced, so that
the histogram of the output region approximately matches the histogram specified by the
'
Distribution
'
value. The
neighboring tiles are then combined using bilinear interpolation to eliminate
artificially induced boundaries. The contrast, especially in homogeneous areas, can be
limited to avoid amplifying any noise that might be present in the image.
[1] Zuiderveld, Karel. “Contrast Limited Adaptive Histograph Equalization.” Graphic Gems IV. San Diego: Academic Press Professional, 1994. 474–485.