Contrast limited adaptive histogram equalization
Summary
Applies the matlab command adapthisteq® to reduce contrast differences throughout
the image. From the matlab documentation:
CLAHE operates on small regions in the image, called tiles, rather than the entire image. Each tile's contrast is enhanced, so that the histogram of the output region approximately matches the histogram specified by the 'Distribution' parameter. 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
Assumptions
The method assumes 2D images in grayscale
Parameters
Parameter: Enhancement limit
- Real scalar in the range [0 1] that specifies a contrast enhancement limit. Higher numbers result in more contrast.
- units [positive real value]
- recommended range: [0.01 0.05]
Parameter: Enhancement width
- Discribes the size of the tiles used by the clahe method
- units [pixels]
- recommended range [20 30]