Contrast image correction method

A method for contrast enhancement is proposed. The
algorithm is based on a local and image-dependent exponential correction.
The technique aims to correct images that simultaneously
present overexposed and underexposed regions. To prevent halo
artifacts, the bilateral filter is used as the mask of the exponential
correction. Depending on the characteristics of the image (piloted by
histogram analysis), an automated parameter-tuning step is introduced,
followed by stretching, clipping, and saturation preserving
treatments. Comparisons with other contrast enhancement techniques
are presented. The Mean Opinion Score (MOS) experiment
on grayscale images gives the greatest preference score for our
algorithm