Gradient independent translation via differential morphology
A new multi-scale image enhancement mechanism is presented. Derived from the differential representation of the morphological filters, it approximates a median filter and alleviates many of the image blotching and noise preserving characteristics of morphological filtering. In one-dimension, the process is shown to be idempotent and to converge. In two dimensions, experimental results demonstrate convergence and display the ability to remove impulsive noise. Gradient independent translation avoids the two dimensional convergence problems of the median filter and does not involve the expensive rank-ordering of pixel intensities. Describing a scale space with median filter characteristics, it provides a multi-scale analysis method suitable for compression, coding, and feature extraction.