Smooth Regrading of Discretized Data

Kautsky, J. and Nichols, N. ORCID: https://orcid.org/0000-0003-1133-5220 (1982) Smooth Regrading of Discretized Data. SIAM Journal on Scientific and Statistical Computing, 3 (2). pp. 145-159. ISSN 0196-5204 doi: 10.1137/0903010

Abstract/Summary

Methods for producing nonuniform transformations, or regradings, of discrete data are discussed. The transformations are useful in image processing, principally for enhancement and normalization of scenes. Regradings which “equidistribute” the histogram of the data, that is, which transform it into a constant function, are determined. Techniques for smoothing the regrading, dependent upon a continuously variable parameter, are presented. Generalized methods for constructing regradings such that the histogram of the data is transformed into any prescribed function are also discussed. Numerical algorithms for implementing the procedures and applications to specific examples are described.