Issue No. 04 - April (1979 vol. 1)
Paul J. Nahin , Department of Electrical and Computer Engineering, University of New Hampshire, Durham, NH 03824.
Frei has recently introduced a new technique (histogram hyperbolization) for image enhancement by the manipulation of the picture brightness levels. An alternative derivation of Frei's result, both simpler and more general, is presented.
Paul J. Nahin, "A Simplified Derivation of Frei's Histogram Hyperbolization for Image Enhancement", IEEE Transactions on Pattern Analysis & Machine Intelligence, vol. 1, no. , pp. 414-415, April 1979, doi:10.1109/TPAMI.1979.4766952