“…Nonparametric statistical methods for the analysis of discontinuities in images have been studied in a number of papers (Tsybakov, 1989(Tsybakov, , 1991(Tsybakov, , 1994Korostelev, 1991;Korostelev andTsybakov, 1992, 1993a,b;Carlstein and Krishnamoorthy, 1992;Müller and Song, 1994a,b;Rudemo and Stryhn, 1994a,b;Freidlin and Korostelev, 1995;Mammen and Tsybakov, 1995;Jacob and Suquet, 1996;Donoho, 1997;Hall and Raimondo, 1997a,b;Qiu, 1997; Qiu and Yandell, 1997; Chu et al, 1998;Polzehl and Spokoiny (1998a,b)). These papers deal with statistical estimation of discontinuity contours (edges) in images.…”