Nicolai Petkov

Gabor filtering augmented with surround inhibition for improved contour detection by texture suppression

HUNGARIANS IN VISUAL SCIENCE AND ART ^ Adolf von Szily (1848 ^ 1920) and visual science N J Wade, B Gillamô, W H Ehrenstein1⁄2, G Koväcs#, Z VidnyänszkyÁ (Department of Psychology, University of Dundee, Perth Road, Dundee DD1 4HN, Scotland, UK; ô School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia; 1⁄2 Institut fu« r Arbeitsphysiologie, Universita« t Dortmund, Ardeystrasse 67, D 44139 Dortmund, Germany; #Center for Cognitive Sciences, Budapest Technical University, Mua egyetem-rkp. 3-9, H 1111 Budapest, Hungary; ÁNeurobiology Research Group, Hungarian Academy of Sciences, Semmelweis University, H 1094 Budapest, Hungary; e-mail: n.j.wade@dundee.ac.uk) Adolf von Szily was born in Budapest, studied medicine in Vienna, and returned to Budapest to practice ophthalmology. In addition to his ophthalmological research, he explored a range of topics in visual science, including motion aftereffects, fluttering hearts, and stereoscopic depth perception. He demonstrated that a physically stationary pattern that appears to move as a consequence of surround motion yields a motion aftereffect when the surround motion ceases. This close relationship between simultaneous and successive motion contrast has assumed considerable theoretical significance. He explored interactions between colour, space, and motion in the fluttering-hearts phenomenon. His paper on stereoscopic depth, first given in 1894 at a conference in Vienna, was published posthumously by his son, Aurel (an even more famous ophthalmologist). It described a novel stereoscopic technique using all-black figures (silhouettes) with certain monocular appendages; they form subjective contours in front of the binocular shape or amodal completions behind it. This technique anticipated a number of modern findings and the recent interest in Da Vinci stereopsis. Despite these farsighted investigations, von Szilys work has been sadly neglected within visual science.