Empirical Evaluation of Computational Models of Lightness Perception

Abstract

Lightness of a surface depends not only on its physical characteristics, but also on the properties of the surrounding context. As a result, varying the context can significantly alter surface lightness, an effect exploited in many lightness illusions. Computational models can produce outcomes similar to human illusory percepts, allowing for demonstrable assessment of the applied mechanisms and principles. We tested 8 computational models on 13 typical displays used in lightness research (11 Illusions and 2 Mondrians), and compared them with results from human participants (N = 85). Results show that HighPass and MiR models predict empirical results for simultaneous lightness contrast (SLC) and its close variations. ODOG and its newer variants (ODOG-2 and L-ODOG) in addition to SLC displays were able to predict effect of White’s illusion. RETINEX was able to predict effects of both SLC displays and Dungeon illusion. Dynamic decorrelation model was able to predict obtained effects for all tested stimuli except two SLC variations. Finally, FL-ODOG model was best at simulating human data, as it was able to predict empirical results for all displays, bar the Reversed contrast illusion. Finally, most models underperform on the Mondrian displays that represent most natural stimuli for the human visual system.

Simple Assumptions to Improve Markov Illuminance and Reflectance

“…Additionally, it correctly predicts the absence of the effect in Howe ( 2001)'s control figure (Figure 8C), which should be predicted to yield an illusion by models that depend on the processing of T-junctions (Todorović, 1997). Failures in the prediction of reverse-contrast phenomena have been a major weakness of the original MIR (Murray, 2020;Nedimović et al, 2021), but this study proved that it is possible for the MIR framework to overcome this weakness.…”

“…We present a modified version of MIR that can account for different types of lightness phenomena. The current version of MIR (Murray, 2020) does not predict reverse contrasts (Nedimović et al, 2021), where target areas neighboring dark regions appear darker than an equiluminant target neighboring bright regions (Bressan, 2001;Agostini and Galmonte, 2002a;Economou et al, 2015). White's effect is one of the most famous reverse contrasts (White, 1981(White, , 1979.…”