Abstract
We investigate the perception of three-dimensional structure from shading when surface texture is given, specifically to reveal the interaction of shape-from-shading and contour/boundary that segregates figure and ground. The stimuli we utilized consist of circular regions (figure) with simple gradation, superimposed with white-noise (WN) or random-dot (Rnd) texture. We carried out psychophysical experiments using the stimuli and obtained the following results: (1) the 3D perception is improved when the mean illuminance of figure and ground is identical, (2) the perception is improved when WN is superimposed to figure that is darker than ground, (4) the perception is improved if figure's contour is drawn with a darker line when figure is brighter than ground. These results suggest that the discrimination of figure from ground is crucial for the perception of shape-from-shading.
