EXAMINING EDGE-BASED AND REGION-BASED TEXTURE ANALYSIS MECHANISMS

Instantaneous texture discrimination performance was examined for diff erent texture stimuli to uncover the use of edge-based and region-base d texture analysis mechanisms, Textures were composed of randomly plac ed, short, oriented line segments, Line segment orientation was chosen randomly using a Gaussian distribution (described by a mean and a sta ndard deviation), One such distribution determined the orientations on the left side of the image, and a second distribution was used for th e right side, The two textures either abutted to form an edge or were separated by a blank region, A texture difference in mean orientation led to superior discrimination performance when the textures abutted, On the other hand, when the textures differed in the standard deviatio n of the orientation distribution, performance was similar in the two conditions, These results suggest that edge-based texture analysis mec hanisms were used (i.e. were the most sensitive) in the abutting diffe rence-in-mean case, but region-based texture analysis mechanisms were used in the other three cases. (C) 1998 Elsevier Science Ltd. All righ ts reserved.