Abstract

A patch of texture A embedded in a background of texture B, is sometimes detected more easily than a same size patch of texture B embedded in a background of texture A. This phenomenon is called texture discrimination asymmetry. The perceptual texture performance asymmetry was investigated by manipulating the orientation variation of lines, the gradual change of L and + micropatterns and the frequency change in filtered random noise. Variability was shown to be a large contribution in the asymmetry, and a model using quadratic forms and signal detection theory was in qualitative agreement. An experiment with randomly oriented and fixed orientation micropatterns also showed the important role played by variability in asymmetry. The enclosing circles of micropatterns had a contribution lower than variability in asymmetry. The foreground-background area ratio and the textons were important in establishing the way of the asymmetry: classic cases of asymmetry in micropatterns were reversed by manipulating those characteristics. Discrimination, therefore asymmetry, was shown to depend on both edge and region mechanisms.