Veridicality of three-dimensional shape perception predicted from amplitude spectra of natural textures

We show that the amplitude spectrum of a texture pattern, regardless of its phase spectrum, can be used to predict whether the pattern will convey the veridical three-dimensional (3-D) shape of the surface on which it lies. P atterns from the Brodatz collection of natural textures were overlaid on a flat surface that was then corrugated in depth and projected in perspective . Perceived ordinal shapes, reconstructed from a series of local relative d epth judgments, showed that only about a, third. of the patterns conveyed v eridical shape. The phase structure of each pattern was then randomized. Si mulated concavities and convexities were presented for both the Brodatz and the phase-randomized patterns in a global shape identification task. The c oncordance between the shapes perceived from the Brodatz patterns and their phase-randomized versions was 80-88%, showing that the capacity for a patt ern to correctly convey concavities and convexities is independent of phase information and that the amplitude spectrum contains all the information r equired to determine whether a pattern will convey veridical 3-D shape., A measure of the discrete oriented energy centered on the axis of maximum cur vature was successful in identifying textures that convey veridical shape. (C) 2001 Optical Society of America.