Visual sensitivity to two-dimensional spatial phase.
We investigate some limits to phase processing in the human visual system with two-dimensional textured images. Results indicate that, although phase sensitivity increases with contrast and energy components of the image, observers cannot discriminate between images and their 45 degrees phase-quantized versions under brief exposure and lower- (less than or equal to 30%) contrast conditions. These results seem to be frequency independent although modulated by different energy levels at each two-dimensional frequency band. Finally, we have analyzed some past texture-discrimination results that occur under identical amplitude-spectra conditions. Here also phase-quantization differences seem to constitute an adequate explanation of discrimination performance.
D006801:Humans; D013028:Space Perception / Q000502:physiology*; D014792:Visual Acuity