Contrast matching of two-dimensional compound gratings.
The contrast of a two-dimensional compound grating consisting of 2, 3 or 4 components with the same spatial frequency but different orientations was matched to the contrast of a simple cosine grating. At all spatial frequencies and contrast levels studied the stimuli which matched in apparent contrast had nearly equal r.m.s. (root-mean-square) but different Michelson contrasts. Thus, matching was based on r.m.s. contrast which takes into account the distribution of luminance levels in the stimulus. A matched filter provides a simple model to explain the contrast matching results.
Tiippana
K
K
Department of Vision Sciences, University of Aston, Birmingham, England.
Näsänen
R
R
Rovamo
J
J
D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008959:Models, Neurological; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012399:Rotation