Material and shape perception based on two types of intensity gradient information
Fig 17
(a) The scatter plots of the perceived surface orientation between the normal and reversed Lambertian conditions. Left and right panels show the results for the tilt and slant, respectively. Each plot indicates the averaged judgment across trials within each observer for each gauge position. The circular correlation [29, 30] and Pearson’s correlation coefficients are shown in the tilt and slant panels, respectively. (b) The gauge positions in the stimulus. Red colors in each figure show the positions where the direction of the intensity gradient on the stimulus condition was the same as that on the Lambertian object. Green in each figure shows the positions where the direction of the intensity gradient on the stimulus condition was opposite to that on the Lambertian object. (c) The angular difference between the judgments on the two asperity conditions and the Lambertian condition. The horizontal axis indicates the gauge number, which is shown in the Fig 17(B).