Material and shape perception based on two types of intensity gradient information
Fig 24
Demonstration of detecting albedo changes based on the intensity gradient.
(a) Veridical highlights have little effect on the direction map, i.e., the map for the veridical highlight was similar to that for the matte one. In contrast, inconsistent highlights mark an abrupt change in the direction map. (b) When one of the intrinsic image decomposition algorithms [58] was applied to the object images with veridical and inconsistent highlights (left), even for the uniform albedo image with veridical highlights it incorrectly detects the highlights as different albedos. The estimated albedo images are shown at the bottom of the figure. In contrast, when it was applied to the slope-normalized image (right), the image with veridical highlights can be regarded as a uniform albedo.