Human perception of local shape from shading under variable lighting
نویسندگان
چکیده
It is commonly believed that humans exhibit lighting invariant object recognition. Here we present psychophysical evidence to the contrary. We examine the perception of qualitative local shape from shading and find that significant variations occur as a function of the lighting. These variations have two logically distinct causes: first, there are inherent ambiguities between shape and shading that depend on lighting; second, the visual system makes prior assumptions that can lead to systematic errors under different lighting. Using computer graphics psychophysics, we isolate and measure these lighting-dependent variations in shape perception.
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