Perception of shape from shading

  title={Perception of shape from shading},
  author={Vilayanur S. Ramachandran},
The human visual system can rapidly and accurately derive the three-dimensional orientation of surfaces by using variations in image intensity alone1–5.This ability to perceive shape from shading is one of the most important yet poorly understood aspects of human vision. Here we present several findings which may help reveal computational mechanisms underlying this ability. First, we find that perception of shape from shading is a global operation which assumes that there is only one light… 
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