Shape and Source from Shading
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چکیده
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A smooth object depicted in a photographwill often exhibit brightness variation, or shading. Various computational techniques have been developed that perform reasonably well in inferring shape from shading. However, these techniques typically require substantial prerequisite information if they are to evolve an estimate of surface shape. It is therefore interesting to consider how depth might ...
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The human visual system has a remarkable ability to interpret smooth patterns of light and shade on a surface in terms of 3-D surface geometry. Classical studies of shape{ from{shading have assumed that surface luminance depends on the local surface orientation. This classical shading model holds, for example, on a sunny day. A common situation in which the classical model fails to hold, howeve...
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For over thirty years researchers have been trying to solve the shape from shading problem of determining 3D shape from a single image with a single light source. The basic problem of determining shape from shading is made more difficult due to challenges of light orientation, camera type, ambiguity, multiple materials, and specular highlights. This paper shows how some of these challenges can ...
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