Extraction of 3D shape from optic flow: a geometric approach
نویسندگان
چکیده
We derive several measures of 3D shape directly from the velocity field generated by a rigid curved surface patch under perspective projection. We use invariance under rotation of the image plane to decompose the velocity field in differential invariants. From a combination of these invariants we construct an approximation to the absolute value of the shape index, to the curvedness and to the principal direction. We show the effect of these approximations to be small for a field of view of 6 deg.
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