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Tree Search Methods

Basic approach:

 

Fig. 51 Interpretation tree

How do we perform matching?

We can reduce the computational overheads by employing some local geometric constraints to prune the tree further.

These are:

For Edges we could employ:

Distance Constraint
-- The length of the sensed edge must be less than or equal to the length of the model edge under consideration.
Angle Constraint
-- The angle between two adjacent sensed edges must agree with that between the two corresponding matched model edges.
Direction Constraint
-- Let tex2html_wrap_inline3774 represent the range of vectors from any point on sensed edge a to any point on sensed edge b. In an interpretation which respectively pairs sensed edges a and b with model edges i and j, this range of vectors must be compatible with the range of vectors produced by i and j.

For Surface we could employ:


next up previous
Next: Relaxation Labelling Methods Up: Model Based Recognition Previous: Model Based Recognition

tex2html_wrap_inline2984 David Marshall 1994-1997