An On-line Sketch Recognition Algorithm for Composite Shape
Existing sketch recognition algorithms are mainly on recognizing single segments or simple geometric objects (such as rectangles) in a stroke. We present in this paper an on-line sketch recognition algorithm for composite shapes. It can recognize single shape segments such as straight line, polygon, circle, circular arc, ellipse, elliptical arc, hyperbola, and parabola curves in a stroke, as well as any composition of these segments in a stroke. Our algorithm first segments the stroke into multi-segments based on a key point detection algorithm. Then we use “combination” fitting method to fit segments in sequence iteratively. The algorithm is already incorporated into a hand sketching based modeling prototype, and experiments show that our algorithm is efficient and well suited for real time on-line applications.
KeywordsConic Segment Pass Scanning High Curvature Point Composite Shape Simple Geometric Object
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