Abstract: A method for encoding handwritten symbols operates upon penstroke data received from a device capable of sampling a stylus position at discrete intervals. Each handwritten symbol is segmented into an ordered sequence of discrete strokes. An are length and initial and final tangent angles are evaluated for each of these strokes. Each stroke is encoded in the form of a parameter set comprising position coordinates of the initial and final endpoints of the stroke, the arc length, and the initial and final tangent angles. In specific embodiments of the invention, the segmentation is based, in part, on properties of the handwritten symbol when it is expressed as a curve &phgr;(s), wherein s represents arc length and &phgr; represents the net turning angle.

Abstract: A method and apparatus for reconstructing legible characters from stored data are described. For each of a plurality of handwritten strokes, a set of endpoint conditions is received. The endpoint conditions are data which define an initial and a final tangent angle for the stroke, and positions of an initial and a final endpoint of the stroke. For each set of endpoint conditions, an artificial stroke is constructed such that it satisfies the corresponding endpoint conditions and consists of at most three segments. Each of these segments consists of a straight line or an arc. Within any given stroke, lines and arcs may occur only in alternation.

Abstract: A method for encoding handwritten symbols operates upon penstroke data received from a device capable of sampling a stylus position at discrete intervals. Each handwritten symbol is segmented into an ordered sequence of discrete strokes. An arc length and initial and final tangent angles are evaluated for each of these strokes. Each stroke is encoded in the form of a parameter set comprising position coordinates of the initial and final endpoints of the stroke, the arc length, and the initial and final tangent angles. In specific embodiments of the invention, the segmentation is based, in part, on properties of the handwritten symbol when it is expressed as a curve .phi.(s), wherein s represents arc length and .phi. represents the net turning angle.

Abstract: A method is described for the automatic recognition of at least one handwritten symbol. A representation of such symbol is provided, in a data storage medium, as a sequence of one or more discrete strokes having respective initial and final endpoints, a spatial location and a tangent angle being associated with each endpoint. Representations of plural library symbols, each a prototype of a possible class to which the input symbol may be assigned, are retrieved from a data storage medium. A comparison between the input-symbol representation and each of the retrieved library symbol representations includes comparing the respective tangent angles of the input symbol with the corresponding tangent angles of at least some of the library symbols, and comparing the respective endpoint locations of the input symbol with the corresponding endpoint locations of at least some of the library symbols.