Segment Sequence-Based Handwritten Expression Recognition

A computer-readable medium having computer-executable instructions that, when executed on one or more processors, perform operations comprising:

• generating a symbol graph to represent a plurality of strokes associated with a handwritten expression, the symbol graph including a plurality of nodes, each node corresponding to a combination of a stroke and a candidate symbol for that stroke;
• determining a plurality of segment sequences by selecting a number of symbol sequences from the symbol graph and combining symbol sequences having a same segmentation;
• and
• performing a structure analysis on at least a subset of the segment sequences to determine a set of hypotheses for the handwritten expression.

A tablet personal computer comprising:

• a processor;
• an input mechanism configured to receive a handwritten expression;
• and
• a plurality of executable instructions configured to be operated by the processor and to program the computing device to:
• generate a symbol graph to represent a plurality of strokes associated with a handwritten expression, the symbol graph including a plurality of nodes, each node corresponding to a combination of a stroke and a candidate symbol for that stroke;
• perform a tree search on the symbol graph to score symbol sequences comprised of the nodes;
• generate a segment graph based on the symbol graph by combining nodes associated with a same stroke if strokes of their preceding nodes are the same, the combining including adding a candidate symbol associated with one node as an attribute of another node with which the one node is being combined and deleting the one node and its incoming and outgoing edges after the adding;
• and
• perform a structure analysis on at least a subset of a plurality of segment sequences represented by the segment graph to determine a set of hypotheses for the handwritten expression, wherein the subset of the segment sequences are the sequences having the highest scores.