Abstract The optimal path search is usually used to obtain the results of character segmentation and character recognition in character string recognition . In this paper, two search fashions are applied to handwritten character string recognition: character-synchronous and time-synchronous. Their performance is compared by combining different path evaluation criteria and search strategies. Moreover, a modified path evaluation criterion is proposed. The dynamic programming (DP) algorithm can find the optimal path by the proposed criterion. Experimental results of online handwritten Japanese character string recognition show that time-synchronous search is more efficient than character-synchronous search for lexicon-free character string recognition. Under the proposed path evaluation criterion, the equivalent accuracies of the segmentation and recognition to the normalized path evaluation criterion are obtained with greatly reduced search time.
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2009, Vol. 22 
