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Offline Recognition of Unconstrained Handwritten Texts Using HMMs and Statistical Language Models
June 2004 (vol. 26 no. 6)
pp. 709-720

Abstract—This paper presents a system for the offline recognition of large vocabulary unconstrained handwritten texts. The only assumption made about the data is that it is written in English. This allows the application of Statistical Language Models in order to improve the performance of our system. Several experiments have been performed using both single and multiple writer data. Lexica of variable size (from 10,000 to 50,000 words) have been used. The use of language models is shown to improve the accuracy of the system (when the lexicon contains 50,000 words, the error rate is reduced by \sim 50 percent for single writer data and by \sim 25 percent for multiple writer data). Our approach is described in detail and compared with other methods presented in the literature to deal with the same problem. An experimental setup to correctly deal with unconstrained text recognition is proposed.

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Index Terms:
Offline cursive handwriting recognition, statistical language models, N\hbox{-}{\rm{grams}}, continuous density Hidden Markov Models.
Citation:
Alessandro Vinciarelli, Samy Bengio, Horst Bunke, "Offline Recognition of Unconstrained Handwritten Texts Using HMMs and Statistical Language Models," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 26, no. 6, pp. 709-720, June 2004, doi:10.1109/TPAMI.2004.14
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