A hybrid large vocabulary handwritten word recognition system using neural networks with hidden Markov models

A.L. Koerich1, Y. Leydier2, R. Sabourin1, C.Y. Suen3
1Laboratory dE28099Imagerie, de Vision et dE28099Intelligence Artificielle, Ècole de Technologie Supérieure, Montreal, Canada
2Laboratory Reconnaissance de Formes et Vision, I.N.S.A., Villeurbanne, France
3Centre for Pattern Recognition and Machine Intelligence, Concordia University, Montreal, Canada

Tóm tắt

We present a hybrid recognition system that integrates hidden Markov models (HMM) with neural networks (NN) in a probabilistic framework. The input data is processed first by a lexicon-driven word recognizer based on HMMs to generate a list of the candidate N-best-scoring word hypotheses as well as the segmentation of such word hypotheses into characters. An NN classifier is used to generate a score for each segmented character and in the end, the scores from the HMM and the NN classifiers are combined to optimize performance. Experimental results show that for an 80,000-word vocabulary, the hybrid HMM/NN system improves by about 10% the word recognition rate over the HMM system alone.

Từ khóa

#Vocabulary #Handwriting recognition #Neural networks #Hidden Markov models #Pattern recognition #Character recognition #Character generation #Image segmentation #Viterbi algorithm #Reconnaissance

Tài liệu tham khảo

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