Conference Paper

An efficient beam pruning with a reward considering the potential to reach various words on a lexical tree

User Interface Lab., KDDI R& D Labs. Inc., Fujimino, Japan
DOI: 10.1109/ICASSP.2010.5495098 Conference: Acoustics Speech and Signal Processing (ICASSP), 2010 IEEE International Conference on
Source: IEEE Xplore

ABSTRACT This paper presents an efficient frame-synchronous beam pruning for automatic speech recognition. With conventional beam pruning, hypotheses that have a greater potential to reach various words on a lexical tree are likely to be pruned out, since this potential is not taken into account. To make the beam pruning less restrictive for hypotheses with a greater potential and vice versa, the proposed method adds a reward as a monotonically increasing function of the number of reachable words from the node where a hypothesis stays on a lexical tree, to the likelihood of the hypothesis. The reward is designed not to collapse the ASR probabilistic framework. The proposed method reduces the processing time from 30% to 70% for grammar-based tasks. For a language-model-based dictation task, it also causes an additional reduction from the processing time of the beam pruning with the language model look-ahead technique.

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    INTERSPEECH 2005 - Eurospeech, 9th European Conference on Speech Communication and Technology, Lisbon, Portugal, September 4-8, 2005; 01/2005
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    The 3rd International Conference on Spoken Language Processing, ICSLP 1994, Yokohama, Japan, September 18-22, 1994; 01/1994
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