Abstract
Contextual biasing supplies an ASR system with a list of expected words at inference time, but existing methods rely on word boundaries that Japanese and Chinese do not provide. We present a boundary-free biasing decoder for frozen public CTC models, built on a character-level Aho-Corasick automaton, with no training and no second pass. Two evidence-based mechanisms replace the boundary: a depth-adaptive gate that sets how hard to push from match depth, and reading-space matching for when the audio is right but the characters are wrong. On Aishell-1 NE's hard R1 subset we reach 66.5% recall, above the trained CLAS baseline (64%), transferring to WenetSpeech and to a second architecture without retuning. We release the first open Japanese contextual-biasing benchmark, where biasing lifts rare-word recall by 25 points at precision above 97%, and still by 19 and 22 points against 1,000-word lists.
Keywords
Publication details
- Journal
- Not available
- Open access
- Green open access
Cite this article
APA 7
Huzaifah, M., Pan, Y., Yeo, Z., Bai, N., & Yang, G. (2026). Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages. https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages
MLA 9
Huzaifah, Muhammad, et al. "Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages." https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages.
Chicago (author–date)
Huzaifah, Muhammad, Yu Pan, Zachary Yeo, Ningjie Bai, and Guangzhao Yang. 2026. "Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages." https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages.
Harvard
Huzaifah, M., Pan, Y., Yeo, Z., Bai, N. and Yang, G. (2026) 'Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages', Available at: https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages.
Vancouver
Huzaifah M, Pan Y, Yeo Z, Bai N, Yang G. Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages. https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages
IEEE
M. Huzaifah, Y. Pan, Z. Yeo, N. Bai, and G. Yang, "Boundary-Free Contextual Biasing: Depth-Adaptive Gating and Reading-Space Matching for Unsegmented Languages," https://omanscience.com/en/articles/boundary-free-contextual-biasing-depth-adaptive-gating-and-reading-space-matching-for-unsegmented-languages.