Locality enhanced dynamic biasing and sampling strategies for contextual ASR

Author:

Md Asif Jalal, Pablo Peso Parada, George Pavlidis, Vasileios Moschopoulos, Karthikeyan Saravanan, Chrysovalantis-Giorgos Kontoulis, Jisi Zhang, Anastasios Drosou, Gil Ho Lee, Jungin Lee, Seokyeong Jung

Keyword:

Electrical Engineering and Systems Science, Audio and Speech Processing, Audio and Speech Processing (eess.AS), Computation and Language (cs.CL), Sound (cs.SD)

journal:

date:

2024-01-23 00:00:00

Abstract

Automatic Speech Recognition (ASR) still face challenges when recognizing time-variant rare-phrases. Contextual biasing (CB) modules bias ASR model towards such contextually-relevant phrases. During training, a list of biasing phrases are selected from a large pool of phrases following a sampling strategy. In this work we firstly analyse different sampling strategies to provide insights into the training of CB for ASR with correlation plots between the bias embeddings among various training stages. Secondly, we introduce a neighbourhood attention (NA) that localizes self attention (SA) to the nearest neighbouring frames to further refine the CB output. The results show that this proposed approach provides on average a 25.84% relative WER improvement on LibriSpeech sets and rare-word evaluation compared to the baseline.

PDF: Locality enhanced dynamic biasing and sampling strategies for contextual ASR.pdf