Simultaneous Speech Recognition and Speaker Diarization for Monaural Dialogue Recordings with Target Speaker Acoustic Models
This paper investigates the use of target speaker automatic speech recognition (TS ASR) for simultaneous speech recognition and speaker diarization of single channel dialogue recordings. TS ASR is a technique to automatically extract and recognize only the speech of a target speaker given a short sample utterance of that speaker. One obvious drawback of TS ASR is that it cannot be used when the speakers in the recordings are unknown because it requires a sample of the target speakers in advance of decoding. To remove this limitation, we propose an iterative method, in which (i) the estimation of speaker embeddings and (ii) TS ASR based on the estimated speaker embeddings are alternately executed. We evaluated the proposed method by using very challenging dialogue recordings in which the speaker overlap ratio was over 20% We confirmed that the proposed method significantly reduced both the word error rate (WER) and diarization error rate (DER) Our proposed method combined with i vector speaker embeddings ultimately achieved a WER that differed by only 2.1 from that of TS ASR given oracle speaker embeddings. Furthermore, our method can solve speaker diarization simultaneously as a by product and achieved better DER than that of the conventional clustering based speaker diarization method based on i vector.
2019 IEEE Automatic Speech Recognition and Understanding Workshop (ASRU)