The influence of speech activity detection and overlap on speaker diarization for meeting room recordings

Abstract This paper addresses the problem of speaker diarization inthe specific context of meeting room recordings which of-ten involve a high degree of spontaneous speech with largeoverlapped speech segments, speaker noise (laughs, whispers,coughs, etc.) and very short speaker turns. A large variabilityin signal quality has brought an additional level of complexity.This paper investigates the effects of speech activity detectionand overlapped speech through speaker diarization experimentsconducted on the NIST RT’05 and RT’06 data sets. Resultsindicate that our system is highly sensitive to the shape of theinitial segmentation and that, perhaps surprisingly, perfect ref-erences can even degrade performance. Finally we propose adirection for future research to incorporate confidence valuesaccording to acoustic attributes in order to unify what is cur-rently a somewhat disjointed approach to speaker diarization. Index Terms : speaker diarization, meeting room, speech activ-ity detection, overlapped speech.