The IBM RT07 Evaluation Systems for Speaker Diarization on Lecture Meetings

We present the IBM systems for the Rich Transcription 2007 (RT07) speaker diarization evaluation task on lecture meeting data. We first overview our baseline system that was developed last year, as part of our speech-to-text system for the RT06s evaluation. We then present a number of simple schemes considered this year in our effort to improve speaker diarization performance, namely: (i) A better speech activity detection (SAD) system, a necessary pre-processing step to speaker diarization; (ii) Use of word information from a speaker-independent speech recognizer; (iii) Modifications to speaker cluster merging criteria and the underlying segment model; and (iv) Use of speaker models based on Gaussian mixture models, and their iterative refinement by frame-level re-labeling and smoothing of decision likelihoods. We report development experiments on the RT06s evaluation test set that demonstrate that these methods are effective, resulting in dramatic performance improvements over o...

• Type: Conference
• Year: 2007
• Where: CLEAR
• Authors: Jing Huang, Etienne Marcheret, Karthik Visweswariah, Gerasimos Potamianos
• Keywords: Biometrics, CLEAR 2007, Speaker Cluster, Speaker Diarization, Speaker Error