The IBM Rich Transcription 2007 Speech-to-Text Systems for Lecture Meetings

The paper describes the IBM systems submitted to the NIST Rich Transcription 2007 (RT07) evaluation campaign for the speechto-text (STT) and speaker-attributed speech-to-text (SASTT) tasks on the lecture meeting domain. Three testing conditions are considered, namely the multiple distant microphone (MDM), single distant microphone (SDM), and individual headset microphone (IHM) ones – the latter for the STT task only. The IBM system building process is similar to that employed last year for the STT Rich Transcription Spring 2006 evaluation (RT06s). However, a few technical advances have been introduced for RT07: (a) better speaker segmentation; (b) system combination via the ROVER approach applied over an ensemble of systems, some of which are built by randomized decision tree state-tying; and (c) development of a very large language model consisting of 152M n-grams, incorporating, among other sources, 525M words of web data, and used in conjunction with a dynamic decoder. These advan...

• Type: Conference
• Year: 2007
• Where: CLEAR
• Authors: Jing Huang, Etienne Marcheret, Karthik Visweswariah, Vit Libal, Gerasimos Potamianos
• Keywords: Biometrics, CLEAR 2007, Distant Microphone, Evaluation, Large Language Model