Contents

• List of Tables
• List of Figures
• Introduction
  • Context and Motivations of this Thesis
  • Definition of the Thesis Objectives
  • Outline of the Thesis
  
  
• State of the art
  • Acoustic Features for Speaker Diarization
  • Speaker Segmentation
    • Metric-Based Segmentation
    • Non Metric-Based Segmentation
  • Speaker Diarization
    • Hierarchical Clustering Techniques
    • Other Clustering Techniques
    • Use of Support Information in Diarization
  • Speaker Diarization in Meetings
    • Current Meeting Room Research Projects
    • Databases
    • NIST RT Speaker Diarization Systems for Meetings
  • Multichannel Acoustic Enhancement
    • Introduction to Acoustic Array Processing
    • Microphone Array Beamforming
    • Time Delay of Arrival Estimation
  
  
• Speaker Diarization: from Broadcast News to Meetings
  • The ICSI Broadcast News System
    • Speech/non-Speech Detection and Parameters Extraction
    • Clusters Initialization and Acoustic Modeling
    • Clusters Comparison, Pruning and Clusters Merging
    • Stopping Criterion and System Output
  • Analysis of Differences from Broadcast News to Meetings
    • Input Data Analysis: Broadcast News versus Meetings
    • Summary of Differences and Proposed Changes
  • Robust Speaker Diarization System for Meetings
    • Acoustic Signal Enhancement
    • Single Channel System Frontend
    • Speaker Clusters and Models Initialization
    • Clusters Merging and System Output
  
  
• Acoustic Modeling Algorithms for Speaker Diarization in Meetings
  • Speech/Non-Speech Algorithm
    • Energy-Based Speech/non-Speech Detector with Variable threshold
    • Model-based Speech/Non-Speech Decoder
    • Hybrid Speech/non-Speech Detection
  • Speaker Clusters Description and Modeling
    • Friends-and-Enemies Initialization
    • Clusters and Models Complexity Selection
    • Acoustic Modeling without Time Restrictions
  • Cluster Purification Algorithms
    • Frame-Level Cluster Purification
    • Segment-Level Cluster Purification
  
  
• Multichannel Processing for Meetings
  • Multichannel Acoustic Beamforming for Meetings
    • Meeting Room Microphone Array Characteristics
    • Filter-and-Sum Beamforming
  • Multichannel Acoustic Beamforming System Implementation
    • Individual Channels Signal Enhancement
    • Meeting Information Extraction
    • TDOA Values Selection
    • Output Signal Generation
  • Use of the Estimated Delays for Speaker Diarization
    • TDOA Modeling and Features Fusion
    • Automatic Features Weight Estimation
  
  
• Experiments
  • Meetings Domain Experiments Setup
    • Baseline Systems
    • Databases
    • Evaluation Metrics
    • Reference Segmentation Selection and Calculation
  • Experiments from Broadcast News to Meetings
  • Speech/Non-Speech Detection Block
  • Acoustic Beamforming Experiments
    • Baseline System Analysis
    • Reference Channel Estimation Analysis
    • TDOA Post-Processing Analysis
    • Signal Output Algorithms Analysis
    • Use of the Beamformed Signal for ASR
  • Speaker Diarization Module Experiments
    • Individual Algorithms Performance
    • Algorithms Agglomeration Performance
  • Overall Experiments and Analysis of Results
  
  
• NIST Evaluations in Speaker Diarization
  • NIST Rich Transcription Evaluations in Speaker Diarization for Meetings
    • RT05s and RT06s Evaluation Conditions
    • Methodology of the Evaluations
    • Data used on the Speaker Diarization Evaluations
  • ICSI Participation in the RT Evaluations
    • Participation in the 2005 Spring Rich Transcription Evaluation
    • Participation in the 2006 Spring Rich Transcription Evaluation
  • Pros and Cons of the NIST Evaluations
  
  
• Conclusions
  • Overall Thesis Final Review
  • Review of Objectives Completion
  • Possible Future Work Topics
  
  
• BIC Formulation for Gaussian Mixture Models
• Rich Transcription evaluation datasets
• Bibliography

Bibliography