Sound Capture and Processing: Practical Approaches

Foreword.

Preface.

Acknowledgements.

1 Introduction.

1.1 The Need for, and Consumers of, Sound Capture and Audio Processing Algorithms.

1.2 Typical Sound Capture System.

1.3 The Goal of this Book and its Target Audience.

1.4 Prerequisites.

1.5 Book Structure.

1.6 Exercises.

2 Basics.

2.1 Noise: Definition, Modeling, Properties.

2.2 Signal: Definition, Modeling, Properties.

2.3 Classification: Suppression, Cancellation, Enhancement.

2.4 Sampling and Quantization.

2.5 Audio Processing in the Frequency Domain.

2.6 Bandwidth Limiting.

2.7 Signal-to-Noise-Ratio: Definition and Measurement.

2.8 Subjective Quality Measurement.

2.9 Other Methods for Quality and Enhancement Measurement.

2.10 Summary.

Bibliography.

3 Sound and Sound Capturing Devices.

3.1 Sound and Sound Propagation.

3.2 Microphones.

3.3 Omnidirectional and Pressure Gradient Microphones.

3.4 Parameter Definitions.

3.5 First-order Directional Microphones.

3.6 Noise-canceling Microphones and the Proximity Effect.

3.7 Measurement of Microphone Parameters.

3.8 Microphone Models.

3.9 Summary.

Bibliography.

4 Single-channel Noise Reduction.

4.1 Noise Suppression as a Signal Estimation Problem.

4.2 Suppression Rules.

4.3 Uncertain Presence of the Speech Signal.

4.4 Estimation of the Signal and Noise Parameters.

4.5 Architecture of a Noise Suppressor.

4.6 Optimizing the Entire System.

4.7 Specialized Noise-reduction Systems.

4.8 Practical Tips and Tricks for Noise Suppression.

4.9 Summary.

Bibliography.

5 Sound Capture with Microphone Arrays.

5.1 Definitions and Types of Microphone Array.

5.2 The Sound Capture Model and Beamforming.

5.3 Terminology and Parameter Definitions.

5.4 Time-invariant Beamformers.

5.5 Channel Mismatch and Handling.

5.6 Adaptive Beamformers.

5.7 Microphone-array Post-processors.

5.8 Specific Algorithms for Small Microphone Arrays.

5.9 Summary.

Bibliography.

6 Sound Source Localization and Tracking with Microphone Arrays.

6.1 Sound Source Localization.

6.2 Sound Source Localization from a Single Frame.

6.3 Post-processing Algorithms.

6.4 Practical Approaches and Tips.

6.5 Summary.

Bibliography.

7 Acoustic Echo-reduction Systems.

7.1 General Principles and Terminology.

7.2 LMS Solution for Acoustic Echo Cancellation.

7.3 NLMS and RLS Algorithms.

7.4 Double-talk Detectors.

7.5 Non-linear Acoustic Echo Cancellation.

7.6 Acoustic Echo Suppression.

7.7 Multichannel Acoustic Echo Reduction.

7.8 Practical Aspects of the Acoustic Echo-reduction Systems.

7.9 Summary.

Bibliography.

8 De-reverberation.

8.1 Reverberation and Modeling.

8.2 De-reverberation via De-convolution.

8.3 De-reverberation via Suppression.

8.4 De-reverberation with Multiple Microphones.

8.5 Practical Recommendations.

8.6 Summary.

Bibliography.

Index.