Theory and Applications of Digital Speech Processing

Cover......Page 1
Contents......Page 6
Preface......Page 10
CHAPTER 1 Introduction to Digital Speech Processing......Page 16
 1.1 The Speech Signal......Page 18
 1.2 The Speech Stack......Page 23
 1.3 Applications of Digital Speech Processing......Page 25
 1.4 Comment on the References......Page 30
 1.5 Summary......Page 32
 2.2 Discrete-Time Signals and Systems......Page 33
 2.3 Transform Representation of Signals and Systems......Page 37
 2.4 Fundamentals of Digital Filters......Page 48
 2.5 Sampling......Page 59
 Problems......Page 71
 3.1 Introduction......Page 82
 3.2 The Process of Speech Production......Page 83
 3.3 Short-Time Fourier Representation of Speech......Page 96
 3.4 Acoustic Phonetics......Page 101
 3.5 Distinctive Features of the Phonemes of American English......Page 123
 Problems......Page 125
 4.1 Introduction......Page 139
 4.2 The Speech Chain......Page 140
 4.3 Anatomy and Function of the Ear......Page 142
 4.4 The Perception of Sound......Page 148
 4.5 Auditory Models......Page 165
 4.6 Human Speech Perception Experiments......Page 173
 4.7 Measurement of Speech Quality and Intelligibility......Page 177
 4.8 Summary......Page 181
 Problems......Page 182
 5.1 The Acoustic Theory of Speech Production......Page 185
 5.2 Lossless Tube Models......Page 215
 5.3 Digital Models for Sampled Speech Signals......Page 234
 Problems......Page 243
 6.1 Introduction......Page 254
 6.2 Short-Time Analysis of Speech......Page 257
 6.3 Short-Time Energy and Short-Time Magnitude......Page 263
 6.4 Short-Time Zero-Crossing Rate......Page 272
 6.5 The Short-Time Autocorrelation Function......Page 280
 6.6 The Modified Short-Time Autocorrelation Function......Page 288
 6.7 The Short-Time Average Magnitude Difference Function......Page 290
 6.8 Summary......Page 292
 Problems......Page 293
 7.1 Introduction......Page 302
 7.2 Discrete-Time Fourier Analysis......Page 304
 7.3 Short-Time Fourier Analysis......Page 307
 7.4 Spectrographic Displays......Page 327
 7.5 Overlap Addition Method of Synthesis......Page 334
 7.6 Filter Bank Summation Method of Synthesis......Page 346
 7.7 Time-Decimated Filter Banks......Page 355
 7.8 Two-Channel Filter Banks......Page 363
 7.9 Implementation of the FBS Method Using the FFT......Page 373
 7.10 OLA Revisited......Page 380
 7.11 Modifications of the STFT......Page 382
 7.12 Summary......Page 394
 Problems......Page 395
 8.1 Introduction......Page 414
 8.2 Homomorphic Systems for Convolution......Page 416
 8.3 Homomorphic Analysis of the Speech Model......Page 432
 8.4 Computing the Short-Time Cepstrum and Complex Cepstrum of Speech......Page 444
 8.5 Homomorphic Filtering of Natural Speech......Page 455
 8.6 Cepstrum Analysis of All-Pole Models......Page 471
 8.7 Cepstrum Distance Measures......Page 474
 Problems......Page 481
 9.1 Introduction......Page 488
 9.2 Basic Principles of Linear Predictive Analysis......Page 489
 9.3 Computation of the Gain for the Model......Page 501
 9.4 Frequency Domain Interpretations of Linear Predictive Analysis......Page 505
 9.5 Solution of the LPC Equations......Page 520
 9.6 The Prediction Error Signal......Page 542
 9.7 Some Properties of the LPC Polynomial A(z)......Page 553
 9.8 Relation of Linear Predictive Analysis to Lossless Tube Models......Page 561
 9.9 Alternative Representations of the LP Parameters......Page 566
 Problems......Page 575
 10.1 Introduction......Page 593
 10.2 Median Smoothing and Speech Processing......Page 595
 10.3 Speech-Background/Silence Discrimination......Page 601
 10.4 A Bayesian Approach to Voiced/Unvoiced/Silence Detection......Page 610
 10.5 Pitch Period Estimation (Pitch Detection)......Page 618
 10.6 Formant Estimation......Page 650
 Problems......Page 660
 11.1 Introduction......Page 678
 11.2 Sampling Speech Signals......Page 682
 11.3 A Statistical Model for Speech......Page 684
 11.4 Instantaneous Quantization......Page 691
 11.5 Adaptive Quantization......Page 721
 11.6 Quantizing of Speech Model Parameters......Page 733
 11.7 General Theory of Differential Quantization......Page 747
 11.8 Delta Modulation......Page 758
 11.9 Differential PCM (DPCM)......Page 774
 11.10 Enhancements for ADPCM Coders......Page 783
 11.11 Analysis-by-Synthesis Speech Coders......Page 798
 11.12 Open-Loop Speech Coders......Page 821
 11.13 Applications of Speech Coders......Page 829
 11.14 Summary......Page 834
 Problems......Page 835
 12.1 Introduction......Page 857
 12.2 Historical Perspective......Page 859
 12.3 Subband Coding......Page 865
 12.4 Adaptive Transform Coding......Page 876
 12.5 A Perception Model for Audio Coding......Page 881
 12.6 MPEG-1 Audio Coding Standard......Page 896
 12.8 Summary......Page 909
 Problems......Page 910
 13.1 Introduction......Page 922
 13.2 Text Analysis......Page 923
 13.3 Evolution of Speech Synthesis Methods......Page 929
 13.4 Early Speech Synthesis Approaches......Page 931
 13.5 Unit Selection Methods......Page 941
 13.6 TTS Future Needs......Page 957
 13.7 Visual TTS......Page 958
 Problems......Page 962
 14.1 Introduction......Page 965
 14.2 Basic ASR Formulation......Page 967
 14.3 Overall Speech Recognition Process......Page 968
 14.4 Building a Speech Recognition System......Page 969
 14.5 The Decision Processes in ASR......Page 972
 14.6 Step 3: The Search Problem......Page 986
 14.7 Simple ASR System: Isolated Digit Recognition......Page 987
 14.8 Performance Evaluation of Speech Recognizers......Page 989
 14.9 Spoken Language Understanding......Page 992
 14.10 Dialog Management and Spoken Language Generation......Page 995
 14.11 User Interfaces......Page 998
 14.13 Summary......Page 999
 Problems......Page 1000
 A: Speech and Audio Processing Demonstrations......Page 1008
 B: Solution of Frequency-Domain Differential Equations......Page 1020
Bibliography......Page 1023
 A......Page 1046
 C......Page 1047
 E......Page 1048
 H......Page 1049
 L......Page 1050
 M......Page 1051
 P......Page 1052
 S......Page 1053
 V......Page 1056
 Z......Page 1057