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标题:
Audio Signal Processing and Coding
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hasky
时间:
2016-11-12 14:46
标题:
Audio Signal Processing and Coding
语音信号处理及压缩编码算法介绍
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1 INTRODUCTION 1
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1.1 Historical Perspective 1
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1.2 A General Perceptual Audio Coding Architecture 4
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1.3 Audio Coder Attributes 5
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1.3.1 Audio Quality 6
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1.3.2 Bit Rates 6
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1.3.3 Complexity 6
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1.3.4 Codec Delay 7
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1.3.5 Error Robustness 7
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1.4 Types of Audio Coders – An Overview 7
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1.5 Organization of the Book 8
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1.6 Notational Conventions 9
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2 SIGNAL PROCESSING ESSENTIALS 13
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2.1 Introduction 13
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2.2 Spectra of Analog Signals 13
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2.3 Review of Convolution and Filtering 16
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2.4 Uniform Sampling 17
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2.5 Discrete-Time Signal Processing 20
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2.5.1 Transforms for Discrete-Time Signals 20
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2.5.2 The Discrete and the Fast Fourier Transform 22
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2.5.3 The Discrete Cosine Transform 23
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2.5.4 The Short-Time Fourier Transform 23
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2.6 Difference Equations and Digital Filters 25
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2.7 The Transfer and the Frequency Response Functions 27
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2.7.1 Poles, Zeros, and Frequency Response 29
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2.7.2 Examples of Digital Filters for Audio Applications 30
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2.8 Review of Multirate Signal Processing 33
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2.8.1 Down-sampling by an Integer 33
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2.8.2 Up-sampling by an Integer 35
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2.8.3 Sampling Rate Changes by Noninteger Factors 36
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2.8.4 Quadrature Mirror Filter Banks 36
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2.9 Discrete-Time Random Signals 39
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2.9.1 Random Signals Processed by LTI Digital Filters 42
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2.9.2 Autocorrelation Estimation from Finite-Length Data 44
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2.10 Summary 44
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3 QUANTIZATION AND ENTROPY CODING 51
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3.1 Introduction 51
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3.1.1 The Quantization–Bit Allocation–Entropy Coding Module 52
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3.2 Density Functions and Quantization 53
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3.3 Scalar Quantization 54
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3.3.1 Uniform Quantization 54
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3.3.2 Nonuniform Quantization 57
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3.3.3 Differential PCM 59
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3.4 Vector Quantization 62
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3.4.1 Structured VQ 64
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3.4.2 Split-VQ 67
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3.4.3 Conjugate-Structure VQ 69
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3.5 Bit-Allocation Algorithms 70
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3.6 Entropy Coding 74
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3.6.1 Huffman Coding 77
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3.6.2 Rice Coding 81
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3.6.3 Golomb Coding 82
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3.6.4 Arithmetic Coding 83
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3.7 Summary 85
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4 LINEAR PREDICTION IN NARROWBAND AND WIDEBAND
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CODING 91
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4.1 Introduction 91
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4.2 LP-Based Source-System Modeling for Speech 92
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4.3 Short-Term Linear Prediction 94
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4.3.1 Long-Term Prediction 95
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4.3.2 ADPCM Using Linear Prediction 96
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4.4 Open-Loop Analysis-Synthesis Linear Prediction 96
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4.5 Analysis-by-Synthesis Linear Prediction 97
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4.5.1 Code-Excited Linear Prediction Algorithms 100
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4.6 Linear Prediction in Wideband Coding 102
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4.6.1 Wideband Speech Coding 102
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4.6.2 Wideband Audio Coding 104
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4.7 Summary 106
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5 PSYCHOACOUSTIC PRINCIPLES 113
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5.1 Introduction 113
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5.2 Absolute Threshold of Hearing 114
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5.3 Critical Bands 115
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5.4 Simultaneous Masking, Masking Asymmetry, and the Spread of Masking 120
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5.4.1 Noise-Masking-Tone 123
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5.4.2 Tone-Masking-Noise 124
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5.4.3 Noise-Masking-Noise 124
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5.4.4 Asymmetry of Masking 124
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5.4.5 The Spread of Masking 125
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5.5 Nonsimultaneous Masking 127
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5.6 Perceptual Entropy 128
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5.7 Example Codec Perceptual Model: ISO/IEC 11172-3(MPEG - 1) Psychoacoustic Model 1 130
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5.7.1 Step 1: Spectral Analysis and SPL Normalization 131
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5.7.2 Step 2: Identification of Tonal and Noise Maskers 131
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5.7.3 Step 3: Decimation and Reorganization of Maskers 135
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5.7.4 Step 4: Calculation of Individual Masking Thresholds 136
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5.7.5 Step 5: Calculation of Global Masking Thresholds 138
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5.8 Perceptual Bit Allocation 138
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5.9 Summary 140
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6 TIME-FREQUENCY ANALYSIS: FILTER BANKS AND
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TRANSFORMS 145
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6.1 Introduction 145
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6.2 Analysis-Synthesis Framework for M-band Filter Banks 146
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6.3 Filter Banks for Audio Coding: Design Considerations 148
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6.3.1 The Role of Time-Frequency Resolution in Masking
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Power Estimation 149
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6.3.2 The Role of Frequency Resolution in Perceptual Bit
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Allocation 149
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6.3.3 The Role of Time Resolution in Perceptual Bit
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Allocation 150
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6.4 Quadrature Mirror and Conjugate Quadrature Filters 155
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6.5 Tree-Structured QMF and CQF M-band Banks 156
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6.6 Cosine Modulated “Pseudo QMF” M-band Banks 160
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6.7 Cosine Modulated Perfect Reconstruction (PR) M-band Banks
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and the Modified Discrete Cosine Transform (MDCT) 163
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6.7.1 Forward and Inverse MDCT 165
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6.7.2 MDCT Window Design 165
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6.7.3 Example MDCT Windows (Prototype FIR Filters) 167
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6.8 Discrete Fourier and Discrete Cosine Transform 178
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6.9 Pre-echo Distortion 180
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6.10 Pre-echo Control Strategies 182
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6.10.1 Bit Reservoir 182
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6.10.2 Window Switching 182
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6.10.3 Hybrid, Switched Filter Banks 184
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6.10.4 Gain Modification 185
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6.10.5 Temporal Noise Shaping 185
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6.11 Summary 186
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7 TRANSFORM CODERS 195
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7.1 Introduction 195
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7.2 Optimum Coding in the Frequency Domain 196
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7.3 Perceptual Transform Coder 197
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7.3.1 PXFM 198
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7.3.2 SEPXFM 199
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7.4 Brandenburg-Johnston Hybrid Coder 200
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7.5 CNET Coders 201
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7.5.1 CNET DFT Coder 201
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7.5.2 CNET MDCT Coder 1 201
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7.5.3 CNET MDCT Coder 2 202
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7.6 Adaptive Spectral Entropy Coding 203
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7.7 Differential Perceptual Audio Coder 204
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7.8 DFT Noise Substitution 205
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7.9 DCT with Vector Quantization 206
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7.10 MDCT with Vector Quantization 207
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7.11 Summary 208
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8 SUBBAND CODERS 211
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8.1 Introduction 211
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8.1.1 Subband Algorithms 212
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8.2 DWT and Discrete Wavelet Packet Transform (DWPT) 214
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8.3 Adapted WP Algorithms 218
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8.3.1 DWPT Coder with Globally Adapted Daubechies
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Analysis Wavelet 218
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8.3.2 Scalable DWPT Coder with Adaptive Tree Structure 220
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8.3.3 DWPT Coder with Globally Adapted General
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Analysis Wavelet 223
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8.3.4 DWPT Coder with Adaptive Tree Structure and
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Locally Adapted Analysis Wavelet 223
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8.3.5 DWPT Coder with Perceptually Optimized Synthesis
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Wavelets 224
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8.4 Adapted Nonuniform Filter Banks 226
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8.4.1 Switched Nonuniform Filter Bank Cascade 226
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8.4.2 Frequency-Varying Modulated Lapped Transforms 227
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8.5 Hybrid WP and Adapted WP/Sinusoidal Algorithms 227
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8.5.1 Hybrid Sinusoidal/Classical DWPT Coder 228
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8.5.2 Hybrid Sinusoidal/M-band DWPT Coder 229
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8.5.3 Hybrid Sinusoidal/DWPT Coder with WP Tree
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Structure Adaptation (ARCO) 230
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8.6 Subband Coding with Hybrid Filter Bank/CELP Algorithms 233
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8.6.1 Hybrid Subband/CELP Algorithm for Low-Delay
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Applications 234
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8.6.2 Hybrid Subband/CELP Algorithm for
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Low-Complexity Applications 235
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8.7 Subband Coding with IIR Filter Banks 237
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9 SINUSOIDAL CODERS 241
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9.1 Introduction 241
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9.2 The Sinusoidal Model 242
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9.2.1 Sinusoidal Analysis and Parameter Tracking 242
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9.2.2 Sinusoidal Synthesis and Parameter Interpolation 245
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9.3 Analysis/Synthesis Audio Codec (ASAC) 247
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9.3.1 ASAC Segmentation 248
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9.3.2 ASAC Sinusoidal Analysis-by-Synthesis 248
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9.3.3 ASAC Bit Allocation, Quantization, Encoding, and
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Scalability 248
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9.4 Harmonic and Individual Lines Plus Noise Coder (HILN) 249
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9.4.1 HILN Sinusoidal Analysis-by-Synthesis 250
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9.4.2 HILN Bit Allocation, Quantization, Encoding, and
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Decoding 251
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9.5 FM Synthesis 251
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9.5.1 Principles of FM Synthesis 252
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9.5.2 Perceptual Audio Coding Using an FM Synthesis
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Model 252
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9.6 The Sines + Transients + Noise (STN) Model 254
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9.7 Hybrid Sinusoidal Coders 255
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9.7.1 Hybrid Sinusoidal-MDCT Algorithm 256
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9.7.2 Hybrid Sinusoidal-Vocoder Algorithm 257
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9.8 Summary 258
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10 AUDIO CODING STANDARDS AND ALGORITHMS 263
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10.1 Introduction 263
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10.2 MIDI Versus Digital Audio 264
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10.2.1 MIDI Synthesizer 264
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10.2.2 General MIDI (GM) 266
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10.2.3 MIDI Applications 266
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10.3 Multichannel Surround Sound 267
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10.3.1 The Evolution of Surround Sound 267
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10.3.2 The Mono, the Stereo, and the Surround Sound
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Formats 268
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10.3.3 The ITU-R BS.775 5.1-Channel Configuration 268
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10.4 MPEG Audio Standards 270
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10.4.1 MPEG-1 Audio (ISO/IEC 11172-3) 275
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10.4.2 MPEG-2 BC/LSF (ISO/IEC-13818-3) 279
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10.4.3 MPEG-2 NBC/AAC (ISO/IEC-13818-7) 283
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10.4.4 MPEG-4 Audio (ISO/IEC 14496-3) 289
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10.4.5 MPEG-7 Audio (ISO/IEC 15938-4) 309
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10.4.6 MPEG-21 Framework (ISO/IEC-21000) 317
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10.4.7 MPEG Surround and Spatial Audio Coding 319
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10.5 Adaptive Transform Acoustic Coding (ATRAC) 319
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10.6 Lucent Technologies PAC, EPAC, and MPAC 321
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10.6.1 Perceptual Audio Coder (PAC) 321
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10.6.2 Enhanced PAC (EPAC) 323
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10.6.3 Multichannel PAC (MPAC) 323
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10.7 Dolby Audio Coding Standards 325
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10.7.1 Dolby AC-2, AC-2A 325
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10.7.2 Dolby AC-3/Dolby Digital/Dolby SR · D 327
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10.8 Audio Processing Technology APT-x100 335
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10.9 DTS – Coherent Acoustics 338
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10.9.1 Framing and Subband Analysis 338
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10.9.2 Psychoacoustic Analysis 339
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10.9.3 ADPCM – Differential Subband Coding 339
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10.9.4 Bit Allocation, Quantization, and Multiplexing 341
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10.9.5 DTS-CA Versus Dolby Digital 342
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11 LOSSLESS AUDIO CODING AND DIGITAL WATERMARKING 343
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11.1 Introduction 343
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11.2 Lossless Audio Coding (L2AC) 344
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11.2.1 L2AC Principles 345
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11.2.2 L2AC Algorithms 346
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11.3 DVD-Audio 356
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11.3.1 Meridian Lossless Packing (MLP) 358
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11.4 Super-Audio CD (SACD) 358
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11.4.1 SACD Storage Format 362
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11.4.2 Sigma-Delta Modulators (SDM) 362
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11.4.3 Direct Stream Digital (DSD) Encoding 364
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11.5 Digital Audio Watermarking 368
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11.5.1 Background 370
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11.5.2 A Generic Architecture for DAW 374
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11.5.3 DAW Schemes – Attributes 377
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11.6 Summary of Commercial Applications 378
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12 QUALITY MEASURES FOR PERCEPTUAL AUDIO CODING 383
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12.1 Introduction 383
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12.2 Subjective Quality Measures 384
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12.3 Confounding Factors in Subjective Evaluations 386
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12.4 Subjective Evaluations of Two-Channel Standardized Codecs 387
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12.5 Subjective Evaluations of 5.1-Channel Standardized Codecs 388
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12.6 Subjective Evaluations Using Perceptual Measurement Systems 389
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12.6.1 CIR Perceptual Measurement Schemes 390
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12.6.2 NSE Perceptual Measurement Schemes 390
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12.7 Algorithms for Perceptual Measurement 391
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12.7.1 Example: Perceptual Audio Quality Measure (PAQM) 392
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12.7.2 Example: Noise-to-Mask Ratio (NMR) 396
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12.7.3 Example: Objective Audio Signal Evaluation (OASE) 399
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12.8 ITU-R BS.1387 and ITU-T P.861: Standards for Perceptual
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Quality Measurement 401
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12.9 Research Directions for Perceptual Codec Quality Measures 402
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时间:
2016-11-12 15:14
谢谢分享,必须赞一个～
. V8 G. U7 @8 O5 I3 h: Z! s/ R
作者:
sunygd
时间:
2016-11-14 11:27
谢谢分享
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