Voice Compression and Communications Principles and Applications for Fixed and Wireless Channels

, by Hanzo, Lajos; Somerville, F. Clare A.; Woodward, Jason P.

Note: Supplemental materials are not guaranteed with Rental or Used book purchases.

ISBN: 9780471150398 | 0471150398
Cover: Hardcover
Copyright: 9/11/2001

Rent

(Recommended)

$212.87

Term

Due

Price

Semester

Dec 12

$224.08

Quarter

Aug 13

$212.87

Short Term

Jul 7

$201.67

*This item is part of an exclusive publisher rental program and requires an additional convenience fee. This fee will be reflected in the shopping cart.
Buy New

Currently Available, Usually Ships in 24-48 Hours

$286.88

Up-to-date, expert coverage of topics in wireless voice communications Voice communication is the most important facet of mobile radio service. Even when the predicted surge of wireless data and Internet services becomes a reality, voice will remain the most natural means of human communication. Voice Compression and Communications details issues in wireless voice communications and treats compression, channel coding, and wireless transmission as a joint subject. Part I covers background material, whereas Part II provides detailed information on both proprietary and standardized analysis-by-synthesis codecs, including the speech codecs of virtually all existing wireline-based and wireless systems. Parts III and IV discuss mainly research-based wideband, audio, as well as very low-rate schemes likely to find their way into future standards. Voice Compression and Communications describes fundamental concepts in a non-mathematical way early in the book for those with only a background knowledge of signal processing and communications. More advanced readers will find detailed discussions of theoretical principles, future concepts, and solutions to various specific wireless voice communications problems.

Preface

xxiii

Acknowledgments

xxix

Part I Speech Signals and Waveform Coding

(62)

Speech Signals and Introduction to Speech Coding

(24)

Motivation of Speech Compression

(1)

Basic Characterization of Speech Signals

(3)

Classification of Speech Codecs

(4)

Waveform Coding

(1)

Time-Domain Waveform Coding

(1)

Frequency-Domain Waveform Coding

(1)

Vocoders

(1)

Hybrid Coding

(1)

Waveform Coding

(15)

Digitization of Speech

(1)

Quantization Characteristics

(1)

Quantization Noise and Rate-Distortion Theory

(2)

Nonuniform Quantization for a Known PDF: Companding

(2)

PDF-Independent Quantization Using Logarithmic Compression

(2)

The μ-Law Compander

(1)

The A-Law Compander

(1)

Optimum Nonuniform Quantization

(5)

Chapter Summary

(1)

Predicative Coding

(36)

Forward Predictive Coding

(1)

DPCM Codec Schematic

(1)

Predictor Design

(7)

Problem Formulation

(2)

Covariance Coefficient Computation

(1)

Predictor Coefficient Computation

(4)

Adaptive One-Word-Memory Quantization

(1)

DPCM Performance

(2)

Backward-Adaptive Prediction

(4)

Background

(2)

Stochastic Model Processes

(2)

The 32 kbps G.721 ADPCM Codec

(6)

Functional Description of the G.721 Codec

(1)

Adaptive Quantizer

(1)

G.721 Quantizer Scale Factor Adaptation

(1)

G.721 Adaptation Speed Control

(1)

G.721 Adaptive Prediction and Signal Reconstruction

(2)

Subjective and Objective Speech Quality

(1)

Variable-Rate G.726 and Embeded G.727 ADPCM

(8)

Motivation

(1)

Embedded G.727 ADPCM Coding

(2)

Performance of the Embedded G.727 ADPCM Codec

(6)

Rate-Distortion in Predictive Coding

(4)

Chapter Summary

(1)

Part II Analysis by Synthesis Coding

(276)

Analysis-by-Synthesis Principles

(25)

Motivation

(1)

Analysis-by-Synthesis Codec Structure

(1)

The Short-Term Synthesis Filter

(3)

Long-Term Prediction

(8)

Open-Loop Optimization of LTP Parameters

(5)

Closed-Loop Optimization of LTP Parameters

(3)

Excitation Models

(3)

Adaptive Short-Term and Long-Term Post-Filtering

(2)

Lattice-Based Linear Prediction

(6)

Chapter Summary

(1)

Speech Spectral Quantization

(37)

Log-Area Ratios

(5)

Line Spectral Frequencies

(10)

Derivation of the Line Spectral Frequencies

(4)

Computation of the Line Spectral Frequencies

(1)

Chebyshev-Description of Line Spectral Frequencies

100

(5)

Vector Quantization of Spectral Parameters

105

(8)

Background

105

(1)

Speaker-Adaptive Vector Quantization of LSFs

105

(2)

Stochastic VQ of LPC Parameters

107

(1)

Background

107

(2)

The Stochastic VQ Algorithm

109

(2)

Robust Vector Quantization Schemes for LSFs

111

(1)

LSF Vector-Quantizers in Standard Codecs

112

(1)

Spectral Quantizers for Wideband Speech Coding

113

(13)

Introduction to Wideband Spectral Quantization

113

(2)

Statistical Properties of Wideband LSFs

115

(1)

Speech Codec Specifications

116

(1)

Wideband LSF Vector Quantizers

117

(1)

Memoryless Vector Quantization

117

(3)

Predictive Vector Quantization

120

(2)

Multimode Vector Quantization

122

(3)

Simulation Results and Subjective Evaluations

125

(1)

Conclusions on Wideband Spectral Quantization

126

(1)

Chapter Summary

126

(1)

Regular Pulse Excited Coding

127

(18)

Theoretical Background

127

(6)

The 13 kbps RPE-LTP GSM Speech Encoder

133

(4)

Pre-Processing

133

(2)

STP Analysis Filtering

135

(1)

LTP Analysis Filtering

136

(1)

Regular Excitation Pulse Computation

136

(1)

The 13 kbps RPE-LTP GSM Speech Decoder

137

(3)

Bit Sensitivity of the 13 kbps GSM RPE-LTP Codec

140

(2)

Application Example: A Toolbox-Based Speech Transceiver

142

(2)

Chapter Summary

144

(1)

Forward-Adaptive Code Excited Linear Prediction

145

(62)

Background

145

(1)

The Original CELP Approach

146

(3)

Fixed Codebook Search

149

(2)

CELP Excitation Models

151

(9)

Binary-Pulse Excitation

151

(1)

Transformed Binary Pulse Excitation

151

(1)

Excitation Generation

151

(2)

Bit Sensitivity Analysis of the 48 kbps TBPE Speech Codec

153

(2)

Dual-Rate Algebraic CELP Coding

155

(1)

ACELP Codebook Structure

155

(3)

Dual-Rate ACELP Bit Allocation

158

(1)

Dual-Rate ACELP Codec Performance

158

(2)

Optimization of the CELP Codec Parameters

160

(15)

Introduction

160

(1)

Calculation of the Excitation Parameters

160

(1)

Full Codebook Search Theory

160

(2)

Sequential Search Procedure

162

(1)

Full Search Procedure

163

(1)

Suboptimal Search Procedures

164

(1)

Quantization of the Codebook Gains

165

(2)

Calculation of the Synthesis Filter Parameters

167

(1)

Bandwidth Expansion

168

(1)

Least Squares Techniques

168

(3)

Optimization via Powell's Method

171

(1)

Simulated Annealing and the Effects of Quantization

171

(4)

The Error-Sensitivity of CELP Codecs

175

(12)

Introduction

175

(1)

Improving the Spectral Information Error Sensitivity

176

(1)

LSF Ordering Policies

176

(2)

The Effect of FEC on the Spectral Parameters

178

(1)

The Effect of Interpolation

179

(1)

Improving the Error Sensitivity of the Excitation Parameters

180

(1)

The Fixed Codebook Index

180

(1)

The Fixed Codebook Gain

180

(1)

Adaptive Codebook Delay

181

(1)

Adaptive Codebook Gain

182

(1)

Matching Channel Codecs to the Speech Codec

182

(4)

Error-Resilience Conclusions

186

(1)

Application Example: A Dual-Mode 3.1 kBd Speech Transceiver

187

(13)

The Transceiver Scheme

187

(1)

Reconfigurable Modulation

188

(2)

Source-Matched Error Protection

190

(1)

Low-Quality 3.1 kBd Mode

190

(2)

High-Quality 3.1 kBd Mode

192

(3)

Voice Activity Detection and Packet Reservation Multiple Access

195

(1)

kBd System Performance

196

(3)

kBd System Summary

199

(1)

Multi-Slot PRMA Transceiver

200

(6)

Background and Motivation

200

(1)

PRMA-Assisted Multi-Slot Adaptive Modulation

201

(1)

Adaptive GSM-Like Schemes

202

(2)

Adaptive DECT-Like Schemes

204

(1)

Summary of Adaptive Multi-Slot PRMA

205

(1)

Chapter Summary

206

(1)

Standard Forword-Adaptive CELP Codecs

207

(72)

Background

207

(1)

The U.S. DoD FS-1016 4.8 kbits/s CELP Codec

207

(6)

Introduction

207

(2)

LPC Analysis and Quantization

209

(1)

The Adaptive Codebook

210

(1)

The Fixed Codebook

210

(2)

Error Concealment Techniques

212

(1)

Decoder Post-Filtering

212

(1)

Conclusion

212

(1)

The IS-54 DAMPS kbps Pan American Speech Codec

213

(3)

The 6.7 kbps Japanese Digital Cellular System's Speech Codec

216

(2)

The Qualcomm Variable-Rate CELP Codec

218

(7)

Introduction

218

(1)

Codec Schematic and Bit Allocation

219

(1)

Codec Rate Selection

219

(1)

LPC Analysis and Quantization

220

(2)

The Pitch Filter

222

(1)

The Fixed Codebook

223

(1)

Rate 1/8 Filter Excitation

223

(1)

Decoder Post-Filtering

224

(1)

Error Protection and Concealment Techniques

224

(1)

Conclusion

225

(1)

Japanese Half-Rate Speech Codec

225

(8)

Introduction

225

(1)

Codec Schematic and Bit Allocation

226

(2)

Encoder Pre-Processing

228

(1)

LPC Analysis and Quantization

228

(1)

The Weighting Filter

229

(1)

Excitation Vector 1

229

(2)

Excitation Vector 2

231

(1)

Channel Coding

231

(1)

Decoder Post-Processing

232

(1)

The Half-Rate GSM Codec

233

(4)

Half-Rate GSM Codec Outline and Bit Allocation

233

(2)

Spectral Quantization in the Half-Rate GSM Codec

235

(1)

Error Protection

236

(1)

The 8 kbits/s G.729 Codec

237

(19)

Introduction

237

(1)

Codec Schematic and Bit Allocation

237

(1)

Encoder Pre-Processing

238

(1)

LPC Analysis and Quantization

239

(2)

The Weighting Filter

241

(1)

The Adaptive Codebook

242

(1)

The Fixed Algebraic Codebook

242

(3)

Quantization of the Gains

245

(1)

Decoder Post-Processing

246

(2)

G.729 Error Concealment Techniques

248

(1)

G.729 Bit Sensitivity

249

(1)

Orthogonal Frequency Division Multiplex Transmission of G.729 Encoded Speech

250

(1)

Background

250

(1)

System Overview

251

(1)

Turbo Channel Encoding

251

(1)

OFDM in the FRAMES Speech/Data Sub-Burst

252

(1)

Channel Model

253

(1)

Turbo-Coded G.729 OFDM Parameters

253

(1)

Turbo-Coded G.729 OFDM Performance

254

(1)

Turbo-Coded G.729 OFDM Summary

255

(1)

G.729 Summary

256

(1)

The Reduced Complexity G.729 Annex A Codec

256

(3)

Introduction

256

(1)

The Perceptual Weighting Filter

257

(1)

The Open-Loop Pitch Search

257

(1)

The Closed-Loop Pitch Search

257

(1)

The Algebraic Codebook Search

258

(1)

The Decoder Post-Processing

258

(1)

Conclusions

259

(1)

The 12.2 kbps Enhanced Full-Rate GSM Speech Codec

259

(5)

Codec Outline

259

(2)

Enhanced Full-Rate EFR-GSM Encoder

261

(1)

Spectral Quantization in the Enhanced Full-Rate GSM Codec

261

(2)

Adaptive Codebook Search

263

(1)

Fixed Codebook Search

263

(1)

The Enhanced Full-Rate 7.4 kbps IS-136 Speech Codec

264

(4)

IS-136 Codec Outline

264

(1)

IS-136 Bit-Allocation Scheme

265

(2)

Fixed Codebook Search

267

(1)

IS-136 Channel Coding

267

(1)

The ITU G.723.1 Dual-Rate Codec

268

(9)

Introduction

268

(1)

G.723.1 Encoding Principle

269

(1)

Vector-Quantization of the LSPs

270

(1)

Formant-based Weighting Filter

271

(1)

The 6.3 kbps High-Rate G.723.1 Excitation

272

(1)

The 5.3 kbps Low-Rate G.723.1 Excitation

273

(1)

G.723.1 Bit-Allocation

274

(2)

G.723.1 Error Sensitivity

276

(1)

Chapter Summary

277

(2)

Backward-Adaptive Code Excited Linear Prediction

279

(60)

Introduction

279

(1)

Motivation and Background

279

(3)

Backward-Adaptive G.728 Codec Schematic

282

(2)

Backward-Adaptive G.728 Coding Algorithm

284

(14)

G.728 Error Weighting

284

(1)

G.728 Windowing

284

(4)

Codebook Gain Adaption

288

(2)

G.728 Codebook Search

290

(2)

G.728 Excitation Vector Quantization

292

(2)

G.728 Adaptive Post-Filtering

294

(1)

Adaptive Long-Term Post-Filtering

294

(3)

G.728 Adaptive Short-Term Post-Filtering

297

(1)

Complexity and Performance of the G.728 Codec

297

(1)

Reduced-Rate G.728-Like Codec: Variable-Length Excitation Vector

298

(2)

The Effects of Long-Term Prediction

300

(5)

Closed-Loop Codebook Training

305

(4)

Reduced-Rate G.728-Like Codec II: Constant-Length Excitation Vector

309

(1)

Programmable-Rate 8-4 kbps Low-Delay CELP Codec

310

(17)

Motivation

310

(1)

8-4 kbps Codec Improvements Due to Increasing Codebook Sizes

311

(1)

8-4 kbps Codecs-Forward Adaption of the Short-Term Synthesis Filter

311

(2)

Forward Adaption of the Long-Term Predictor

313

(1)

Initial Experiments

313

(3)

Quantization of Jointly Optimized Gains

316

(4)

8-4 kbps Codecs-Voiced/Unvoiced Codebooks

320

(1)

Low-Delay Codecs at 4-8 kbits/s

321

(3)

Low-Delay ACELP Codec

324

(3)

Backward-Adaptive Error Sensitivity Issues

327

(6)

The Error Sensitivity of the G.728 Codec

327

(1)

The Error Sensitivity of Our 4-8 kbits/s Low-Delay Codecs

328

(4)

The Error Sensitivity of Our Low-Delay ACELP Codec

332

(1)

A Low-Delay Multimode Speech Transceiver

333

(5)

Background

333

(1)

8-16 kbps Codec Performance

334

(1)

Transmission Issues

335

(1)

Higher-Quality Mode

335

(2)

Lower-Quality Mode

337

(1)

Speech Transceiver Performance

337

(1)

Chapter Summary

338

(1)

Part III Wideband Coding and Transmission

339

(46)

Wideband Speech Coding

341

(44)

Sub-band-ADPCM Wideband Coding at 64 kbps

341

(16)

Introduction and Specifications

341

(1)

G.722 Codec Outline

342

(4)

Principles of Sub-Band Coding

346

(1)

Quandrature Mirror Filtering

346

(1)

Analysis Filtering

346

(2)

Synthesis Filtering

348

(2)

Practical QMF Design Constraints

350

(5)

G.722 Adaptive Quantization and Prediction

355

(2)

G.722 Coding Performance

357

(1)

Wideband Transform Coding at 32 kbps

357

(3)

Background

357

(1)

Transform-Coding Algorithm

357

(3)

Sub-Band-Split Wideband CELP Codecs

360

(3)

Background

360

(1)

Sub-Band-Based Wideband CELP Coding

360

(1)

Motivation

360

(2)

Low-Band Coding

362

(1)

High-Band Coding

362

(1)

Bit-Allocation Scheme

362

(1)

Fullband Wideband ACELP Coding

363

(5)

Wideband ACELP Excitation

363

(3)

Backward-Adaptive 32 kbps Wideband ACELP

366

(1)

Forward-Adaptive 9.6 kbps Wideband ACELP

366

(2)

A Turbo-Coded Burst-by-Burst Adaptive Wideband Speech Transceiver

368

(16)

Background and Motivation

368

(2)

System Overview

370

(1)

System Parameters

371

(1)

Constant Throughput Adaptive Modulation

372

(1)

Adaptive Wideband Transceiver Performance

373

(1)

Multimode Transceiver Adaptation

374

(1)

Transceiver Mode Switching

375

(3)

The Wideband G.722.1 Codec

378

(1)

Audio Codec Overview

378

(1)

Detailed Description of the Audio Codec

379

(2)

Wideband Adaptive System Performance

381

(1)

Audio Frame Error Results

381

(1)

Audio Segmental SNR Performance and Discussions

382

(2)

G.722.1 Audio Transceiver Summary and Conclusions

384

(1)

Chapter Summary

384

(1)

Part IV Very Low-Rate Coding and Transmission

385

(204)

Overview of Low-Rate Speech Coding

387

(24)

Low-Bitrate Speech Coding

387

(13)

Analysis-by-Synthesis Coding

389

(2)

Speech Coding at 2.4 kbps

391

(1)

Background to 2.4 kbps Speech Coding

392

(1)

Frequency Selective Harmonic Coder

393

(1)

Sinusoidal Transform Coder

394

(1)

Multiband Excitation Coders

395

(1)

Sub-Band Linear Prediction Coder

396

(1)

Mixed Excitation Linear Prediction Coder

396

(1)

Waveform Interpolation Coder

397

(1)

Speech Coding Below 2.4 kbps

398

(2)

Linear Predictive Coding Model

400

(3)

Short-Term Prediction

400

(2)

Long-Term Prediction

402

(1)

Final Analysis-by-Synthesis Model

402

(1)

Speech Quality Measurements

403

(3)

Objective Speech Quality Measures

404

(1)

Subjective Speech Quality Measures

404

(1)

2.4 kbps Selection Process

405

(1)

Speech Database

406

(3)

Chapter Summary

409

(2)

Linear Predictive Vocoder

411

(30)

Overview of a Linear Predictive Vocoder

411

(1)

Line Spectrum Frequencies Quantization

412

(5)

Line Spectrum Frequencies Scalar Quantization

412

(2)

Line Spectrum Frequencies Vector Quantization

414

(3)

Pitch Detection

417

(11)

Voiced-Unvoiced Decision

418

(3)

Oversampled Pitch Detector

421

(1)

Pitch Tracking

422

(3)

Computational Complexity

425

(1)

Integer Pitch Detector

426

(2)

Unvoiced Frames

428

(1)

Voiced Frames

429

(1)

Placement of Excitation Pulses

429

(1)

Pulse Energy

429

(1)

Adaptive Post-Filter

430

(2)

Pulse Dispersion Filter

432

(5)

Pulse Dispersion Principles

432

(2)

Pitch-Independent Glottal Pulse Shaping Filter

434

(1)

Pitch-Dependent Glottal Pulse Shaping Filter

435

(2)

Results for Linear Predictive Vocoder

437

(3)

Chapter Summary

440

(1)

Wavelets and Pitch Detection

441

(20)

Conceptual Introduction to Wavelets

441

(3)

Fourier Theory

441

(1)

Wavelet Theory

442

(1)

Detecting Discontinuities with Wavelets

443

(1)

Introduction to Wavelet Mathematics

444

(5)

Multiresolution Analysis

445

(1)

Polynomial Spline Wavelets

446

(1)

Pyramidal Algorithm

447

(1)

Boundary Effects

448

(1)

Pre-Processing the Wavelet Transform Signal

449

(3)

Spurious Pulses

449

(2)

Normalization

451

(1)

Candidate Glottal Pulses

452

(1)

Voiced-Unvoiced Decision

452

(1)

Wavelet-Based Pitch Detector

453

(7)

Dynamic Programming

454

(3)

Autocorrelation Simplification

457

(3)

Summary and Conclusions

460

(1)

Zinc Function Excitation

461

(40)

Introduction

461

(1)

Overview of Prototype Waveform Interpolation Zinc Function Excitation

462

(4)

Coding Scenarios

462

(1)

U-U-U Encoder Scenario

463

(1)

U-U-V Encoder Scenario

463

(1)

V-U-U Encoder Scenario

464

(1)

U-V-U Encoder Scenario

464

(1)

V-V-V Encoder Scenario

465

(1)

V-U-V Encoder Scenario

465

(1)

U-V-V Encoder Scenario

465

(1)

V-V-U Encoder Scenario

465

(1)

U-V Decoder Scenario

465

(1)

U-U Decoder Scenario

465

(1)

V-U Decoder Scenario

466

(1)

V-V Decoder Scenario

466

(1)

Zinc Function Modeling

466

(4)

Error Minimization

467

(1)

Computational Complexity

468

(1)

Reducing the Complexity of Zinc Function Excitation Optimization

469

(1)

Phases of the Zinc Functions

470

(1)

Pitch Detection

470

(3)

Voiced-Unvoiced Boundaries

471

(1)

Pitch Prototype Selection

471

(2)

Voiced Speech

473

(4)

Energy Scaling

475

(1)

Quantization

476

(1)

Excitation Interpolation Between Prototype Segments

477

(6)

ZFE Interpolation Regions

477

(3)

ZFE Amplitude Parameter Interpolation

480

(1)

ZFE Position Parameter Interpolation

480

(1)

Implicit Signaling of Prototype Zero Crossing

481

(1)

Removal of ZFE Pulse Position Signaling and Interpolation

482

(1)

Pitch Synchronous Interpolation of Line Spectrum Frequencies

482

(1)

ZFE Interpolation Example

482

(1)

Unvoiced Speech

483

(1)

Adaptive Post-Filter

483

(1)

Results for Single Zinc Function Excitation

483

(3)

Error Sensitivity of the 1.9 kbps PWI-ZFE Coder

486

(4)

Parameter Sensitivity of the 1.9 kbps PWI-ZFE coder

486

(1)

Line Spectrum Frequencies

487

(1)

Voiced-Unvoiced Flag

487

(1)

Pitch Period

487

(1)

Excitation Amplitude Parameters

487

(1)

Root Mean Square Energy Parameter

487

(1)

Boundary Shift Parameter

488

(1)

Degradation from Bit Corruption

488

(1)

Error Sensitivity Classes

489

(1)

Multiple Zinc Function Excitation

490

(6)

Encoding Algorithm

490

(2)

Performance of Multiple Zinc Function Excitation

492

(4)

A Sixth-Rate, 3.8 kbps GSM-Like Speech Transceiver

496

(4)

Motivation

496

(1)

The Turbo-Coded Sixth-Rate 3.8 kbps GSM-Like System

496

(1)

Turbo Channel Coding

497

(1)

The Turbo-Coded GMSK Transceiver

498

(2)

System Performance Results

500

(1)

Chapter Summary

500

(1)

Mixed-Multiband Excitation

501

(30)

Introduction

501

(1)

Overview of Mixed-Multiband Excitation

502

(2)

Finite Impulse Response Filter

504

(3)

Mixed-Multiband Excitation Encoder

507

(3)

Voicing Strengths

507

(3)

Mixed-Multiband Excitation Decoder

510

(3)

Adaptive Post-Filter

511

(2)

Computational Complexity

513

(1)

Performance of the Mixed-Multiband Excitation Coder

513

(7)

Performance of a Mixed-Multiband Excitation Linear Predictive Coder

514

(3)

Performance of a Mixed-Multiband Excitation and Zinc Function Prototype Excitation Coder

517

(3)

A Higher Rate 3.85 kbps Mixed-Multiband Excitation Scheme

520

(3)

A 2.35 kbit/s Joint-Detection-Based CDMA Speech Transceiver

523

(7)

Background

523

(1)

The Speech Codec's Bit Allocation

524

(1)

The Speech Codec's Error Sensitivity

525

(1)

Channel Coding

526

(1)

The JD-CDMA Speech System

527

(1)

System Performance

528

(1)

Conclusions on the JD-CDMA Speech Transceiver

529

(1)

Chapter Summary

530

(1)

Sinusoidal Transform Coding Below 4 kbps

531

(34)

Introduction

531

(1)

Sinusoidal Analysis of Speech Signals

532

(2)

Sinusoidal Analysis with Peak-Picking

532

(2)

Sinusoidal Analysis Using Analysis-by-Synthesis

534

(1)

Sinusoidal Synthesis of Speech Signals

534

(2)

Frequency, Amplitude, and Phase Interpolation

534

(1)

Overlap-Add Interpolation

535

(1)

Low-Bitrate Sinusoidal Coders

536

(3)

Increased Frame Length

538

(1)

Incorporating Linear Prediction Analysis

538

(1)

Incorporating Prototype Waveform Interpolation

539

(2)

Encoding the Sinusoidal Frequency Component

541

(2)

Determining the Excitation Components

543

(5)

Peak-Picking of the Residual Spectra

543

(1)

Analysis-by-Synthesis of the Residual Spectrum

543

(2)

Computational Complexity

545

(1)

Reducing the Computational Complexity

545

(3)

Quantizing the Excitation Parameters

548

(8)

Encoding the Sinusoidal Amplitudes

548

(1)

Vector Quantization of the Amplitudes

548

(1)

Interpolation and Decimation

549

(1)

Vector Quantization

550

(1)

Vector Quantization Performance

551

(1)

Scalar Quantization of the Amplitudes

552

(1)

Encoding the Sinusoidal Phases

553

(1)

Vector Quantization of the Phases

553

(1)

Encoding the Phases with a Voiced-Unvoiced Switch

554

(1)

Encoding the Sinusoidal Fourier Coefficients

554

(1)

Equivalent Rectangular Bandwidth Scale

555

(1)

Voiced-Unvoiced Flag

556

(1)

Sinusoidal Transform Decoder

556

(2)

Pitch Synchronous Interpolation

557

(1)

Fourier Coefficient Interpolation

557

(1)

Frequency Interpolation

557

(1)

Computational Complexity

557

(1)

Speech Coder Performance

558

(5)

Chapter Summary

563

(2)

Conclusions on Low-Rate Coding

565

(4)

Overview

565

(1)

Listening Tests

565

(2)

Summary of Very Low-Rate Coding

567

(1)

Further Research

568

(1)

Comparison of Speech Codecs and Transceivers

569

(20)

Background to Speech Quality Evaluation

569

(1)

Objective Speech Quality Measures

570

(7)

Introduction

570

(1)

Signal-to-Noise Ratios

571

(1)

Articulation Index

571

(1)

Cepstral Distance

572

(2)

Example: Computation of Cepstral Coefficients

574

(2)

Logarithmic Likelihood Ratio

576

(1)

Euclidean Distance

577

(1)

Subjective Measures

577

(1)

Quality Tests

577

(1)

Comparison of Subjective and Objective Measures

578

(2)

Background

578

(2)

Intelligibility Tests

580

(1)

Subjective Speech Quality of Various Codecs

580

(2)

Error Sensitivity Comparison of Various Codecs

582

(1)

Objective Speech Performance of Various Transceivers

583

(6)

Appendix A Constructing the Quadratic Spline Wavelets

589

(4)

Appendix B Zinc Function Excitation

593

(4)

Appendix C Probability Density Function for Amplitudes

597

(4)

Bibliography

601

(22)

Index

623

(8)

Author Index

631

Please wait while the item is added to your bag...

FREE SHIPPING

Rent More, Save More! Use code: BBRENTAL

5% off 1 book, 7% off 2 books, 10% off 3+ books

Voice Compression and Communications Principles and Applications for Fixed and Wireless Channels

Summary

Author Biography

Table of Contents

Supplemental Materials

FREE SHIPPING

Rent More, Save More! Use code: BBRENTAL

5% off 1 book, 7% off 2 books, 10% off 3+ books

Voice Compression and Communications Principles and Applications for Fixed and Wireless Channels

Summary

Author Biography

Table of Contents

Supplemental Materials

Digital License