DIGITAL AUDIO SIGNAL PROCESSING
1 Introduction 1 11 Studio Technology 1 12 DigitalTransmissionSystems 2 13 StorageMedia 10 14 Audio Components at Home 13 References 17 2 Quantization 21 21 SignalQuantization 21 211 ClassicalQuantizationModel 21 212 QuantizationTheorem 24 213 Statistics ofQuantizationError 30 22 Dither 36 221 Basics 36 222 Implementation 39 223 Examples 39 23 SpectrumShapingofQuantization–NoiseShaping 42 24 NumberRepresentation 47 241 Fixed-pointNumberRepresentation 47 242 Floating-pointNumberRepresentation 53 243 EffectsonFormatConversionandAlgorithms 56 25 JavaApplet–Quantization,Dither,andNoiseShaping 58 26 Exercises 59 References 61 3 AD/DA Conversion 63 31 Methods 63 311 Nyquist Sampling 63 312 Oversampling 65 313 Delta-sigma Modulation 66 32 ADConverters 79 321 Specifications 79 322 ParallelConverter 82 323 SuccessiveApproximation 83 324 Counter Methods 84 325 Delta-sigmaADConverter 85 33 DAConverters 86 331 Specifications 86 332 SwitchedVoltage andCurrentSources 89 333 WeightedResistors andCapacitors 89 334 R-2RResistorNetworks 92 335 Delta-sigmaDAConverter 92 34 JavaApplet–OversamplingandQuantization 92 35 Exercises 94 References 95 4 Audio Processing Systems 97 41 DigitalSignalProcessors 98 411 Fixed-pointDSPs 98 412 Floating-pointDSPs 100 42 Digital Audio Interfaces 101 421 Two-channelAES/EBUInterface 101 422 MADI Interface 102 43 Single-processorSystems 107 431 Peripherals 107 432 Control 107 44 Multi-processor Systems 109 441 ConnectionviaSerialLinks 110 442 ConnectionviaParallelLinks 111 443 ConnectionviaStandardBusSystems 112 444 ScalableAudioSystem 113 References 113 5 Equalizers 115 51 Basics 115 52 Recursive Audio Filters 119 521 Design 119 522 Parametric Filter Structures 128 523 QuantizationEffects 138 53 Nonrecursive Audio Filters 157 531 Basics ofFastConvolution 158 532 FastConvolutionofLongSequences 161 533 Filter Design by Frequency Sampling 167 54 Multi-complementary Filter Bank 168 541 Principles 168 542 Example: Eight-bandMulti-complementary Filter Bank 175 55 Java Applet – Audio Filters 180 56 Exercises 181 References 185 6 Room Simulation 191 61 Basics 191 611 RoomAcoustics 191 612 Model-based Room Impulse Responses 192 613 Measurement of Room Impulse Responses 193 614 Simulation of Room Impulse Responses 194 62 EarlyReflections 195 621 Ando’s Investigations 195 622 GerzonAlgorithm 195 63 SubsequentReverberation 200 631 SchroederAlgorithm 200 632 GeneralFeedbackSystems 208 633 FeedbackAll-passSystems 212 64 Approximation of Room Impulse Responses 213 65 JavaApplet–FastConvolution 217 66 Exercises 217 References 219 7 Dynamic Range Control 225 71 Basics 225 72 StaticCurve 226 73 DynamicBehavior 228 731 Level Measurement 228 732 GainFactorSmoothing 230 733 TimeConstants 230 74 Implementation 231 741 Limiter 231 742 Compressor,Expander,NoiseGate 231 743 CombinationSystem 233 75 RealizationAspects 234 751 SamplingRateReduction 234 752 CurveApproximation 236 753 StereoProcessing 237 76 JavaApplet–DynamicRangeControl 237 77 Exercises 238 References 239 8 Sampling Rate Conversion 241 81 Basics 241 811 Upsampling and Anti-imaging Filtering 241 812 Downsampling and Anti-aliasing Filtering 242 82 Synchronous Conversion 244 83 Asynchronous Conversion 246 831 Single-stage Methods 250 832 Multistage Methods 252 833 Control of Interpolation Filters 253 84 InterpolationMethods 257 841 Polynomial Interpolation 257 842 LagrangeInterpolation 260 843 Spline Interpolation 261 85 Exercises 269 References 270 9 Audio Coding 273 91 LosslessAudioCoding 273 92 LossyAudioCoding 275 93 Psychoacoustics 277 931 CriticalBands andAbsoluteThreshold 277 932 Masking 279 94 ISO-MPEG-1AudioCoding 284 941 Filter Banks 285 942 PsychoacousticModels 287 943 DynamicBitAllocationandCoding 290 95 MPEG-2AudioCoding 291 96 MPEG-2AdvancedAudioCoding 292 97 MPEG-4AudioCoding 304 98 SpectralBandReplication 306 99 JavaApplet–Psychoacoustics 308 910 Exercises 310 References 311