1st Edition

A Practical Handbook of Speech Coders

By Randy Goldberg, Lance Riek Copyright 2000

    The demand for digital speech coding algorithms grows every day, fueled by applications such as streaming speech over the Internet, Internet telephone, digital cellular telephony, wireless teleconferencing, and various multimedia applications. Until now, most of the books available on audio coding have been collections of individually authored papers. Others have discussed the fundamental coders, but neglected many of the innovations currently in use. Unlike these books, A Practical Handbook of Speech Coders offers in-depth treatment of the basics of speech coding plus the innovations to the basic methods that make the coders useful and efficient.
    The authors designed this work for engineers, scientists, and manager who need to understand the emerging speech coding techniques and telecommunication standards. However, it will prove useful to people at all levels of speech coder experience:

  • If you want to simply download the code for an existing algorithm, this book helps you evaluate the strengths and weaknesses of all publicly available codes and choose the right one, then points you to the Internet location where the code is available for download.
  • For experts who want to improve on existing coders, this book provides the parameters of current coders and the techniques to improve upon them. You can download an existing algorithm or code it using the algorithmic descriptions in the book, make your innovations, and then test the code with the procedures given.
  • If you want to become an expert and have some basic knowledge of digital signal processing, you can learn the innovative steps taken by the inventor of each coder, explore the rigorous research techniques needed to develop your own coder, and become proficient in existing vocoder technology.
  • INTRODUCTION
    SPEECH PRODUCTION
    The Speech Chain
    Articulation
    Source-Filter Model
    SPEECH ANALYSIS TECHNIQUES
    Sampling and the Speech Waveform
    Systems and Filtering
    z Transform
    Fourier Transform
    Discrete Fourier Transform
    Windowing Signal Segments
    LINEAR PREDICTION VOCAL TRACT MODELING
    Sound Propagation in the Vocal Tract
    Estimation of LP Parameters
    Transformations of LP Parameters for Quantization
    Examples of LP Modeling
    PITCH EXTRACTION
    Autocorrelation Pitch Extraction
    Cepstral Pitch Extraction
    Frequency-Domain Error Minimization
    Pitch Tracking
    AUDITORY INFORMATION PROCESSING
    The Basilar Membrane: A Spectrum Analyzer
    Critical Bands
    Thresholds of Audibility and Detectability
    Monaural Masking
    QUANTIZATION AND WAVEFORM CODERS
    Uniform Quantization
    Nonlinear Quantization
    Adaptive Quantization
    Vector Quantization
    QUALITY EVALUATION
    Objective Measures
    Subjective Measures
    Perceptual Objective Measures
    VOICE CODING CONCEPTS
    Channel Vocoder
    Formant Vocoders
    The Sinusoidal Speech Coder
    Linear Prediction Vocoder
    LINEAR PREDICTION ANALYSIS BY SYNTHESIS
    Analysis by Synthesis Estimation of Excitation
    Multi-Pulse Linear Prediction Coder
    Regular Pulse Excited LP Coder
    Code Excited Linear Prediction Coder
    MIXED EXCITATION CODING
    Multi-Band Excitation Vocoder
    Mixed Excitation Linear Prediction Coder
    Split Band LPC Coder
    Harmonic Vector Excitation Coder
    Waveform Interpolation Coding
    PERCEPTUAL SPEECH CODING
    Auditory Processing of Speech
    Perceptual Coding Considerations
    Research in Perceptual Speech Coding
    APPENDIX: RELATED INTERNET SITES

    Biography

    Goldberg\, Randy; Riek\, Lance