speech coding algorithms foundation and evolution of standardized coders

[...]... development of next-generation algorithms, with improvements in all aspects This chapter is organized as follows: an overview of speech coding is provided first, with the structure, properties, and applications of speech coders explained; the different classes of speech coders are described next, followed by speech production and modeling, covering properties of speech signals and a very simple coding system... developed for speech coding have also been applied to other application areas such as speech synthesis, audio coding, speech recognition, and speaker recognition Due to the weighty position that speech coding occupies in modern technology, it will remain in the center of attention for years to come 1.2 CLASSIFICATION OF SPEECH CODERS The task of classifying modern speech coders is not simple and is often confusing,... overview of the subjects covered, with references to various aspects of speech coding, standards, algorithms, and comments on notation and terminology Chapter 2 is a review of some signal processing techniques, some are very general, but others are less known outside speech coding literature Chapter 3 contains some foundation for stochastic processes and models, which are important for an understanding of. .. system High-level explanation of the human auditory system is given, where the system properties are used to develop efficient coding schemes Activities of standard bodies and many standardized coders are discussed in the next section, followed by issues related to analysis and implementation of algorithms A brief summary is given at the end of the chapter 1.1 OVERVIEW OF SPEECH CODING This section describes... directly at the hardware level The purpose of this book is to explain the theoretical issues and implementational techniques related to the fascinating field of speech coding The topics of discussion are focused on some of the well-established and widely used speech coding standards By studying the most successful standards and understanding their principles, performance, and limitations, it is possible to... properties, and applications of speech coding technology Structure of a Speech Coding System Figure 1.1 shows the block diagram of a speech coding system The continuoustime analog speech signal from a given source is digitized by a standard connection Speech source Filter Sampler A/D converter Source encoder Channel encoder Channel Channel decoder Source decoder D/A converter Filter Figure 1.1 Block diagram of. .. support its operation, as well as computational demand Speech coding researchers spend a great deal of effort to find out the most efficient realizations  Low Coding Delay In the process of speech encoding and decoding, delay is inevitably introduced, which is the time shift between the input speech of the encoder with respect to the output speech of the decoder An excessive delay creates problems with... transmission and burst mode transmission, respectively Applications of Speech Coders Speech coding has an important role in modern voice-enabled technology, particularly for digital speech communication, where quality and complexity have a direct impact on the marketability and cost of the underlying products or services There 8 INTRODUCTION are many speech coding standards designed to suit the need of a given... for speech coding, with the objectives of overcoming deficiencies and limitations The standardization community pursues the establishment of standard speech coding methods for various applications that will be widely accepted and implemented by the industry The business communities capitalize on the ever-increasing demand and opportunities in the consumer, corporate, and network environments for speech. .. sincere hope is that the availability of a book that collects many of the techniques used in speech coding and presents them in an accessible fashion will create excitement and enthusiasm, ensuring continuous rapid advances in the field Philosophy and Approach Speech Coding Algorithms reflects the core subject of the book, since most coding techniques are implemented as algorithms, or computational procedures . California A JOHN WILEY & SONS, INC., PUBLICATION SPEECH CODING ALGORITHMS SPEECH CODING ALGORITHMS Foundation and Evolution of Standardized Coders WAI C. CHU Mobile Media Laboratory DoCoMo USA. Overview of Speech Coding / 2 1.2 Classification of Speech Coders / 8 1.3 Speech Production and Modeling / 11 1.4 Some Properties of the Human Auditory System / 18 1.5 Speech Coding Standards /. coding algorithms: Foundation and evolution of standardized coders ISBN 0-471-37312-5 Printed in the United States of America 10987654321 Intelligence is the fruit of industriousness Accretion of