Noise is everywhere and in most applications that are related to audio and speech, such as human-machine interfaces, hands-free communications, voice over IP (VoIP), hearing aids, teleconferencing/telepresence/telecollaboration systems, and so many others, the signal of interest (usually speech) that is picked up by a microphone is generally contaminated by noise. As a result, the microphone signal has to be cleaned up with digital signal processing tools before it is stored, analyzed, transmitted, or played out. This cleaning process is often called noise reduction and this topic has attracted a considerable amount of research and engineering attention for several decades. One of the objectives of this book is to present in a common framework an overview of the state of the art of noise reduction algorithms in the single-channel (one microphone) case. The focus is on the most useful approaches, i.e., filtering techniques (in different domains) and spectral enhancement methods. The other objective of Noise Reduction in Speech Processing is to derive all these well-known techniques in a rigorous way and prove many fundamental and intuitive results often taken for granted. This book is especially written for graduate students and research engineers who work on noise reduction for speech and audio applications and want to understand the subtle mechanisms behind each approach. Many new and interesting concepts are presented in this text that we hope the readers will find useful and inspiring.

Noise and distortion that degrade the quality of speech signals can come from any number of sources. The technology and techniques for dealing with noise are almost as numerous, but it is only recently, with the development of inexpensive digital signal processing hardware, that the implementation of the technology has become practical. Noise Reduction in Speech Applications provides a comprehensive introduction to modern techniques for removing or reducing background noise from a range of speech-related applications. Self-contained, it starts with a tutorial-style chapter of background material, then focuses on system aspects, digital algorithms, and implementation. The final section explores a variety of applications and demonstrates to potential users of the technology the results possible with the noise reduction techniques presented. The book offers chapters contributed by international experts, a practical, systems approach, and numerous references. For electrical, acoustics, signal processing, communications, and bioengineers, Noise Reduction in Speech Applications is a valuable resource that shows you how to decide whether noise reduction will solve problems in your own systems and how to make the best use of the technologies available.

This guide offers practical solutions for ordinary noise problems that a person is likely to meet. The book describes the ways in which sounds are generated, travel to the listener, and affect his hearing and well-being. Recommendations are given for controlling noise at the source and along its path of travel, and for protecting the listener. This guide instructs the reader by way of "Warning Sings" on how to determine whether he is being subjected in his environment to prolonged noise exposures that may prove hazardous to his hearing.Remedies are given for noise problems that a person is likely to find in his home, at work and at school, while traveling, and in the growth and development of his community. The remedies include noise prevention techniques and selection of quiet alternatives to existing noise sources. General principles for selecting quiet appliances are given. Ways of searching for the sources of noise and for determining the paths over which they travel to the listener are described. A detailed index is given for individual ways of looking for inherently quiet homes and travel accomodations are described.In a final chapter, there are suggestions for enlisting community help where large external sources of noise must be quieted, such as those arisseing from public utilities and public transportation.

The field of acoustics has many branches, but none is developing more rapidly than noise control. Noise has assumed an importance in national thinking that could hardly have been believed two decades ago. The control of noise must be considered at all stages of the design and engineering of airports, aircraft, buildings, home appliances, industrial machinery, automobiles, and cities--particularly in residential and industrial areas. This book, which is intended to be readable by graduate engineers in nearly any technical field, presents the material in graded technical levels, with simpler concepts, apparatus, and techniques appearing first, followed by more specialized and complex techniques. No effort has been made to produce a handbook or all-inclusive compendium. Rather, this text seeks to lead the reader by gradual steps from the beginning of the subject into the more advanced aspects. The text contains many numerical examples and frequent comparison of measured with calculated data and gives practical details of construction.

Though noise reduction and speech enhancement problems have been studied for at least five decades, advances in our understanding and the development of reliable algorithms are more important than ever, as they support the design of tailored solutions for clearly defined applications. In this work, the authors propose a conceptual framework that can be applied to the many different aspects of noise reduction, offering a uniform approach to monaural and binaural noise reduction problems, in the time domain and in the frequency domain, and involving a single or multiple microphones. Moreover, the derivation of optimal filters is simplified, as are the performance measures used for their evaluation.

Acoustics and Noise Control provides a detailed and comprehensive introduction to the principles and practice of acoustics and noise control. Since the last edition was published in 1996 there have been many changes and additions to standards, laws and regulations, codes of practice relating to noise, and in noise measurement techniques and noise control technology so this new edition has been fully revised and updated throughout. The book assumes no previous knowledge of the subject and requires only a basic knowledge of mathematics and physics. There are worked examples in the text to aid understanding and a range of experiments help students use complicated apparatus. Thoroughly revised to cover the latest changes in standards, codes of practice and legislation, this new edition covers much of the Institute of Acoustics Diploma syllabus and has an increased emphasis on the legal issues relating to noise control.

Presents Evidence-Based Guidance on Noise Abatement MethodsSolutions for reducing the noise impact of road and rail traffic can be found in the use of natural elements in combination with artificial elements in urban and rural environments. Ground and road surface treatments; trees, forests, and tall vegetation; and the greening of buildings and ot