Videoconferencing and Videotelephony: Technology and Standards (Artech House Telecommunications Library)

598 Pages·1999·5.03 MB·English

by  Richard Schaphorst

Videoconferencing and Videotelephony :
title: Technology and Standards Artech House
Telecommunications Library
author: Schaphorst, Richard.
publisher: Artech House, Inc.
isbn10 | asin: 0890069972
print isbn13: 9780890069974
ebook isbn13: 9781580532402
language: English
Interactive multimedia, Videoconferencing,
subject
Digital communications.
publication date: 1999
lcc: QA76.76.I59S33 1999eb
ddc: 621.39/9
Interactive multimedia, Videoconferencing,
subject:
Digital communications.
Page i
Videoconferencing and Videotelephony
Technology and Standards
Second Edition
Page ii
For a complete listing of the Artech House Telecommunications
Library, turn to the back of this book.
Page iii
Videoconferencing and Videotelephony
Technology and Standards
Second Edition
Richard Schaphorst
Page iv
Library of Congress Cataloging-in-Publication Data
Schaphorst, Richard.
Videoconferencing and videotelephony : technology and standards
/ Richard Schaphorst.2nd ed.
p. cm.(Artech House telecommunications library)
Includes bibliographical references and index.
ISBN 0-89006-997-2 (alk. paper)
1. Interactive multimedia. 2. Videoconferencing. 3. Digital
communications. I. Title. II. Series.
QA76.76.I59 S33 1999
621.39'9dc21 99-17753
CIP
British Library Cataloguing in Publication Data
Schaphorst, Richard
Videoconferencing and videotelephony : technology and standards.2nd ed.
1. Videoconferencing 2. Video telephone 3. VideoconferencingStandards
4. Video telephoneStandards
I. Title
621.3'85
ISBN 0-89006-997-2
Cover design by Lynda Fishbourne
© 1999 ARTECH HOUSE, INC.
685 Canton Street
Norwood, MA 02062
All rights reserved. Printed and bound in the United States of America. No
part of this book may be reproduced or utilized in any form or by any
means, electronic or mechanical, including photocopying, recording, or by
any information storage and retrieval system, without permission in
writing from the publisher.
All terms mentioned in this book that are known to be trademarks or
All terms mentioned in this book that are known to be trademarks or
service marks have been appropriately capitalized. Artech House cannot
attest to the accuracy of this information. Use of a term in this book
should not be regarded as affecting the validity of any trademark or
service mark.
International Standard Book Number: 0-89006-997-2
Library of Congress Catalog Card Number: 99-17753
10 9 8 7 6 5 4 3 2 1
Page v
Contents
Acknowledgments xiii
1 1
Introduction
2 9
Video Teleconferencing: Benefits and System Design
2.1 Introduction 9
2.2 Benefits of Video Teleconferencing 9
2.3 Video Teleconferencing Overview 11
2.4 Video Teleconferencing Room Considerations 14
2.4.1 Room Size, Furniture, and Location 14
2.4.2 Cameras 17
2.4.3 Display System 17
2.4.4 Audio 18
2.4.5 The VTC Controller 20
2.4.6 Administration 23
2.5 Quality and Performance Considerations 23
2.5.1 General 23

Page vi
2.5.2 System Considerations 24
2.5.3 Picture Format 24
2.5.4 Common Intermediate Format 25
2.5.5 Quarter Common Intermediate Format 25
2.5.6 Frame Rate 26
2.5.7 Motion Compensation 26
2.5.8 Bit Rates 27
2.5.9 Audio 27
2.5.10 Bandwidth 28
2.5.11 Lip Sync 28
2.5.12 Echo Cancellation 28
2.5.13 Error Control 30
2.5.14 Performance Impairments 30
2.5.15 Standards to Measure the Quality of Digital TV33
Systems
2.6 Planning a VTC System 36
2.6.1 User Survey 37
2.6.2 Develop a Technical Approach 37
2.6.3 Cost Estimate 37
2.6.4 Schedule 38
2.6.5 Project Proposal 38
3 39
Video Compression Techniques
3.1 Introduction 39
3.2 Overview 40
3.2.1 Basic NTSC Scanning Format 40
3.2.2 Compression Overview 41
3.2.3 Analog-to-Digital Conversion 44
3.2.4 Pulse Code Modulation 45
3.3 Video Compression Overview 47
3.4 Predictive Coding 50
3.5 Discrete Cosine Transform 52
3.5.1 Transformation Techniques 53
3.5.2 Coding of DCT Coefficients 55