Rate-Quality Optimized Video Coding

198 Pages·1999·13.18 MB·English

by  Yoo-Sok Saw (auth.)

RATE-QUALITY OPTIMIZED
VIDEO CODING
THE KLUWER INTERNATIONAL SERIES
IN ENGINEERING AND COMPUTER SCIENCE
RA TE-QUALITY OPTIMIZED
VIDEO CODING
by
Yoo-SokSaw
LG lnformation and Communications, Ltd.
Republic of Korea
SPRINGER SCIENCE+BUSINESS MEDIA, LLC
ISBN 978-1-4613-7332-2 ISBN 978-1-4615-5125-6 (eBook)
DOI 10.1007/978-1-4615-5125-6
Library of Congress Cataloging-in-Publication Data
A C.I.P. Catalogue record for this book is available
from the Library of Congress.
Copyright © 1999 by Springer Science+Business Media New York
Originally published by Kluwer Academic Publishers in 1999
Softcover reprint ofthe hardcover 18t edition 1999
AII rights reserved. No part of this publication may be reproduced, stored in a
retrieval system or transmitted in any form or by any means, mechanical, photo
copying, recording, or otherwise, without the prior written permission of the
publisher, Springer Science+Business Media, LLC.
Printed on acid-free paper.
Contents
List ofFigures VII
List ofTables XI
Preface XIII
Acknowledgments XV
Foreword XVII
Introduction XIX
Digitalvideo compression and rate adaptation
Part I Background ofvideo rate-quality optimisation
1. NON-STATIONARY NATURE OF DIGITAL VIDEO 3
1.1 Introduction 3
1.2 Compressed video and its non-stationarity 5
1.3 Summary 13
2. RATE-QUALITY CONTROL IN INTERNATIONAL STANDARDS 15
2.1 Introduction 15
2.2 Real-time video compression techniques 16
2.3 Transmission ofcompressed video via rate management 23
2.4 A review ofvideo traffic management techniques 24
2.5 A comparative review of rate control mechanisms employed in compression
~~~ ~
2.6 Summary 32
3. QUANTISER CONTROL FOR RATE-QUALITY OPTIMISATION 33
3.1 Introduction 33
3.2 Ratecontrol via adaptive quantisation 34
3.3 Nonlinearity ofthe MPEG video encoding process 38
3.4 Two rate control approaches 39
3.5 Rate and quantisercontrol schemes 41
3.6 Configuration for simulation 42
3.7 Summary 44
4. LINEAR PREDICTIVE VIDEO RATE ESTIMATION AND CONTROL 45
Vi RATE-QUALITY OPTIMIZEDVIDEO CODING
4.1 Introduction 45
4.2 Variable bit rate video coding 46
4.3 Coding parametersassociated with the rate control 48
4.4 MPEG-1 encoder usingfeed-forward rate control and scene change features 51
4.5 Simulation results 61
4.6 An encoder model based on a stochastic interpretation 65
4.7 Limitations ofthe rate control techniqueemployed in the MPEG-2 TM5 66
4.8 System identification via linear prediction 69
4.9 Summary 77
Part II Nonlinear signal processing approachesto video rate-quality optimisation
5. NONLINEAR PREDICTIVEVIDEO RATE ESTIMATION AND CONTROL 83
5.1 Introduction 83
5.2 Configuration ofthe MPEG-2 encoder based on a rateestimator 84
5.3 Rate-Distortion analysis of the quantiser control functions: sigmoidal and
unimodal 91
5.4 RBF rate estimator-based MPEG-2 video encoder 101
5.5 Simulation studies 103
5.6 Summary 106
6. FUZZY LOGIC-BASED VIDEO RATE ESTIMATION AND CONTROL 111
6.1 Introduction 111
6.2 Fuzzy rule-based control for video rate control 112
6.3 Thefuzzy control parameters 119
6.4 Improved FRC-based rate control algorithms 121
6.5 Simulation studies 131
6.6 Summary 143
7. ADVANCED TOPICS 147
7.1 Introduction 147
7.2 Major improvements achieved in nonlinear approaches 147
7.3 Advantagesand limitations ofthe nonlinear schemes 149
7.4 Futureof nonlinear approaches 150
7.5 Emerging technology issuesin video coding 151
7.6 Amodel oflab. configuration 160
7.7 Summary 161
References 163
Appendices
A-Videosequences used in simulations 175
Index 181
List of Figures
1.1 Examples ofvideo sequences. 4
1.2 Frame difference between two pictures. 5
1.3 Block partitions in a picture, macro blocks (MB) 6
1.4 MPEG coding process, illustrated. 7
1.5 Rate variation in the DCT process. 8
1.6 Rate buffering in video encoder. 8
1.7 Frame-wise entropies in bits/pel for intra-picture and frame
difference ("Miss America"), max.(frame no.)/min.(frame no.). 9
1.8 Frame-wise entropies in bits/pel for intra-picture and frame
difference ("Susie"), (frame no.)/min.(frame no.). 9
1.9 Frame-wise entropies in bits/pel for intra-picture and frame
difference ("Football"), (frame no.)/min.(frame no.). 10
1.10 A classification ofthe scene change features. 11
1.11 Examples ofthe buffer occupancy fluctuation. 12
2.1 Video conferencing system in interoperability test: left (a),
TransVision261 and System261, GPT (UK), right (b) produc-
tion sample. Courtesy from LGIC, Korea. 20
2.2 Video encoder (left) and video decoder (right) units. 20
2.3 Video input (left) and output (right) units. 20
2.4 Audio codec (left) and network interface (right) units. 21
2.5 Classification ofvideo rate and traffic management techniques. 25
3.1 Feedback buffer-based rate control scheme specified in MPEG. 35
3.2 Parameters for the buffer-based rate control. 35
3.3 An early form ofquantisation control function. 36
3.4 Simplified video encoding process. 38
3.5 Approach 1: feed-forward predictive scheme. 40
3.6 Approach 2: fuzzy logic control. 41
3.7 MPEG video encoder with rate control. 43
3.8 Configuration ofsimulation. 44
4.1 Video rate fluctuation at three channel transmission rates. 47
viii RATE-QUALITY OPTIMIZEDVIDEO CODING
4.2 Bit rate and PSNR for various quantisation scale values for
VBR ("Starwars"): (a) bit rate; (b) standard deviation ofthe
bit rate; (c) PSNR; (d) standard deviation ofPSNR. 49
4.3 Bit rate and PSNR variations depending on the quantisation
scale ("Starwars"): (a) Coded bits/frame; (b) PSNR. 50
4.4 Feed-forwardratecontrolschemefortheMPEG-1 videoencoder. 52
4.5 Frame variances var_org(k) and var_dif(k): (a) Cascaded;
(b) Starwars; (c) Adverts. 53
4.6 Directionalmotion vectorfunction, MVFD: (a) Cascaded; (b)
Starwars; (c) Adverts. 55
4.7 Frame-wise intra/inter decision using variances. 57
4.8 Occupancy for a 2-frame buffer at different transmission rates
("Football"). 59
4.9 Sigmoidal quantisation scale control. 60
4.10 Logarithmic-exponential quantisation scale control. 61
4.11 Rate control features in TM5: (a) Picture complexity mea-
sured as the product ofthe quantisation scaleand the number
of coded bits for the previous picture; (b) Normalised macro
block activity and the resulting quantisation scale. 68
4.12 A basic linear predictor. 70
4.13 Quantiser combined with the linear predictor. 70
4.14 VBR MPEG-2 encoder using the linear estimator. 71
4.15 A basic linear estimator (Type I). 71
4.16 A linear predictor, Type II. 72
4.17 A linear predictor, Type III. 73
4.18 Type III predictor with recursive least square-based weight
calculation. 73
4.19 Three inputs, var_org(k), var_dif(k) and ptype(k): (a) Cas-
caded; (b) Starwars; (c) Adverts. 75
4.20 Linear prediction Type III for "Starwars" (VBR): (a) Coded
bits/frame; (b) MSE. 76
4.21 Recursive linear prediction for "Starwars" (VBR): (a) Coded
bits/frame; (b) MSE. 77
4.22 Linear prediction TypeIII for "Starwars" at 1280kbits/s: (a)
Coded bits/frame; (b) MSE. 78
4.23 Recursivelinear predictionfor "Starwars" at 1280kbits/s: (a)
Coded bits/frame; (b) MSE. 79
5.1 ThestructureofthenonlinearpredictiveratecontrolforMPEG-
2: (a) a functional representation; (b) the signal flow. 85
5.2 Quantiser control based on the nonlinear function surface. 88
5.3 Nonlinear quantiser control surfaces: (a) Sigmoidal (Smax =
5); (b) Sigmoidal (Smax = 13); (c) Unimodal (Smax = 5); (d)
Unimodal (Smax = 13). 90
5.4 3-dimensional representation of Ds(r) and Du(r) 95
5.5 3-dimensional representation ofthe video rate fluctuation 97
LISTOFFIGURES IX
5.6 Thevariationin the bufferoccupancyfor thequantisercontrol
surfaces 100
5.7 RBF predictor with 3inputs and 9 taps. 102
5.8 MSE profile depending on the number ofcentres. 104
5.9 Performance ofrate control algorithms ("Starwars"): (a) oc-
cupancy; (b) coded bits/frame; (c) PSNR. 107
5.10 Macro block-wise variations in the quantisation scale and the
buffer occupancy ("Starwars"): (a) TM5; (b) LIN; (c) SIGM;
(d) LOGEXP; (e) RLS; (e) RBF. 108
6.1 A basic model offuzzy rule-based control. 114
6.2 Configuration of an MPEG-2 video encoder with fuzzy logic
rate control (FRC-R). 115
6.3 Configuration ofthe FRC-based rate control (FRC-R). 115
6.4 Fuzzyrule-basedcontrolparameters: (a) membershipfunction
(Type 0); (b) fuzzy associative memory map for deriving Lo. 118
6.5 Asimplified defuzzification process. 119
6.6 Membership functions with irregular-spacing: (a) wider spac
ing around the middle value (Type 1); (b) narrower spacing
around the middle value (Type 2). 121
6.7 3-dimensional representationofthefuzzy associativememory:
(a) LIN; (b) EXP; (c) LOG; (d) SGM. 122
6.8 Corresponding control surfaces to the fuzzyassociative mem-
ory in Figure 6.7: (a) LIN; (b) EXP; (c) LOG; (d) SGM. 123
6.9 The fuzzy associative memory and its control surface used for
performance improvement: (a) Allocation of fuzzy sets; (b)
resulting FAM; (c) 3 dimensional representation; (d) control
surface. 125
6.10 Scene change-based FRC for MPEG-2 video rate control. 126
6.11 Configuration ofthe scene change-based FRC (FRC-SC). 126
6.12 Configuration of the FRC based on macro-block-wise video
rate balance (FRC-B). 128
6.13 Configuration ofthe quality-monitored FRC (FRC-QM). 130
6.14 Detailed block diagram ofFRC-QM. 131
=
6.15 Distribution offuzzy sets usedfor ge,gd 4, 16in the FRC-R
scheme: (a) "Cascaded"; (b) "Starwars". 132
6.16 The effect of varying scaling factors in FRC-R ("Starwars"):
(a) occupancy; (b) coded bits/frame; (c) PSNR. 134
6.17 Performance comparison for the different membership func-
tionsinFRC-R("Starwars"): (a) occupancy; (b) codedbits/frame;
(c) PSNR. 135
6.18 Performancecomparisonfordifferentfuzzy associativememory
control surfaces in the FRC-R ("Starwars"): (a) occupancy;
(b) coded bits/frame; (c) PSNR. 137
6.19 Performance evaluation for FRC-B ("Starwars"): (a) occu-
pancy; (b) coded bits/frame; (c) PSNR. 139
x RATE-QUALITY OPTIMIZEDVIDEOCODING
6.20 Performance evaluation for FRC-Q ("Starwars"): (a) coded
bits/frame; (b) PSNR. 140
6.21 Performance comparison between FRC-Q and VBR ("Star-
wars"): (a) coded bits/frame; (b) PSNR. 141
6.22 PerformanceprofilesforFRC-R,FRC-SCandFRC-QM ("Star-
wars"): (a) occupancy; (b) coded bits/frame; (c) PSNR. 144
7.1 Heterogeneousnatureofdigital videocommunicationenviron-
ment. 152
7.2 Classification ofscalability. 153
7.3 Configuration ofthe H.324/M multimedia standard. 154
7.4 Video transcoding in digital video broadcasting. 155
7.5 Classification ofdigital video transcoding. 156
7.6 Typical transcoder architecture. 157
7.7 Mobile multimedia, medical application: diagnosis-on-demand. 159
7.8 Mobile multimedia service provision scenarios. 160
7.9 An example laboratory configuration for mobile multimedia
technology. 161
A.l Video sequence "Cascaded" (Miss America- Football - Susie) 176
A.2 Video sequence "Starwars" 177
A.3 Video sequence "Adverts" 178
A.4 Video sequence "JFK" 179
A.5 Video sequence "Topgun" 180