This page intentionally left blank Cellular neural networks and visual computing Cellular Nonlinear/neural Network (CNN) technology is both a revolutionary concept and an experimentallyprovennewcomputingparadigm.AnalogiccellularcomputersbasedonCNNsare settochangethewayanalogsignalsareprocessedandarepavingthewaytoanentirenewanalog computingindustry. Thisuniqueundergraduate-leveltextbookincludesmanyexamplesandexercises,includingCNN simulatoranddevelopmentsoftwareaccessibleviatheInternet.ItisanidealintroductiontoCNNs and analogic cellular computing for students, researchers, and engineers from a wide range of disciplines.Althoughitsprimefocusisonvisualcomputing,theconceptsandtechniquesdescribed inthebookwillbeofgreatinteresttothoseworkinginotherareasofresearch,includingmodeling ofbiological,chemical,andphysicalprocesses. Leon Chua is a Professor of Electrical Engineering and Computer Science at the University of California,BerkeleywherehecoinventedtheCNNin1988andholdsseveralpatentsrelatedtoCNN Technology.HereceivedtheNeuralNetworkPioneerAward,2000. Tama´s Roska is a Professor of Information Technology at the Pa´zma´ny P. Catholic University of Budapest and head of the Analogical and Neural Computing Laboratory of the Computer and AutomationResearchInstituteoftheHungarianAcademyofSciences,Budapestandwasanearly pioneer of CNN technology and a coinventor of the CNN Universal Machine as an analogic supercomputer, He has also spent 12 years as a part-time visiting scholar at the University of CaliforniaatBerkeley. Cellular neural networks and visual computing Foundation and applications Leon O. Chua and Tama´s Roska The Pitt Building, Trumpington Street, Cambridge, United Kingdom The Edinburgh Building, Cambridge CB2 2RU, UK 40 West 20th Street, New York, NY 10011-4211, USA 477 Williamstown Road, Port Melbourne, VIC 3207, Australia Ruiz de Alarcón 13, 28014 Madrid, Spain Dock House, The Waterfront, Cape Town 8001, South Africa http://www.cambridge.org ©Cambridge University Press 2004 First published in printed format 2002 ISBN 0-511-04051-2 eBook (netLibrary) ISBN 0-521-65247-2 hardback Toourwives,DianaandZsuzsa Contents Acknowledgements pagexi 1 Introduction 1 2 Notation,definitions,andmathematicalfoundation 7 2.1 Basicnotationanddefinitions 7 2.2 Mathematicalfoundations 14 3 CharacteristicsandanalysisofsimpleCNNtemplates 35 3.1 Twocasestudies:theEDGEandEDGEGRAYtemplates 35 3.2 ThreequickstepsforsketchingtheshiftedDPplot 49 3.3 Someotherusefultemplates 50 4 SimulationoftheCNNdynamics 100 4.1 IntegrationofthestandardCNNdifferentialequation 100 4.2 Imageinput 101 4.3 Softwaresimulation 102 4.4 Digitalhardwareaccelerators 110 4.5 AnalogCNNimplementations 111 4.6 Scalingthesignals 113 4.7 Discrete-timeCNN(DTCNN) 114 vii viii Contents 5 BinaryCNNcharacterizationviaBooleanfunctions 115 5.1 BinaryanduniversalCNNtruthtable 115 5.2 Booleanandcompressedlocalrules 122 5.3 Optimizingthetruthtable 124 6 UncoupledCNNs:unifiedtheoryandapplications 139 6.1 Thecompletestabilityphenomenon 139 6.2 ExplicitCNNoutputformula 140 6.3 ProofofcompletelystableCNNtheorem 142 6.4 TheprimaryCNNmosaic 155 6.5 Explicitformulafortransientwaveformandsettlingtime 156 6.6 WhichlocalBooleanfunctionsarerealizablebyuncoupledCNNs? 161 6.7 Geometricalinterpretations 162 6.8 HowtodesignuncoupledCNNswithprescribedBooleanfunctions 166 6.9 Howtorealizenon-separablelocalBooleanfunctions? 173 7 IntroductiontotheCNNUniversalMachine 183 7.1 Globalclockandglobalwire 184 7.2 Setinclusion 184 7.3 Translationofsetsandbinaryimages 188 7.4 Openingandclosingandimplementinganymorphologicaloperator 190 7.5 ImplementinganyprescribedBooleantransitionfunctionbynotmorethan 256templates 195 7.6 Minimizing the number of templates when implementing any possible Booleantransitionfunction 198 7.7 Analog-to-digitalarrayconverter 201 8 Backtobasics:Nonlineardynamicsandcompletestability 205 8.1 Aglimpseofthingstocome 205 8.2 AnoscillatoryCNNwithonlytwocells 205 8.3 AchaoticCNNwithonlytwocellsandonesinusoidalinput 210 8.4 SymmetricAtemplateimpliescompletestability 214 8.5 Positiveandsign-symmetricAtemplateimpliescompletestability 219