简介：Becauseofquickdevelopmentofcities,theupdateofurbanGISdataisveryimportant.Changedetectionisthebaseofautomaticorsemi-automaticdataupdate.Onewayofchangedetectionsinurbanareaisbasedonoldandnewaerialimagesacquiredindifferentdurations.Thecorrespondingtheoryandexperimentsareintroducedandanalyzedinthispaper.Themainprocedureincludesfourstages.Thenewandoldimageshavetoberegisteredfirstly.Thenimagematching,basedonthemaximumcorrelationcoefficient,isperformedbetweenregisteredimagesafterthelowcontrastareashavebeenremoved.Theregionswithlowmatchingqualityareextractedascandidatechangedareas.Thirdly,theGaussian-Laplacianoperatorisusedtodetectedgesincandidatechangedareasonboththeregisteredimages,andthestraightlinesaredetectedbyHoughtransformation.Finally,thechangedhousesandroadscanbedetectedonthebasisofstraightlinematchingincandidatechangedareasbetweenregisteredimages.