MultiresolutionSamplingProcedureFortheAnalysisAndSynthesisOfTextureImages
JeremyS.DeBonet
TheProblem:
Wearedevelopingnewtechniquesfortreatinginputtextureimagesasprobabilitydensityestimatorsfromwhichwecansamplenewtextures,withsimilarappearanceandstructuralproperties.
Motivation:
Thegoaloftexturesynthesisistogenerateanewimagefromanexampletexture,suchthatthenewimageissufficientlydifferentfromtheoriginalyetstillappearsasthoughitwasgeneratedbythesameunderlyingstochasticprocess.Ifsuccessful,thenewimagewilldifferfromtheoriginal,yethaveperceptuallyidenticaltexturecharacteristics.
PreviousWork:
Recentlyseveralattemptsatdevelopingsuchtechniqueshavebeensuccessfulinlimiteddomains.MostnotablyHeegerandBergen[1],whoiterativelyresamplerandomnoisetocoerceitintohavingparticularmultiresolutionorientedenergyhistograms.
Approach:
Theapproachpresentedhereusestheresultspsychophysicalmodelstoprovideconstraintsonastatisticalsamplingprocedure.Inatwo-phaseprocess,theinputtextureisfirstanalyzedbymeasuringthejointoccurrence,acrossmultipleresolutions,ofseveralofthefeaturesusedinpsychophysicalmodels.Inthesecondphase,anewtextureissynthesizedbysamplingsuccessivespatialfrequencybandsfromtheinputtexture,conditionedonthesimilarjointoccurrenceoffeaturesatalllowerspatialfrequencies.Byrearrangingtexturalcomponentsatlocationsandresolutionswherethediscriminabilityisbelowthreshold,newtexturesamplesaregeneratedwhichhavesimilarvisualcharacteristics.SeveralresultsofthismethodareshowninFigure1.
Difficulty:
Thegoaloftexturesynthesisistogenerateatexturewhichisbothrandomandperceptuallyidenticaltotheoriginaltexture.Todothisthesynthesizedtexturemustappeartohavebeengeneratedbythesameunderlyingphysicalprocessastheoriginal.However,thisprocessisunknownandthesuccessofsynthesisdependsuponitsabilitytodiscoverit.
Impact:
Fromthisresearchnewmodelsofprobabilistictexturegenerationhavedeveloped.Thesesuggestunderlyingimagerepresentationswhichcanbeusedincomputervisionandimagedatabasetechnology.
Futurework:
Newtexturediscriminationtechniques,whichisalargecomponentofgeneralimagerecognition,canbedevelopedasaresultofthisresearch.
ResearchSupport:
ResearchsupportedinpartbyDARPAcontractNo.N00014-94-1-0128.References:
[1]Heeger,D.J.andBergen,J.R.1995.Pyramidbasedtextureanalysis/synthesis.InComputerGraphics,
pages229–238.ACMSIGGRAPH.[2]DeBonet,J.S.1997.Multiresolutionsamplingprocedureforanalysisandsynthesisoftextureimages.
InComputerGraphics.ACMSIGGRAPH.
Figure1:Texturesynthesisresults.Thesmallerpatchesaretheinputtextures,andtotheirrightaresynthesizedimageswhichare4or9timeslarger.
