Robust wide baseline stereo from maximally stable extremal r(6)

时间:2025-04-03

The wide baseline stereo problem ,i.e.the problem of establishing correspondences between apair of images taken from different view points is studied.A new set of image elements that are put into correspondence,the so called extremal regions,is introduced.Extremal regions possess highly desirable properties

766

J.Matasetal./ImageandVisionComputing22(2004)761–767

Table3

Experimentalresults

TC

RoughRoughEGþcorrFineEGFined’MissEGd’

Bookshelf85250.48

151630.091Valbonne49270.17180820.080Wash171420.34220860.082Kampa303780.344221850.082Cyl.box63230.15102670.093Shout15144

0.43

220

86

0.08

1

Fordetails,seethetextatthebeginningofSection4.

Afterestablishingthe‘roughEG’theso-called‘guidedmatching’stepisapplied[2,5].Intheprocessof ndingtentativecorrespondences,atmostasinglecorrespondingregionisassociatedwithoneDR.Oftenthisassociationiserroneous,forinstanceifthereisarepetitivepatterninthescene.MoreoversomeDRsarenotmatchedatallsincetheyfailthe‘mutuallynearest’requirement.Giventhe‘roughEG’,evenratherimprecise,theprocessof ndingtentativematchescanberevisited.Theoriginaltentativecorrespon-dencesarediscardedandallpotentialmatchesconsistentwiththe‘roughEG’areselected.Thematchingnowneednotrelyonrotationalinvariants,sinceepipolarlinespassingthroughapairofmatchingregionsde netheirrelativeorientation[2].The‘guided’tentativecorrespondencesarethereforeselectedusingcorrelation.

Thecolumnheaded‘EGþcorr’givesthenumberofcorrespondencesconsistentwithroughEGthatpassedthecorrelationtest.Noticethatthenumbersaremuchhigherthanthoseinthe‘roughEG’column.The nalnumberofcorrespondencesisgiveninthepenultimatecolumn‘ neEG’.Averagedistancesfromepipolarlinesarepresentedincolumns‘roughd’’and‘ ned’’.Wecansee,thattheprecisionoftheestimatedEGisveryhigh,muchhigherthantheprecisionoftheroughEG.Thelastcolumnshowsthenumberofmismatches(foundmanually).

5.Conclusions

Anewmethodforwide-baselinematchingwasproposed.Thethreemainnoveltiesare:theintroductionofMSERs,robustmatchingoflocalfeaturesandtheuseofmultiplescaledmeasurementregions.

TheMSERsaresetsofimageelements,closedundertheaf netransformationofimagecoordinatesandinvarianttoaf netransformationofintensity.Anef cient(nearlinearcomplexity)andpracticallyfastdetectionalgorithmwaspresented.ThestabilityandhighutilityofMSERswasdemonstratedexperimentally.Anothernoveltyoftheapproachistheuseofarobustsimilaritymeasureforestablishingtentativecorrespondences.Duetotherobust-ness,wewereabletoconsiderinvariantsfrommultiple

measurementregions,evensomethatweresigni cantlylarger(andhenceprobablydiscriminative)thantheassociatedMSER.

GoodestimatesofEGwereobtainedonchallengingwide-baselineproblemswiththerobusti edmatchingalgorithmoperatingontheoutputproducedbytheMSERdetector.Theaveragedistancefromcorrespondingpointstotheepipolarlinewasbelow0.09oftheinter-pixeldistance.Signi cantchangeofscale(3.5£),illuminationconditions,out-of-planerotation,occlusion,locallyaniso-tropicscalechangeand3Dtranslationoftheviewpointareallpresentinthetestproblems.Testimagesincludedbothoutdoorandindoorscenes,somealreadyusedinpublishedwork.

Acknowledgements

TheauthorsweresupportedbytheEuropeanUnionprojectIST-2001-32184,bytheGrantAgencyoftheCzechRepublicprojectGACR102/02/1539andbytheAustrianMinistryofEducationprojectCONEXGZ45.535.TheSHOUTandWASHimageswerekindlymadeavailablebyTinneTuytelaars.

References

[1]A.Baumberg,Reliablefeaturematchingacrosswidelyseparated

views,in:CVPR’00,2000,pp.I:774–781.

[2]O.Chum,T.Werner,T.Pajdla,Jointorientationofepipoles,in:

ProceedingsofBMVC’03,vol.1,BMVA,London,UK,September2003,pp.73–82.

[3]Y.Dufournaud,C.Schmid,R.Horaud,Matchingimageswith

differentresolutions,in:CVPR’00,2000,pp.I:612–618.

[4]W.E.L.Grimson,ObjectRecognition,MITPress,Cambridge,MA,

1990.

[5]R.Hartley,A.Zisserman,MultipleViewGeometryinComputer

Vision,CambridgeUniversityPress,Cambridge,UK,2000.

[6]T.LindebergandJ.Ga

rding,“Shape-adaptedsmoothinginestimationof3-Ddepthcuesfromaf nedistortionsoflocal2-Dstructure”,inProc.3rdEuropeanConferenceonComputerVision,vol.800ofLectureNotesinComputerScience,(Stockholm,Sweden),pp.389–400,SpringerVerlag,1994.

[7]D.Lowe,Objectrecognitionfromlocalscale-invariantfeatures,in:

ICCV’99,1999,pp.1150–1157.

[8]J.Matas,P.B

´lek,O.Chum,Rotationalinvariantsforwide-baselinestereo,in:ProceedingsofCVWW’02,February2002,pp.296–305.

[9]J.Matas,S

ˇ.Obdrzˇ´alek,O.Chum,Localaf neframesforwide-baselinestereo,in:ProceedingsofICPR,vol.4,IEEECS,August2002,pp.363–366.

[10]K.Mikolajczyk,C.Schmid,Indexingbasedonscaleinvariantinterest

points,in:EighthInternationalConferenceonComputerVision,Vancouver,Canada,2001.

[11]K.Mikolajczyk,C.Schmid,Anaf neinvariantinterestpointdetector,

in:ProceedingsofECCV,vol.1,2002,pp.128–142.

[12]F.Mindru,T.Moons,L.vanGool,Recognizingcolorpatterns

irrespectiveofviewpointandillumination,in:CVPR’99,1999,pp.I:368–373.

…… 此处隐藏:2774字,全部文档内容请下载后查看。喜欢就下载吧 ……
Robust wide baseline stereo from maximally stable extremal r(6).doc 将本文的Word文档下载到电脑

精彩图片

热门精选

大家正在看

× 游客快捷下载通道(下载后可以自由复制和排版)

限时特价:7 元/份 原价:20元

支付方式:

开通VIP包月会员 特价:29元/月

注:下载文档有可能“只有目录或者内容不全”等情况,请下载之前注意辨别,如果您已付费且无法下载或内容有问题,请联系我们协助你处理。
微信:fanwen365 QQ:370150219