Research on Dynamic Targets Tracking Based on Color Cues Under Complicated Scene

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1 Available online a Procedia Engineering 6 (0 ) Inernaional Workshop of Aoobile Power and Energy Engineering Research on Dynaic Targes Tracking Based on Color Ces Under Coplicaed Scene Yi Wang * Yingw Fang Xiny Da Shxin Chen Hi Wang Teleconicaion Engineering Insie Air Force Engineering Universiy s Fenghao Road No.6 Xi an China Absrac Copared wih DST DST can be good evidence of conradicions o resolve he isse of evidence porfolios In view of he occlding in racking dynaic arges in coplex backgrond a new ani-occlding arge racking algorih based on DST and paricle filer is proposed by color ces. The silaion resls show ha he proposed algorih is effecive and pracicable in racking occlded arge and inerseced arge. Copared wih he exising cobinaion rles he newly proposed rle is applied o boh cases of conflicing and coincidence. 00 Pblished by Elsevier Ld. Selecion and/or peer-review nder responsibiliy of Sociey for Aoobile Power and Energy Engineering Open access nder CC BY-NC-ND license. Keywords: DST; color ces; dynaic arges; racking. Inrodcion The visal obec racking is a key isse in any vision-based applicaions sch as visal srveillance visal navigaion of robos han-coper ineracion edical diagnose and iliary gidance []. Along wih he rapid growh of he inforaion echniqes in he las ens of years he obec racking has araced any researchers aenion and has becoe a very poplar research opic. Alhogh any effecive visal obec racking ehods has been proposed here are sill a lo of difficlies in designing a robs racking algorih de o he challenging coplex scenarios sch as significan illinaion changes in environen pose variaions of he obec and non-linear deforaions of shapes and noise and dense clers in coplex backgrond ec. DST is a sefl ehod for dealing wih ncerainy probles []. I is ore efficien in cobining conflicing evidence; herefore i has been sccessflly applied in dynaic arges racking. * Corresponding ahor. Tel.: E-ail address: fangyw7@6.co Pblished by Elsevier Ld. doi:0.06/.proeng Open access nder CC BY-NC-ND license.

2 60 Yi Wang e al. / Procedia Engineering 6 ( 0 ) In his paper a racking algorih based on he DST heory is proposed by adaping color ces. The dynaic racking odel wih he aor colors ces of he arges is bil so ha he arges can be represened wih a few of he odel paraeers and is perforance is sperior o he hisogra sed widely in arges racking. The proposed racking algorih can rack arges robsly in coplex scenarios sch as appearance change and occlsions by differen racking experiens.. Dynaic Targes Tracking Highly non-linear and non-gassian esiaion probles are biqios in arge racking. Paricle filers (PF) is an effecive ool for sch probles and he basic heory of PF can be fonded in lierares [34]. In order o handle real-ie racking proble effecively nder occlsion condiions and degrade he ncerainy non-inegraliy and indefinieness. A key echniqe in inforaion fsion and several racking probles nder occlsion condiion are sdied based on he fraework of PF and DST and he corresponding odel will be esablished in his paper and a general fraework for dynaic arges racking sing color ces will be described. This approach ses he DST cobinaional rle o refer he inforaion provided by he color ces ino a single represenaion and his laer akes ino accon he conflics beween he ces ha igh arise de o occlsion. Le s asse ha he nber of arges is τ he nber of ces is c and he τ and c are known. Up o ie - each arge is associaed wih a rack { }. A ie an iage frae is exraced fro he = video seqence and a nber of easreens are obained for each arge candidae. A single ap fncion can be derived as follows based o DST cobinaional rle. ( A ) = ( ) ( ) c ( ). () ( ) Where n ( A) is he overall confidence level wih which all ces associae paricle n o hypohesis A a ie. Since he arge candidaes s be associaed o individal racks he inforaion conained in copond hypoheses is ransferred ino single hypoheses hrogh he noions of he belief or plasibiliy fncions [5].. () Bel ( ) = ( A ) Pls i A Θ A D i A Θ A D. (3) ( ) = ( A ) Where Bel ( ) (resp. Pls ( ) ) qanifies he confidence wih which paricle n is associaed o θ a ie sing he noion of belief (resp. plasibiliy). The confidence levels are no sed o deerine wheher a given a candidae is he bes esiae or no of he arge hey are raher sed o qanify he weigh of he candidae as a saple of he sae poserior disribion p(x Z ). The paricle filering algorih based on DST is ipleened in his paper and he corresponding sep is given below. S = s for each arge = τ Sep : Iniializaion generae N saples { } N n independenly wih N and se =. = / S Sep : Propagaion = A S + w Sep 3: Observaion (for each paricle) Cope { ( A )} c l l = = ( A ) and { } c l l for A D Θ and =

3 Yi Wang e al. / Procedia Engineering 6 ( 0 ) ( Calclae he paricle weigh = Bel ( ) Noralize he weigh: ~ p Sep 4: Esiaion Targe = τ is given by E[ S ] = ~ s S s N n = Sep 5: Resapling (for each arge) Generae { } N n ( ) ( ) ~ n s = s = Sep 6: Increening when = + go o sep. 3. Color Ces for Tracking For wo arges we can define Θ as follows Θ =. { } ~ n ) = N ~ n = = by resapling N ies where = In (4) θ refers he firs arge θ refers o he second arge and refers o he res of he scene. Acally hypohesis can refer o he backgrond inforaion. However since his laer can change dring he racking we will refer o as he false alar hypohesis. Beside de o he possible occlsion and = for =. Le s asse ha boh arge odels are known and given by noralized color hisogras{ q ( ) where is a discree color index and is he nber of hisogra bins. A ie he noralized color ( s is given by{ n ) h } ( ) hisogra of paricle. The probabiliy ha paricle = belongs o arge = according o he color hisogra is derived fro he following Gassian pdf. p ( d ) e = = where σ is a color bandwidh paraeer ie. d = q } FA ( ) = Le s define { and. s (4) } =. (5) ( ) d is he Bhaacharyya disance beween ( ) h n and () a = h ( ) q ( ). (6) as he hisogra of he scene fro which we sbrac he hisogra of arges { q ( ) q ( ) q ( )0} qfa( ) ax scene s ( d FA ) ( ) n p FA e The probabiliy ha =. (7) belongs o he false alar hypohesis will be given by =. (8) q

4 6 Yi Wang e al. / Procedia Engineering 6 ( 0 ) FA FA = Where d = h ( ) q ( ) The ass fncions of paricle n according o color can be evalaed as follows p. (9) FA ( ) = p + p + p FA ( ) = p = ( ) ( ) ( ) p + p + p n n n. (0) FA 4. Tracking Experien and Analysis In order o es racking efficiency and correcness wo differen videos wih he sae scene are seleced o copare he inrodced ehod as shown in figre and figre. There are only wo people in he firs video and here are any people in he second video and wo inersecing arges will be arked. Fig. Two arges of he firs video Fig. Two arges of he second video Owing o he increased nber of paricles will increase he processing ie 0 paricles are sing o dynaic arges racking in he firs video by he above analysis and 30 paricles are given o ee he accracy of dynaic racking in he second video. The dynaic racking process of ain frae is given and figre 3 is he firs video and figre 4 is he second video respecively. Fig.3 The racking process of ain fraes in he firs video Fig.4 The racking process of ain fraes in he second video A las he dynaic racking resl of inersecing arges in clered scenes is goen and figre 5 is

5 Yi Wang e al. / Procedia Engineering 6 ( 0 ) he firs scene and figre 6 is he second scene respecively. Fig.5 The resl of inersecing arges in he firs video Fig.6 The resl of inersecing arges in he second video I can be seen fro he above racking process he inrodced ehod accraely idenifies he arges dring he hree phases of he racking. This is de o he effecive handling of he conflicing inforaion provided by he color ces based on he DST. 5. Conclsion Highly non-linear and non-gassian esiaion probles are biqios in dynaic arge racking and i is a ogh ob o selec he characerisics of arges in arge racking syse. If arges have ore feares racking accracy cold be iproved effecively. However coping qaniy and calclaion ie wold also be increased. I is iperaive for s o ake coproise of real-ie and accracy. As high sabiliy and low copaion al characerisics color ces are becoe ain inforaion and i can be sed o esablish dynaic arges racking odel based on DST wih he DST is very effecive evidence heory for sch probles. The experienal resls have been deonsraed ha his ehod aelioraed he inerference iniy of he radiional odel for racking arges. The inrodced ehod iproved he racking accracy and robsness while no affecing he real-ie characerisics and i have beer dynaic racking effec for differen scenes. Acknowledgeens The proec is sppored by he Science Fondaion of he Teleconicaion Engineering Insie of Air Force Engineering Universiy (No.DYCX005) and he ahors are very graefl o he fondaion.

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