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HC VIN CÔNG NGHBƯU CHÍNH VIN THÔNG ------------------------------------ LƯU VĂN QUYN SDNG BLC KALMAN TRONG BÀI TOÁN BÁM MC TIÊU CHUYÊN NGÀNH: KTHUT VIN THÔNG Mãs: 60.52.02.08 TÓM TT LUN VĂN THC SĨ HÀ NI - NĂM 2013

Tom Tat LV ThS Luu Van Quyen

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  • HC VIN CNG NGH BU CHNH VIN THNG

    ------------------------------------

    LU VN QUYN

    S DNG B LC KALMAN

    TRONG BI TON BM MC TIU

    CHUYN NGNH: K THUT VIN THNG

    Ms: 60.52.02.08

    TM TT LUN VN THC S

    H NI - NM 2013

  • Lun vn c hon thnh ti: HC VIN CNG NGH BU CHNH VIN THNG

    Ngi hng dn khoa hc: GS.TSKH. NGUYN NGC SAN

    Phn bin 1:.

    Phn bin 2:.

    Lun vn s c bo v trc hi ng chm lun vn thc s ti

    Hc vin Cng ngh Bu chnh Vin thng

    Vo lc:.gi..ngy.thng.nm..

    C th tm hiu lun vn ti:

    - Th vin ca Hc vin Cng ngh Bu chnh Vin thng

  • 1

    M U Vi s pht trin ca khoa hc k thut. Nhu cu s dng h thng nh v v

    dn ng tr thnh mt nhu cu khng th thiu trong cuc sng ngy nay. T

    ngun gc vic theo di bm st mc tiu hin i ngy nay l s kt hp ca cc

    khoa hc k thut nhn dng mc tiu v phng php theo di i tng, bao gm

    v tr, kch thc, hnh dng vn tc ca i tng. Bm mc tiu s dng cho nhiu

    mc ch khc nhau nh v tinh gim st khng gian c s dng theo di cc

    chuyn ng ca mc tiu nht nh.

    Thi gian gn y vic ng dng b lc Kalman c lng qu o ca i

    tng qua cc khung hnh c s dng nhiu trong cc thit b in t dn dng nh

    Camera gim st, iu hng Robot, d tm mn, thit b kim tra hnh l. Cho n

    nay c nhiu cng trnh nghin cu v lnh vc bm bt mc tiu trn c s x l

    nh v cc thut ton bm theo i tng chuyn ng nh: So khp mu, Mean-

    shift, Camshift, Particle, Kalman Mi phng php c cc u im v nhc im

    khc nhau v cho hiu qu nht nh vi tng loi i tng v mc tiu theo di

    khc nhau.

    Ni dung ca lun vn c cu trc thnh cc phn nh sau:

    Chng I. Tng qut v l thuyt bm mc tiu

    Chng II. S dng b lc Kalman trong bi ton bm mc tiu

    Chng III. V d minh ho

  • 2

    CHNG I: TNG QUT V L THUYT

    BM MC TIU 1.1. Nhng khi nim c bn.

    1.1.1 nh ngha v bi ton bm mc tiu Cho mt i tng (S) c u ra l y(t) trc tc ng ca u vo u(t)

    Hnh 1.1. S ca i tng iu khin vi u vo v u ra

    Bi ton bm mc tiu cn phi tm tn hiu iu khin u vo sao cho tn

    hiu u ra ( )y t bm theo mc tiu.

    1.1.2 nh ngha v sai s Hu nh cc phng php nh gi, c lng tham s m hnh c xy

    dng trn c s p dng nguyn l v k thut tham chiu, trong xc nh mt

    hm sai s phn nh s khc lch gia m hnh v h ng hc thc.

    1.1.2.1 Phng php sai s u ra

    Hm sai s c nh ngha:

    0 ( ) ( ) ( )e t y t y t= (1.1) 1.1.2.2 Phng php sai s u vo

    Trong phng php sai s u vo khng s dng trc tip d liu o lng v

    o hm cc bc theo thi gian ca tn hiu u vo h ng hc nn khng cn phi

    quan tm n c tnh kch thch lin tc nn bi ton c lng tham s m hnh ni

    ring, nhn dng h ng hc ni chung bao gi cng c nghim.

    1.1.2.3 Phng php sai s phng trnh.

    Sai s phng trnh c nh ngha trc tip t phng trnh ng hc ca

    m hnh nh sau:

    ( ) ( ) ( ) ( ) ( )ce t H s y t K s u t= (1.2)

  • 31.1.2.4 Phng php sai s d bo

    Sai s d bo c nh ngha nh sau:

    ( ) ( )( ) ( ) ( ) ( )( )pe

    C s K se t y t u tH sD s

    = (1.3)

    1.1.3 S dng tiu ch ti u

    1.1.3.1 Khi nim

    Ch tiu cht lng J ca mt h thng c th c nh gi theo sai lch ca

    i lng iu khin, thi gian qu hay theo mt ch tiu hn hp trong iu kin

    lm vic nh hn ch v cng sut, tc , gia tc

    1.1.3.2 Tiu ch ti u tc ng nhanh (thi gian ti thiu)

    i vi bi ton ti u tc ng nhanh th ch tiu cht lng J c dng.

    0

    1T

    J dt T= = (1.6) 1.1.3.3 Tiu ch nng sut ti u.

    Nng sut y c xc nh bi cht lng ca h thng bm theo mc tiu

    trong thi gian T nht nh. Khi ch tiu cht lng J c dng.

    00 0

    [ ( ), ), ]T T

    TJ L x t ut t dt tdt = = = (1.7) 1.1.3.4 Tiu ch nng lng ti u.

    Ch tiu cht lng J i vi tiu chi nng lng ti thiu c dng.

    2

    0

    ( )T

    J u t dt= (1.10) 1.1.4 Xy dng khu phn hi. Xt mt h thng c m t bi cc phng trnh u ra v trng thi:

    x Ax Buy Cx= + =

    & (1.11)

    Chn mt lut iu khin c dng:

    ( )u r Kx= (1.12)

  • 4

    x&

    Hnh 1.3: iu khin s dng phn hi bin trng thi

    1.1.5 Xy dng iu khin bm bng phn hi trng thi. Bi ton t ra l iu khin i tng c m t:

    A

    T

    dx x budty c x

    = +=

    (1.17)

    0 1 1

    1 2

    0 0 ... 0 00 0 ... 0

    01

    ( )n

    n

    dx z udt

    a a a

    y c c c z

    = + =

    MM M M

    % % %L

    (1.18)

    Taz

    Hnh 1.4 iu khin bm vi i tng (1.18)

    i tng(1.17)

    STaz x

    u y

    Hnh 1.5 iu khin bm vi i tng (1.17)

  • 51.1.6 Bi ton tng hp h thng

    Bi ton tng hp h thng l ton b qu trnh tnh ton, la chn b sung

    thm cc khu ph hp vo h thng. h thng khi hot ng t c nhng

    yu cu cht lng ra v sai lch, thi gian p ng qu .

    1.2 Phng php bm mc tiu truyn thng.

    1.2.1 Tho lun phng php iu khin truyn thng s dng thng tin, d liu ca tn hiu u ra ca i

    tng iu khin lm tn hiu u vo a ra tn hiu iu khin i tng.

    H thng ny c biu din bi cc phng trnh sau:

    ( ) ( ) ( ) ( ) ( )x t A t x t B t u t= +& (1.25) '( ) ( ) ( )y t C t x t= (1.26)

    Hnh 1.8 H thng iu khin c in

    1.2.2 B iu khin PID: (Proportional-Integral-Derivative) Tn gi PID l ch vit tt ca ba thnh phn c bn c trong b iu khin

    (hnh 1.10a) gm khu khuch i (P), khu tch phn (I), khu vi phn (D).

    sDT

    1

    IT s

    Hnh 1.10 iu khin vi b iu khin PID

    B iu khin PID c m t c dng tng qut sau.

    0

    1 ( )( ) [ ( ) ( ) ]t

    P DI

    de tu t k e t e d TT dt

    = + + (1.28) T m hnh vo ra tng qut ta c c hm truyn ca b iu khin PID

  • 61( ) [1 s]P DI

    R s k TT s

    = + + (1.29)

    1.2.3 Chn tham s PID ti u theo sai lch bm Bi ton c nhim v xc nh cc tham s ca b iu khin PI, gm kp, TI

    trong cng thc (1.29) hoc kp, TI, TD trong cng thc (1.31) sao cho tn hiu ra y(t)

    bm c vo hiu lnh (t) mt cch tt nht theo ngha.

    2 2( ) ( ) ( ) minQ t y t e t= = (1.32)

    V bi ton thit k b iu khin PID ti u tr thnh

    arg min ( )p f p = (1.34) 1.3. Phng php bm mc tiu hin i.

    1.3.1. Tho lun phng php. L thuyt iu khin hin i s dng m t khng gian trng thi trong min

    thi gian, mt m hnh ton hc ca mt h thng vt l nh l mt cm u vo, u

    ra v cc bin trng thi quan h vi phng trnh trng thi bc mt.

    Xut pht t quan im d trin khai l trng hp lut iu khin tuyn

    tnh, c cho bi:

    u(t) = K(x(t),t) (1.36)

    Hnh 1.12: M hnh phng php iu khin hin i.

  • 71.3.2. B quan st trng thi.

    B C

    A

    B C

    A

    L

    System

    u ++

    x& xy

    x&++

    Observer

    y

    x

    x

    Hnh 1.14 B quan st trng thi Luenberger bc y

    H thng trong hnh 1.14 c nh ngha bi:

    x Ax Bu= +& (1.38) y Cx= (1.39)

    1.3.3 iu chnh trng thi (LQR) (Linear Quadratic Regulator) Kho st vn duy tr trng thi ca h thng gi tr l 0, chng tc ng

    nhiu, ng thi vi cc tiu tiu hao nng lng 0, (0)x Ax Bu x x= + =& (1.43)

    y Cx=

    0

    1min ,2

    T TJ x Qx u Ru dt = + (1.44)

    Chn lut iu khin hi tip trng thi u = - Kx, K l hng s, thay vo biu

    thc ca J

    0

    1 ( )2

    T TJ x Q K RK xdt

    = + (1.45) 1.3.4 Gii thut thit k LQG (Linear Quadratic Gausian)

    Gi s phng trnh o lng ng ra c cho bi.

  • 8wx Ax Bu = + +& (1.57)

    y Cx v= + Gi s phng trnh hi tip c trng thi y .

    u = -Kx + r (1.58)

    Nu K c chn s dng phng trnh Riccati LQR v L c chn bi s

    dng phng trnh Riccati ca b lc Kalman. iu ny c gi l thit k LQG.

    iu quan trng ca cc kt qu ny l trng thi hi tip ca K v li ca b quan

    st L c th c thit k ring r.[4]

    1.3.5 M t b c lng trng thi gim bc Cho mt h ng hc S tuyn tnh bc n m t bi

    (S) n n n n nx A x B u= +& (1.62) n n ny C x= Vi , bc ca phn ng thi iu khin v quan st c ca S, cc

    vector v ma trn c kch thc ph hp.

    Hy xc nh b nh gi trng thi (SE) bc e,

    (SE) e e e e ex A x B u= +& (1.63) e e ey C x=

    1.3.6 Gim bc phn t iu khin Cc bi ton lin quan n phn t iu khin da vo tn hiu phn hi lm

    c s ra chin lc iu khin v cn phi x l trong khu khp kn. T v tr

    xut pht ca tn hiu phn hi m trong l thuyt h thng chia ra thnh iu khin

    truyn thng v iu khin hin i

    1.4. Vai tr ca b lc Kalman

    1.4.1 t vn . Phng trnh trng thi ca i tng

    wx Ax Bu = + +& (1.72) y Cx v= + (1.73)

  • 9

    x&

    x& x

    x

    y

    Hnh1.15 B quan st trng thi ca Kalman

    Phng trnh trng thi ca khu lc Kalman:

    ( ) x Ax Bu L y yy Cx= + + =

    & (1.74)

    Mc tiu ca thit k b lc Kalman l tm li c lng L c s c lng ti

    u trong s hin din ca nhiu w(t) v v(t)

    Sai s c lng:

    ( ) ( ) ( )x t x t x t= (1.75) 1.4.2 M hnh ton hc.

    1.4.3 Qu trnh c lng trng thi. Qu trnh c lng s dng phng php mch lc Kalman trong gim st bm mc

    tiu dc chia thnh hai giai on.

  • 10

    1k x F x

    =

    1T

    k kP FP F Q

    = +

    1T Tk k kK P H ( HP H R )

    = +k k k k k x x K ( z Hx )

    = +

    1k k kP ( K H )P=

    Thc cht ca gii thut Kalman tuyn tnh l mt phng php c tnh

    quy tuyn tnh cho php c lng trng thi ca mt h thng c nhiu sao cho

    lch gia gi tr c lng v gi tr thc t l b nht.

    1.4.4 Vai tr ca b lc Kalman Lc Kalman nhm c lng gi tr ch thc ca mt ci g , bng cch d

    on gi tr ca n v tnh tin cy (hay bt nh) ca d on , ng thi o

    c gi tr (nhng b sai s v c cc nhiu), sau ly mt trung bnh c trng gia

    gi tr d on v gi tr o c c, lm gi tr c lng. C th coi n l mt

    trng hp ca suy din c iu kin kiu bayes Cc thuc tnh c bn ca b

    lc Kalman c bt ngun t cc yu cu ca c lng trng thi.

    1.5 Kt lun chng Trong chng ny lun vn nu ra c cc khi nim c bn v bi ton bm

    mc tiu, trn nhng khi nim c bn nu ra c phng php bm mc tiu

    truyn thng, phng php bm mc tiu hin i. T tm ra vai tr ca b lc

    Kalman trong bi ton bm mc tiu.

  • 11

    CHNG II: S DNG B LC KALMAN

    TRONG BI TON BM MC TIU 2.1. Cc bin th ca b lc Kalman

    2.1.1. Nguyn tc c bn Trong ng dng gim st, bm mc tiu di ng, mch lc Kalman l qu trnh lp i

    lp li bc d on v hiu chnh trng thi ca h thng [13]. Xt mt h thng i

    din bi mt khng gian trng thi nh phng trnh (2.1) v (2.2).

    xk = Fxk-1 + vk (2.1) zk = Hxk + ek (2.2)

    2.1.2. Mch lc Kalman tuyn tnh Mch lc Kalman tuyn tnh a ra mt c lng ti u cho trng thi k -tip s

    dng cng thc tuyn tnh, gi s cc bin c phn b xc sut Gaussian.

    - Gi tr trung bnh cho trng thi k tip:

    1 k kx Fx = (2.3) - Hip phng sai ca c lng k tip:

    1 Tk kP FP F Q = + (2.4) - Tnh ton li mch lc Kalman:

    1( )T Tk k kK P H HP H R = + (2.5) - Gi tr hiu chnh trung bnh:

    ( )k k k k kx x K z Hx = + (2.6) - Hiu chnh hip phng sai:

    ( )k k kP I K H P= (2.7) 2.1.3. Mch lc Kalman m rng B lc Kalman m rng thc hin theo cc bc c lng

    - Gi tr trung bnh cho trng thi k tip:

    1 k kx x = (2.8) - Hip phng sai ca c lng k tip:

    1k kP P Q = + (2.9)

  • 12- Tnh ton li mch lc Kalman:

    1( )k k kK P P R = + (2.10) - Gi tr hiu chnh trung bnh:

    ( )k k k k kx x K z x = + (2.11) - Hiu chnh hip phng sai:

    ( )k k kP I K P= (2.12) 2.1.4. Mch lc Unscented Kalman

    Nguyn tc c bn ca Unscented Kalman l bin i Unscent. V c bn, y l mt

    phng php tnh ton thng k mt bin ngu nhin sau khi bin i khng tuyn

    tnh. Cho bin ngu nhin n chiu: xk-1 vi gi tr trung bnh $ 1kx v ma trn hip

    phng sai Pk-1

    Mch lc Unscented Kalman m t trng thi vi mt tp hp ti thiu cc im

    (sigma) mu c chn lc cn thn. 2n+1 im sigma c chn xung quanh c

    lng trc , vi n l kch thc ca khng gian trng thi. Sau mt trng s

    xc sut c gn cho nhng im sigma. Tip theo, cc im sigma ny bin i

    bng cch s dng bin i Unscent a ra mt c lng mi cho bin trng thi.

    Bin trng thi sau c hiu chnh bng cch bin i cc im sigma thng qua

    cc m hnh o lng tnh ton li Kalman. Cui cng, c lng c hiu

    chnh s dng li Kalman

    2.2. Lc Kalman trong bi ton bm mc tiu theo phng php

    phn on.

    2.2.1. Tho lun bi ton.

    2.2.2 M hnh bi ton. u vo l mt chui cc khung hnh, gi nh rng khng c s thay i v

    cng nh sng v khng c hin tng che khut. Ta c th vit nh sau:

    yk(x) = yk-1(x dk(x)) ( 2.35) M hnh quan st cho khung hnh th k tr thnh.

    gk(x) = yk(x) + nk(x) ( 2.36)

  • 13 Cn phi c lng phn phi xc xut c iu kin kt hp ca trng vecter

    chuyn ng dk, trng phn on cng sk, v trng phn on i tng (hay

    video) zk. Dng lut Bayes ta c:

    ( ) ( )( )1 11 1 1 1, , , ,

    , , , ,, ,

    k k k k kk k k k k k

    k k k

    p d s g g gp d s z g g g

    p g g g +

    + +

    = (2.37)

    M hnh mng Bayes th hin s tng tc gia 1 1, , , , ,k k k k k kd s z g g g +

    gk

    sk

    dk zk

    gk-1, gk+1

    Hnh 2.1 M hnh mng Bayes cho bi ton phn on video

    2.3 Bm mc tiu theo quy trnh ng thi. Trong phn ny cp h thng gim st mc tiu 3D nh hnh 2.2 H thng gim

    st mc tiu, mc tiu theo di l ngi di chuyn trc ng knh camera, thu nh,

    lu thnh file .avi v a vo h thng nhn dng v theo vt s dng tng mch lc

    Kalman bm theo i tng cn theo di.

    Hnh 2.2. H thng bm mc tiu

    M t h thng:

    S h thng gim st mc tiu hnh 2.2. H thng gm tn hiu vo v b phn

    pht hin, bm mc tiu v a ra kt qu hin th.

  • 14

    Hnh 2.3. S nhn dng nh

    B lc Kalman c coi nh b c lng trng thi h thng, c cu trc lc n

    gin v hi t tt cng vi kh nng lc nhiu cao [9]. M hnh cn c c

    lng d bo c m t bi h phng trnh trng thi :

    xk = Fxk-1 + vk

    zk = Hxk + ek Vector trng thi xk=[x, y, vx , vy], vector o lng zk = [x, y]T, ng vi ta v vn

    tc ca nh i tng trn mt phng nh thi im k. vk, ek l vector nhiu trong

    qu trnh chuyn ng v sai s php o.

    2.4. Kt lun chng Trong chng ny lun vn nu tng v cc bin th ca b lc Kalman ng dng

    thut ton mch lc Kalman trong bi ton bm mc tiu theo phng php phn

    on, bm mc tiu theo quy trnh ng thi. a ra gii php ng dng thut ton

    lc Kalman theo vt i tng, t file video thc hin tng b lc Kalman bm

    theo ngi di chuyn.

  • 15

    CHNG 3: V D MINH HO 3.1. Bi ton bm mc tiu

    3.1.1 t vn . Mt h thng bm mc tiu bng hnh nh l mt tp hp cc bi ton nh.

    u vo ca h thng s l hnh nh thu c ti cc im quan st.

    u ra ca h thng s l thng tin v chuyn ng ca cc i tng c

    gim st

    M hnh khi qut chung cho h thng bm mc tiu.

    Hnh 3.1 H thng bm mc tiu tng qut

    3.1.2 Bi ton pht hin i tng chuyn ng u vo ca bi ton pht hin i tng chuyn ng l cc khung hnh video

    thu c t cc im quan st, theo di. Nh vy c th gii quyt bi ton ny ta

    cn nghin cu mt s c im ca video.

    3.1.2.1 Cc khi nim c bn v video.

    3.1.2.2 Mt s thuc tnh c trng ca video

    3.1.3 Bi ton phn loi i tng

    3.1.3.1 Phn loi da trn hnh dng.

    3.1.3.2 Phn loi da trn chuyn ng.

    3.1.4 Bi ton theo vt i tng

    3.1.4.1 t vn

    u vo ca bi ton theo vt i tng l cc vt i tng, cc c trng ca

    i tng c pht hin thng qua khi x l pht hin i tng, phn loi i

    tng. Nh vy nhim v ca vn theo vt i tng l chnh xc ha s tng

  • 16ng ca cc vt i tng trong cc khung hnh lin tip t d on hng chuyn

    ng ca i tng.

    3.1.4.2 Cc vn gii quyt

    - Theo vt mc tiu da trn m hnh

    - Theo vt mc tiu da trn min.

    - Theo vt mc tiu da tn ng vin

    - Theo vt mc tiu da vo c trng

    * Chnh xc ho i tng tng ng (Object matching):

    * D on chuyn ng

    Nu gii quyt bi ton bm theo mc tiu t hiu qu v tin cy cao, c th ng

    dng trong rt nhiu lnh vc.

    3.2 Chng trnh m phng bm mc tiu

    3.2.1 Qa trnh thu nhn v nhn dng nh M hnh h thng Camera gim st mc tiu:

    Qu trnh ghi hnh c thc hin bng Webcam ca my Laptop thng qua chc nng h tr Image Acquistion ca phn mm matlab v lu li vi dng .avi hoc

    .mat. Sau s dng file ny input cho module nhn dng nh v bm theo vt mc

    tiu c thc hin bng b lc Kalman

    Chng trnh m phng qu trnh nhn dng v bm mc tiu thc hin theo lu

    hnh 3.6.

  • 17

    3.2.2. Bm mc tiu s dng thut ton Kalman Sau khi mc tiu c nhn dng, pht hin chuyn ng t rt trch c trng s

    c thut ton Kalman bm theo vt i tng thc hin theo lu hnh 3.7.

  • 18

    Rt trch c trng

    Kt thc

    Hin th

    N

    Y

    Hnh 3.7 Lu thut ton lc Kalman

    D on

    Tnh li Kalman

    Hiu chnh

    3.2.2.1 Thut ton mch lc Kalman tuyn tnh

    Bc d on:

    $ $ 1k kx F x

    = , (3.1) 1 Tk kP FP F Q = + .

    li Kalman: 1T T

    k k kK P H ( HP H R ) = + . (3.2)

    Bc hiu chnh:

    $ $ $k k kk kx x K ( z H x ) = + , (3.3)

    k k kP ( I K H )P= . 3.2.2.2 Thut ton mch lc Kalman m rng

  • 19 Bc d on:

    $ $ 1k kx x

    = , (3.4) 1k kP P Q = + .

    li Kalman: 1

    k k kK P ( P R ) = + . (3.5)

    Bc hiu chnh:

    $ $ $k k kk kx x K ( z x ) = + , (3.6)

    k k kP ( I K )P= . 3.2.2.3 Thut ton mch lc Unscented Kalman

    Bc d on:

    $ 20

    L ( m )k i k ii

    x W ( X )

    == , (3.7) $ $2

    0

    TL ( c )

    k kk i k i k iiP W ( X ) x ( X ) x

    =

    = . (3.8) Bin i Unscented:

    k i k i( Z ) h(( X ) )= , i = 0,...,2L (3.9) 2

    0k k

    TL ( c )

    k ki k i k iz z iP W ( Z ) z ( Z ) z R

    =

    = + $ $ $ $ , (3.10) $

    $20kk

    TL ( c )

    kki k i k ix z iP W ( X ) x ( X ) z

    =

    = $ $ , (3.11) li Kalman:

    $1

    k k kkk x z z zK P P= $ $ $ . (3.12)

    Bc hiu chnh:

    $ $ kk k k kx x K ( z z ) = + $ , (3.13)

    k k

    Tk k k kz z

    P P K P K= $ $ . (3.14)

    3.3 Kt qu thc nghim M phng mch lc Kalman bm mc tiu. Cc khung nh c ly ngu

    nhin l frame 72, 81, 93, 125 ca mt on video .avi khc nhau.

  • 20

    Frame 72

    Frame 81

    Frame 93

    Frame 125

    Hnh 3.8: Kt qu bm mc tiu

  • 21Gi tr o lng thc t ti v tr i tng c biu din bi mt hnh ch

    nht mu en trong khi mu xanh th hin cho d on v tr ca mc tiu. Ngoi ra

    kch thc ng bao c th hin qua nh xm nn en, bng nh m mu xanh

    bm theo ng bao.

    T hnh 3.5 cho thy mch lc Kalman c th d on v nh hng chnh

    xc cao. hnh ch nht mu xanh (d on) ph hp tng i chng kht vi hnh

    mu en (o lng). Mch lc Kalman c p ng nhanh. iu ny c ngha l khi

    i tng di chuyn th cho php o thay i t ngt.

    Kt qu m phng ca phng php bm mc tiu s dng mch lc Kalman,

    gi tr sai s c lng RMSE c tnh theo cng thc.

    ( )RMSE MSE GT ES= (3.15) 2

    1

    ( )n

    t

    GT EMSEn== (3.16)

    3.4 Kt lun chng

    Bi ton nghin cu mt s k thut pht hin v bm mc tiu, ng thi

    tin hnh x l cho ra kt qu l i tng ang cn theo vt ang v tr no

    nh du. Sau khi xc nh v tr i tng, s tip tc iu khin thit b ti v tr

    mong mun (v tr ca i tng ang theo vt), ng thi quyt nh ra s kin

  • 22

    KT LUN V HNG PHT TRIN 1. Kt lun.

    * V mt l thuyt.

    Lun vn nu ln tng quan v bm mc tiu, cc khi nim lin quan n

    x l hnh nh trong bm mc tiu, phn tch cc loi nhiu trng thi v m hnh nh

    hng n qu trnh theo di mc tiu di chuyn. Cc phng php bm mc tiu

    nh So khp mu, dng quang, Meanshift, Camshift, tr nh nn, lc Particle, c

    lng Kalman. Mi phng php c nhng im mnh v hn ch khc nhau. Tuy

    nhin mch lc Kalman vn l la chn ti u cho qu trnh bm mc tiu xut pht

    t cc u nhc im ca n.

    * V mt thc tin.

    Lun vn a ra hng tip cn ng dng mch lc Kalman trong bi ton

    bm mc tiu c th nh s dng phng php nhn dng hnh nh ca phng php

    tr nh nn, trch chn c trng, s dng thut ton mch lc Kalman bm mc

    tiu chuyn ng. a ra kt qu m phng, nh gi kt qu sai s c lng v o

    c.

    2. Hng pht trin Trong qu trnh thc hin ti, do nhng hn ch v trnh v thi gian

    thc hin ti, chng trnh c xy dng ch l cc thut ton pht hin chuyn

    ng v theo vt mc tiu da vo video. trin khai trong thc t n i hi cn

    phi ci tin hn na. Hy vng trong tng lai, nhng pht trin di y s gip

    ti hon thin hn.

    - Kt hp vic pht hin khun mt vi vic pht hin mt, pht hin hnh dng

    ca con ngi.

    - Xy dng c thut ton ci thin cht lng ca video nh loi tr nhiu,

    loi tr bong v ti u ha cc thut ton tng tc ca chng trnh.

    - Nghin cu mch lc Unscented Kalman phi tuyn cn chnh h thng v

    tinh.