TL/ NGHIEN CL/U DEN TRIEN KHAI - SAN XUAT
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NGHIEN Cini MOT SO KY THOAT SO KHOP VA NHAN DANG, IIHG DONG VAO HE THONG G I A M SAT GIAO THONG TIT DONG
• M M
NGUYIN VAN AN
Sd KH&CN Dien Bien
Hinh anh dong vai tro ra) quan tr9ng trong trao doi thong tin, boi phan Idrn thong tin ma con ngiTdi thu diTtfc thong qua thj giac. Do vay, van de nhan dang trong xuT ly anh, dac biet la so kh6p, phan lo^i, nhan dang doi tiTOng anh chuyen dong dang nhan dUigrc siT quan tam cua nhieu nha nghien culti bdi tmh khoa hpc va Aig dung da dang cua no. He thd'ng giam sat phiTong tien giao thong tiT dong da dn'Oc phat trien va ufhg dung or nhieu nil&c tren the gidl, giup quan ly du'dc cac van de nhU". Phan luong xe, danh gia liAi lUigmg xe, phat hien xe vi pham Luat Giao thong nhlm tang ci/dng giam sat, phat hien va xuT ly k|p thoi cac vi pham, han che tai nan va nang cao y thufc chap hanh Luat Giao thong.
0 ni^6c ta, %}$ phat trien manh me cua cac loai phiTomg tien giao thong diTofng bo dang doi hoi phai day manh cong tac quan ly, vdi nhuhig phiAAig phap va cong cu hien dai. Chmh vi the, viec nghien culki mot so'ky thuat so khdp, bam bdt ddl tufong chuyen dong va nhan dang, nhif phep triif nen, khdp tiAAig quan, trich chon bien anh nhdm xay diriig mo hmh he thong giam sat phiAAig tien giao thong ti^ dong la rat can thie).
Mot SO liy thuat s o MldV. hat bam doi tUVng ^^^ ^^^ sddung tuang quan cheo: Tflcfng quan Chuyen tfong va trich c h o n tfaC trUnO hien cheo hodn toan ed the dfldc md rong cho anh 2D
, vd sfl dung eho van de khdp anh. Cd the xdc dinh Knap anh i •, ^ •, -, i •
dflcfc mau trong anh sfl dung tflcfng quan cheo gifla Ky thuat khdp mau la mot phflcfng phdp phdn ^ ^ b vdi mot mat na thich hcfp. Mat na vd mau eIn ldp m i u sfl dung nguyen dfl lieu anh tho lam vee tor ^^^ ^^^^ ^ ^ . y ^g ^^ ^g ^^^^^ q ^ ^ ^^^
dae trfltig. Mgt mau dfldc dat ra, ed the thdng qua
mdt tap huan luyen, tiep dd dfldc dem so sdnh vdi ^V *hu^t triX dnh theo khung dnh
cae anh con bang each sijf dung mot sd do khoang y^^^ ^j^b ehinh eua ky thuat trfl anh Id de kiem cdch hoac sd do dp gidng. Thdng thfldng, mdt ^^^ 3 dnh cd sai lech vdi nhau khdng, va xac dinh ngfldng dfldc dat ra tren sd do nay d l xdc dinh khi ^^^^ ^. ^^, ^,^ ^^^^ ^^. ^^^^ ^^ ^ , ^- <^^^„ ^^^^
nao thi ta ed dfldc mdt sfl khdp, tfle Id phan ldp , • i-^ 1. •-. ' j - ' - j. ^,. 2. - ^^.. u- u
• • • vung sai lech gifla cua doi tfldng d cac khung hinh thanh cong. . '
trong video.
Khdp dnh sd dung phep doi sdnh pixel-pixel: ^ . , , ™ , . , Phfldng phdp khdp anh ddn gian n h i t la sfl dung '^'^ "'^^ ^^« ^«« ^^^"^ «'^^-- ^ ^ ^ ^ ^ ^ P^^P ^J phep ddi sanh pixel-pixel gifla hai anh. Theo each gian n h i t d l trfl hai khung hinh la tinh gid tri bieu ndy, do do khdp gifla 2 anh (anh eon) ed thd dfldc di§n sfl chenh lech tdng cong v l cfldng do eua tat tinh theo edng thfle: ca eac diem anh tfldng flng tren hai khung hinh:
X y A. X. I ;t=0 y=0
So thang 11.2011 K H O A H O C ^
TL/ NGHIEN CL/U DEN TRIEN KHAI - SAN XUA'T
Trd dnh phdn khoi: Moi kbung hinh dfldc chia thanh cac khdi. Cac khdi tren khung hinh fl dfldc so sdnh vdi khdi tfldng flng tren khung hinh f2. Ve Cd ban, do chenh lech gifla hai khung hinh dfldc tinh nhfl sau:
Phuang phdp biiu do: Y tfldng cua hfldng tiep can nay la cdc anh cd nen khdng ddi va ddi tfldng khdng ddi se cd chenh lech it trong bieu do. Hdn nfla bieu do bat bien vdi viec quay anh va thay ddi it khi thay ddi gdc nhin.
Ky thudt bdt bdm dda vdo phep trif nen vd trich chon dd&ng vien cua doi td0ig chuyen dgng
Trd nen: Phep todn trfl nen cho phep loai bd tat ca cdc ddi tfldng dflng yen trong day frame anh, chi cdn lai cdc ddi tfldng chuyen ddng. Ket qua cua phep trfl nen thfldng chiu anh hfldng eua nhieu do nhieu yeu td nhfl: Cdc dieu kien thdi tidt (gid, dao dpng cdy cd'i, bdng cua ddi tfldng, may mfla...), dnh sdng thay ddi...
a) Tich c^nh Sobcl b)T6dSylS trong c) Gan nhan
/Iiiili 2: lidr tdch dm lifung Bdm doi tUtfng
Bdt hdm doi tUgng dUa vdo sU sai khac giCCa cac frame dnh: Tromg phfldng phdp nay, ta dfla vao ky thuat phdt hipn chuyen dpng tron^^ anh thong qua sai khac gifla ede frame anh liin tiep. Anh sai khac gifla 2 frame dnh lien tiep dflcfc cho Ix/i:
Y){k,p)={\l(k-^l,j)^ hli.I))\\
Viec xfl ly D(k, p) de bdc tach ra cac vung co ddi tfldng chuyen ddng dfldc thtfc hien tiiang tif nhif ky thudt trfl nen. Lfu diem eua phifffn^f phap nay la khdng eIn sfl dung nen nen chat liirfng xii ly khong phu thupc nhieu vdo cdc dieu kien moi trUdng.
Bdm dnh theo phuang phap tiiang quan cheo:
Gia sfl f{x,y) X,y=\,M la mot anh i cap xam),
k n
3
a) Anh gdc b) Anh sau khi bi trU nin Hinh 1: Minh hga kit qud trie nen
Trich chgn dudng vien vd gdn nhdn: De trich chpn cae dfldng vien ta cd the dp dung cdc bp tdch canh len anh trfl nen vd lpc nhieu. Cdc bd tdch canh Sobel, Prewitt, Laplace... ed the sfl dung dfldc trong trfldng hdp nay. Anh sau khi tach canh dfldc gdn nhan de phan biet cdc ddi tfldng can bdm trong day frame anh. Hinh 2 minh hpa cac kdt qua eua cae phep toan nay.
t{x,y) X,y = \,N la anh man khop (hay con goi la
mat na). Tfldng quan cheo gifla anli f \ a mau t dfldc cho bdi:
d},iu,v) = ^[f(x,y)-t(.\-it.v-v)J
Thuqit todn ho trpboc tdch dnh bien sddto, xe mdy
Thudt todn nhi phdn dnh ddu vdo: Nhi phan hod anh dau vdo Id chuyen anh dau vao thanh mot anh den trang. Bang each nay, ta hoan toan co the trich rut ra dfldc cdc thong tin can thiet ve cac ddi tfldng cd mat trong a n h nhii: Dien tich, chu vi, hfldng eua ddi tfldng, toa dp trpng tam, ty le det...
Tren hinh 3 la ket qua phep tdch canh anh dau vac tfl dpng, sfl dung thuat toan Otsu.
'^ K H O A H O C ^ ° ^^^"9 1^-2011
TQ NGHIEN CQU DEN TRIEN KHAI - SAN XUAT
1666 20b 20B 1666
a) Anh dku vao b) Anh sau khi duoc phSn nguong
Hinh 3: Minh hga kit qud dnh sau khi phdn ngudng
Thudt todn tdch cqnh, dd bien: Cdc diem nam tren bien (canh) eua ddi tfldng trong dnh cd tinh chat Id tai dd bien thien dp sdng ldn. Viec tim ra bi§n cua cae ddi tfldng eho phep ta dinh hinh dfldc vung ddi tfldng. Mat khac, bien dd'i tfldng ed nhflng dae tinh b i t bien cho phep ta dinh hinh dfldc vung bien sd dd'i vdi cdc anh xe dfldc chup trong eac dieu kien sang khde nhau. De tdch canh, ta sfl dung cac todn tfl tach canh dfla tren xd'p xi eac toan tfl vi phan todn tfl Sobel, todn tfl Prewitt, todn tfl Canny.
9 ,
a) Anh goc b) Ket qua tach canh Sobel
c) Kit qui tdch canh Prewitt d) K^t qua tach canh Canny
Hinh 4: Minh hoa kit qud tdch biin
Mo td vd trich chpn dac tritng bien dnh Hien nay, ed nhieu each de md ta dfldng bien (chu tuyen) theo eac flng dung khac nhau, ed the kd ddn nhfl phfldng phap bidn ddi Fourier, sfl dung phep bien ddi wavelet, sfl dung phep bien ddi khoang each, khoang each Hausdorff, dung md men bidn... Phfldng phap sfl dung phep bidn ddi Fourier trong mo ta dfldng bien anh ddi tfldng la mpt trong nhiitng each tiep can du manh, eho phep giai quyet nhieu bai todn thfle te.
a) Ddi tflcfng anh; b) Ma chuoi 4-ket ndi; c) Ma chuoi 8-ket ndi
Hinh 5: Minh hga md chuoi bdi cdc kit ndi khdc nhau co°^e,.,,„ „,„ = 12,1,2,2,12,2,3,2,2,3,0,3,0,3,0,0,1,0,1,0,11;
^od^s.,,, n,i = 13,4,3,4,4,5,4,6,7,7,7,0,0,1,1,21
Ihig dung ky thuat so khdn va nhan dang vao he thdng giam sat giao thdng tir ddng
Mo hinh h$ thong gidm sdt giao thong td dgng bdng camera
Th«o dBi ^M' phftn ludng '
thxt ^^
Thu
Dieu IduJn came re.
b^tbifit
Theo dSi, b6nddi
Wpng
^ \ giao thooi
^ ^ a i
N h ^ <1^& thSng hid vi phfin gi&o th3n& luu CSDL.
1
\ Bung
Y
I
Sa do 1: Minh hga md hinh gidm sdt giao thdng tU ddng bdng camera
Mdt he thdng gidm sdt giao thdng tfl ddng bang camera bao gom: Phdn he camera gidm sdt (camera theo ddi phdn luong), camera chup hinh (chup bien sd xe), mang truyen thdng, mdy chu IflU trfl video, p h i n mem xfl ly anh vd CSDL.
Cdc camera gidm sdt se theo ddi vd chup bien sd xe IflU lai vdo phan he thu nhdn anh. Dfla vao dd, phan he theo ddi ddi tfldng se gidm sat dd'i tfldng trong vung quan ly cua camera va kiem tra cdc ddi tfldng dfldc theo ddi. Trfldng hdp dd'i tfldng theo ddi vi pham Luat Giao thdng thi dd'i tfldng dd hi bat bam. He thdng se xfl ly viec nhan dang, IflU hinh anh vi pham cua ddi tfldng vao trong CSDL. Dong thdi, hd thd'ng dieu khien camera de phan loai, xdc dinh hfldng, theo ddi, bat bdm dd'i tfldng dd phuc vu cho qua trinh xfl ly sau nay. Qua trinh boat dpng eua he thd'ng phan luong giao thdng nhfl sau:
So thang 11.2011 jrxj:r'- T .:, -^f
•wm 47
TL/ NGHIEN CL/U DEN TRIEN KHAI - SAN XUAT
H? th&ig phin lu^ng giao th6ng
B$ phat hi^n chi^f^n d^ng
Bo sung th&ng tin v^
d6i ttvpng mdi c ^ bam: toa 36, thdi gian, kisupfauongti^n,..
Nh^n dang tim vi tri xe tfong frame i n h
Cip nhit thfingtin cic doi tuang dangdinpc bim trong
f«pA
B6 dem xe
-Ki^m txa xe thu$c lin n i o
- Theo \ai\i xe, lin dudng, v i Vf ch dim n i o dang xit de ting s6 xe tuong ung
Tinh van t^c tiung binhctjaxe:
Vtb = Quang ducng di duoc/ Thdi gian - Tsihlai vSntoc liungfairh cualoixE chuaxe do
^ lOtUtvantoc Xba doi tupng v i a dem la Uioi Vap doitucng canbam
Sa do 2: Hogt ddng cda he thdng phdn luong giao thdng Ket qud cdi ddt
Kdt qua nay dfldc the hien d ede hinh 6 vd 7.
PniBBe - B B c k | | r o u n d | p h n n niiuonii
Virr
B O ®
# ^
Hinh 7: Kit qud phdn ldn vd tinh todn mat do theo tung ldn xe
Ket ludn
Nghien eflu mpt sd ky thuat so khdp va nhan dang flng dung vdo h$ thdng gidm sat giao thong tfl dpng da dat dfldc mpt sd ket qua: Nghien cilu tdng quan ve xfl ly anh; nghien eflu ve ky thuat bat bam ddi tfldng chuyen dong; nghien eflu ve ky thuat n h a n dang bien sd xe; iing dung va cai ddt thfl nghiem he thdng phan ludng va phat hien sai ludng cua phfldng tien giao thong. Tuy nhien, nghidn eflu nay chfla the xay dflng dfloc mo hinh he thdng giam sdt giao thdng tfl ddng day du, nen vide cai ddt ehi dflng lai d vi$c phat hien xe sai ludng va tinh todn dfldc mat dd ldn xe. Viec lifu trfl thong tin xe vi pham lan dfldng nhfl bien so xe chfla dfldc cai ddt tich hop vao trong he thdng.
Day cung la nhOfng v i n de ddt ra c i n tiep tuc difcfc
nghidn eflu • 'M
Hinh 6: Kit qud phdn tich ddi tugng chuyin ddng ^f^
.ft Hoatdong ^.,,^,
^ K H O A H O C ^ ° ^^^"9 ^^-2011