phát hiện kí tự trong hình Ảnh dùng swt

8/12/2019 Pht Hin K T Trong Hnh nh dng SWT

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I HC QUC GIA TP. HCH MINHTRNG I HC BCH KHOA

KHOA IN-IN TBMN VIN THNG---------------o0o---------------

BO CON MN HC 2PHT HIN K TBNG PHNG PH P BIN I NT CH SWT)

SVTH : Nguyn Tun QuangMSSV : 41002596GVHD : T.S. V Trung Dng

Tp. HCh Minh, thng 6 nm 2014


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I HC QUC GIA TP.HCH MINH CNG HA X HI CHNGHA VIT NAMTRNG I HC BCH KHOA c lpTdoHnh phc.

---------- ----------S: ______ /BKT

Khoa: in in tBMn: Vin Thng

NHIM VN MN HC 21. HV TN : Nguyn Tun Quang MSSV: 410025962. NGNH: IN T- VIN THNG LP : DD10DV05ti: PHT HIN K TBNG PHNG PHP BIN I NT CH(SWT)

3. Nhim v(Yu cu vni dung v sliu ban u):.............................................................................................................................................

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4. Ngy giao nhim vn: ...............................5. Ngy hon thnh nhim v: ...................................6. Hv tn ngi hng dn: Phn hng dn

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Ni dung v yu cu n c thng qua BMn.

Tp.HCM,ngy...thng..nm2013CHNHIM BMN NGI HNG DN CHNH

PHN DNH CHO KHOA, BMN:Ngi duyt (chm s b): .......................n v: ...............................................................Ngy bo v: ....................................................im tng kt: ................................................Ni lu trn: ..............................


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PHN MU

Li ni u

c k ttrong vn bn ngy nay trthnh mt mng ln trong Thgi my tnh (CV: ComputerVision). Nhn vlch spht trin ca c k ttrong vn bn chng ta c ththy rng y l mng ngdng kh mi m. c k ttrong vn bn c to ra nhm gii quyt 2 vn : Phc vsphttrin ca in bo v to ra cc thit bc sch cho ngi m. Nm 1914,Emanuel Goldberg phttrin mt my tnh c thc cc k tv chuyn i chng thnh mt m sin bo chun(telegraph code). Cng thi gian Edmund Fournier d'Albe pht trin Optophone, mt my qut cmtay khi di chuyn trn mt trang in. Thit bny c thto ra ting khi thy chci hoc k ttngng. Trong cui nhng nm cui thp nin 1920 Emanuel Goldberg pht trin mt hthng c gi lMy tnh thng ktm kim slu trtrong vi phim (microfilm) bng cch sdng mt hthngnhn din m quang hc. Nm 1931 ng c cp bng sng chca Hoa Ks1,838,389 cho phtminh ca mnh. Bng sng ch c mua li bi IBM sau .

Ngy nay, cng vi spht trin vt bc ca phn cng my tnh v cng nghin ton c k ttrong vn bn ng gp rt nhiu ng dng thc tin trong i sng hng ngy. Chng ta c thlyv dnh:

- Nhp dliu cho mc chcng vic: sha sch, kim tra hay xc thc ha n, tm sc, han, hchiu

- Xc thc bin sxe.- Khai thc thng tin quan trng trong nhng ti liu bo him.- Ly thng tin tdanh thip v lu v danh b.- Sha sch mt cch nhanh chng nhm m bo vic lu trsch ddng v thun tin hn.

Ta c thkn dn sha sch ln nh Project Gutenberg.- C thtm kim thng tin trong cc bc nh KTS. Rt nhiu ng dng ngy nay c trang b

tnh nng ny nh Neo Reader (trn smartphone), Google Translate- Chuyn i chvit tay bng chin dng trong vic nhp dliu mt cch tnhin v nhanh

chng cho nhng ai khng thch nhp liu bng bn phm.- p dng trong cng nghhtrngi bkhim th.

c k ttrong vn bn v ang l mt thch thc thu ht c rt nhiu sch tcc nh nghincu, nhng nh sn xut thit bin tv cngi dng. Hai nhnh chnh trong c k ttrong vn bnl Pht hin k tv Nhn din k t. n ny nhm mc chtrnh by vPht hin k tcc onvn bn trong mt hnh nh tnhin bng cch sdng mt phin bn nng cao ca chuyn i brngnt ch(SWT: Stroke Width Transformation). ng dng nhn c hnh nh RGB tm kim chtrongv trvmt hnh nh mi nicc on vn bn pht hin c nh du. Do cc tnh nng ca SWT,kt quc thpht hin vn bn khng phn bit kch thc, hng, phng chv ngn ngca n.


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Mc lc

Cc mc chnh bao gm

I. Gii thiu s lc vSWT Trang 6-121.1.Hai nhnh chnh ca c k ttrong vn bn Trang1.2.SWT

II. Gii thiu thut ton SWT Trang 13-162.1.Vn v ginh2.2.Bin i brng nt ch2.3.Loi bmt sdng d2.4.Tm kim k tthch hp2.5.Nhm cc k tthch hp vo mt vng ch

III. Kt quchy thnghim trn Matlab Trang 17-183.1.Giao din3.2.Tng quan3.3.Thnghim

IV. ng dng v nhng mt hn ch Trang 194.1.ng dng4.2.Nhng hn ch

V. Ti liu tham kho Trang 20VI. Li kt Trang 21


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Phn I. Gii thiu s lc vSWT

1.1.Hai nhnh chnh ca c k ttrong vn bn:c k ttrong vn bn trong mt khung cnh thin nhin l mt phn quan trng ca nhiu tc vthgic my tnh (Computer Vision-CV). V d, vic thc hin nhn dng k tquang hc (Optical CharacterRecognition-OCR) cc thut ton c thc ci thin bng cch u tin xc nh cc khu vc ca vnbn trong hnh nh. Pht hin vn bn trong nhng cnh thin nhin l mt lnh vc nghin cu chuynsu v c rt nhiu cch tip cn gii quyt vn ny. Tuy nhin, hu ht cc chng trnhpht hinvn bn OCR hn chngi sdng ngn ngcth, kch thc v hng ca vn bn. Hn na, trongmt cnh sc thin nhin, chng ta c thkhng mun lm cho cc ginh nh vy v hn chcc ktquph hp. C mt scn bng hn chm chng ta p dng v cht lng ca kt qu. Chng ta cnggii hn tm kim trong hnh th cng t thng tin sai/ nhiu (noise) m chng ta gp phi.[1]

Skhc nhau c bn gia OCR (Nhn din k tQuang hc) v Pht hin k t

OCR Pht hin k tNhn din chtrong cc hnh nh c tcc bnscan, fax v chi tit d c t v nhim vl cc cc k t.c ng dng trong vic nhp d liu hay lythng tin thnh nh

Pht hin k thay vng k tc trong cc nh tnhin, c thl nh chp quang nh vi rt nhiucc chi tit d tha nh hoa l, bng hiuNhimvchnh l chra vng k t.c ng dng trong vic pht hin vng k t, t ta sdng cc thut ton thch hp xkvng k t

V dvOCR v Pht hin k t

OCR

Hnh chp tmt vn bn


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on vn bn c c bng OCR

(Kt quly ttrang webhttp://www.onlineocr.net/)

TD

TD-Thng qua cc thut ton nhm nhn bit cc vng k t
http://www.onlineocr.net/http://www.onlineocr.net/http://www.onlineocr.net/http://www.onlineocr.net/


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n ny sgii thiu vthut ton SWT v cp chi tit vthut ton cng nh ng dng v hn chca n.

1.2.SWTC rt nhiu thut ton pht hin k tnhng thut ton xut mi nht v tra hiu quvt

tri so vi cc thut ton khc chnh l SWT. SWT thhin svt tri so vi cc thut ton khc chdhiu v tiu tn t ti nguyn phn cng khi thc hin.[2]

c cng bnm 2010 bi 3 tc giBoris Epshtein, Eyal Ofek v Yonatan Wexler. Cng trnh khoa hcny c Thut ton ny cn kh mi mi vi gii xl nh.

SWT l thut ton da trn php bin i vbrng ch. iu ny c ngha l ta c thpht hin cvng k tca cc cc ngn ngkhc nhau mt cch ddng m khng i hi phi cho my hc trcvi lng database ln. V dsau y cho taci nhn chi tit hn.[3]

V d1:

nh ly ttrangwww.gabrielweinberg.com
http://www.gabrielweinberg.com/blog/2011/04/toddler-app-user-interface-guidelines.htmlhttp://www.gabrielweinberg.com/blog/2011/04/toddler-app-user-interface-guidelines.htmlhttp://www.gabrielweinberg.com/blog/2011/04/toddler-app-user-interface-guidelines.htmlhttp://www.gabrielweinberg.com/blog/2011/04/toddler-app-user-interface-guidelines.html


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nh ly ttrangwww.designsngold.com

nh ly ttrangwww.canadianarabcommunity.com
http://www.designsngold.com/japanesepend.htmhttp://www.designsngold.com/japanesepend.htmhttp://www.designsngold.com/japanesepend.htmhttp://www.google.com.vn/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=A4KK3CwqJwWDcM&tbnid=QH1WF0_9-_qjbM:&ved=0CAQQjB0&url=http%3A%2F%2Fwww.canadianarabcommunity.com%2Farabiclanguage.php&ei=BP6UU82-IJLd8AX4l4C4Dg&bvm=bv.68445247,d.dGc&psig=AFQjCNGZrpLFhOgr7RLGzkj939ocojDtqA&ust=1402359677703760http://www.google.com.vn/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=A4KK3CwqJwWDcM&tbnid=QH1WF0_9-_qjbM:&ved=0CAQQjB0&url=http%3A%2F%2Fwww.canadianarabcommunity.com%2Farabiclanguage.php&ei=BP6UU82-IJLd8AX4l4C4Dg&bvm=bv.68445247,d.dGc&psig=AFQjCNGZrpLFhOgr7RLGzkj939ocojDtqA&ust=1402359677703760http://www.google.com.vn/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=A4KK3CwqJwWDcM&tbnid=QH1WF0_9-_qjbM:&ved=0CAQQjB0&url=http%3A%2F%2Fwww.canadianarabcommunity.com%2Farabiclanguage.php&ei=BP6UU82-IJLd8AX4l4C4Dg&bvm=bv.68445247,d.dGc&psig=AFQjCNGZrpLFhOgr7RLGzkj939ocojDtqA&ust=1402359677703760http://www.google.com.vn/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=A4KK3CwqJwWDcM&tbnid=QH1WF0_9-_qjbM:&ved=0CAQQjB0&url=http%3A%2F%2Fwww.canadianarabcommunity.com%2Farabiclanguage.php&ei=BP6UU82-IJLd8AX4l4C4Dg&bvm=bv.68445247,d.dGc&psig=AFQjCNGZrpLFhOgr7RLGzkj939ocojDtqA&ust=1402359677703760http://www.designsngold.com/japanesepend.htm


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TV d1 ta c ththy d l chvit ca ngn ngno i na th cc k tc mtk c im chung l nt chlun c brng thay i nh.

V d2:

Tv dhai ta c ththy cng 1 k tnhng vi font khc nhau scho ra hnh dng khc nhau. Nu thchin vic nhn dng k tny bng cch cho my hc th ta phi c 4 mu trong database nhng nu tasdng SWT th khng cn cho hc trc. iu ny c ngha rt ln v gip chng ta cho thc mtthut ton xl mnh mnhng cng ht sc gn nhv tn t ti nguyn phn cng ca my.

V d3:


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Hnh nh trong thc tc rt nhiu chi tit phnh hoa, l, cnh... nn nu ta p dng lun vic nhndin k tth kt qura srt t. Di y l kt quca vic nhn din k ttrc tip cha qua phpbin i.


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Kt quny c ly ttranghttp://www.free-ocr.com/

E .;.*?a.=@~


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Phn II. Thut ton xl ca SWT

2.1.Vn v ginhHnh nh a vo xl l nhng nh tnhin vi nhiu chi tit d, tri vi nhng trang c qut, faxv danh thip. Phn m phng trong Matlab c thnhn c bt khnh nh ca nh dng JPEG. Kch

thc tiu chun ca hnh nh thnghim l 800x600 (hnh nh ln hnvic chy ng dng slu hnmt cht). Hnh nh khng cn qu tt (v dsc a ra trong phn cc th nghim v kt qu) nhngvn bn trong hnh khng qu m. Ngoi ra, vic nhn din khng phthuc ngn ngca vn bn vhng ca n. Vn bn cong skh khn hnpht hin nhng d sao vn c th.

Vic pht hin vn bn trong mt thc thc thl chmu sng trn nn ti, hoc chmu ti trn nnsng. Nn chng ta sc 2 la chn khi xl nh l Nn trng chen hay Nn en chtrng. Ktqushin thcc k tc pht hin nhm li thnh mt khu vc.

2.2.Bin i brng nt ch(SWT)Phn ny sm tthut ton chuyn i brng nt ch. Thut ton nhn c mt hnh nh RGB v

trvmt hnh nh c cng kch thc. Gm c 3 bc chnh: [4]

- Bin i brng ca nt ch.- Nhm cc im nh vo cc k tc thda trn brng nt ch.- Nhm cc k t vo vng vn bn.Mt nt chtrong hnh nh l mt nhm lin tc c chiu rng gn nh khng i. Mt v dca mtnt chc thhin trong hnh 1 (a). SWT tnh ton cho mi im nh chiu rng ca nt m khnng cha im nh l cao nht.

Hnh 1: Cch thc thc hin ca SWT

(a) Nt chbnh thng, nhng im nh cu to thnh nt ny th m hn sovi nn.


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(b) p l pixel ti bin ca nt, tm theo hng gradient p ta tm c q ti bin i xng.(c) Mi pixel theo tia c gn gi bnhnht ca n v chng ta tm c brng ca nt.

u tin, tt ccc im nh c khi to vi bdy nt .Sau , chng ta tnh ton bn cnh(Edge map) ca hnh nh bng cch sdng thut ton pht hin cnh Canny. Chng ta coi cc cnh nhranh gii nt ch. Nu p l mt im nh cnh, hng gradient dp ca n vung gc vi hng ca ranhgii nt. V vy, bc tip theo l tnh ton hng gp gradient ca cc im nh cnh v chy theo cc tiar = p + n * gp (n> 0) cho n khi chng ta tm thy mt im nh cnh q. Nu hng gradient dqti q lkhong i din vi dp(dq = dp/6) th mi im nh trong cc tia c gn khong cch gia p v qnhbrng nt ch. Mi gi trthnh phn s ca nh SWT u ra tng ng vi nhng pixel trong tp[p,q] nu nh n c gi trthp hn. Tuy nhin, nu mt im nh cnh q khng tm thy hoc dql khngi din vi dp, tia c loi b. thch ng vi chai loi vn bn sng trn nn ti v chmu ti trnnn sng chng ta cn phi p dng cc thut ton hai ln: mt ln vi hng tia dpv mt ln vi -dp.[5]

Sau khi thc bc u u tin m ttrn, im nh trong cc a im phc tp c thkhng gigitrbrng nt ch. V l do , chng ta svt qua cng mi tia khng bloi b, trong mi imnh trong tia snhn c gi trti thiu gia gi trhin ti ca n v gi trtrung bnh tia kcn. (Trongcc thut ton ban u, cc im nh c gn gi trtrung bnh nhng tth nghim trn ta nhn ckt qutt hn khi taly ti thiu).

Hnh 2:

Lp y pixel vi nhng gi trSWT

(a) Pixel mu l mt v dvvic c lp y vi gi trti thiu ca di tia ngang v dc iqua n. Gi trbrng tia chnh xc c cha trong n.

(b) Pixel mu cha gi trti thiu gia di 2 tia. y khng phi l gi trng ca brngnt. Mun chnh xc ta cn phi thng qua bc tip theo (strnh by phn sau).

Hnh trn cho ta thy rng nhng trng hp phc tp nh gc th ta skhng ly c brng chng nh miu tpha trn. Chnh v thnn ta sthng qua nhng tia khng bloi bthm mt lnna, tnh gi trmedian SWT ca m ca tt cpixel v thit lp tt cgi trca nhng tia vi gi trSWTtrn m thnh m.

2.3.Loi bmt sdng tbn brng nt ch(SW-Map)


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ci thin kt qu, ta thm mt bc trong thut ton, m mc ch lci thin tch k t. Cc k ttrong hnh nh kt ni vi nhau nhiu ln v thut ton nhn mt nhm cc k tnh mt thnh phnduy nht. V cc tnh cht ca mt nhm cc k tkhng nht thit phi ph hp vi cc tnh cht camt k tduy nht, cc thnh phn ny c thbbtrong cc giai on tip theo. Khi xem xt cc bcca thut ton, ta nhn thy rng cc thut ton SW trvnhiu dng ri rc kt ni cc chci vi nhau.

Sau khi loi bdng nh vy th nhng k tny khng cn c coi l mt phn ca cc thnh phntng t. V vy, vic thm mt bc m cc thut ton i quami im nh, v nu vng ln cn ca nkhng cha im nh tcc thnh phn ca n, im nh c xa khi cc thnh phn. Kt qutvic thm bc ny sc chng minh trong phn sau.

2.4.Tm kim k tthch hpu ra ca SWT l mt nh m mi gi trpixel c cha di ca nt c xc sut cao nht m n thucv. Bc tip theo l nhm cc im nh vo k tthch hp. Hai pixel ln cn c thc nhm vi nhaunu c chung gi brng nt. iu ny sc thc hin bng u tin nhm pixel vi brng nt tngtv sau p dng mt squy tc phn bit cc k tthch hp. Nhm cc hnh nh sc thchin bng cch sdng mt thut ton kt ni cc phn vi nhau. cho php thay i rng sut nttrong mt k tchng ta scho hai im nh c nhm li vi nhau nu t lSWT ca chng t hn3.0.[6]

By gichng ta phi pht hin cc thnh phn lin kt ging nhk tthch hp bng cch p dng mttp hp cc quy tc kh linh hot. Nhng quy nh nh sau:

- Phngsai ca nt-chiu rng trong mt thnh phn khng phi l qu ln. iu ny gip vi loibtn l trong hnh nh tnhin v tn l thng bnhm ln vi vn bn.

- Tlca mt thnh phn phi nm trong mt phm vi nhca cc gi tr, loi bcc thnhphn di v hp.

- Tlgia ng knh ca cc thnh phn v chiu rng trung bnh ca nt t hnmt ngng c hc (y ta cho gi trl 0.1-10). iu ny cng giploi bcc thnh phn di v hp.

- Cc thnh phn c kch thc qu ln hay qu nhcngsbbqua. iu ny c thc hinbng cch hn chchiu di, chiu rng v sim nh ca cc thnh phn.

- Ngoi nhng quy nh trn, vic thm mt quy tc gip loi bnhiu nhiu. N quy nh rng tlgia sim nh ca cc thnh phn v slng im nh trong khung gii hn ca cc thnhphn nn trong mt phm vi gii hn. iu ny bc bcc thnh phn m tri rng trn mtkhng gian rng ln nhng c mt snhim nh, v cc thnh phn trong bao gm hu htcc khung gii hn ca chng.

Cc ngng sdng ban u chng ta ly tSWT m ttrn v c cp nht mt cht theo tng hnh

ra kt quc cht lng cao nht. Cc thnh phn kt ni cn li c coi l k tthch hp v sctng hp thnh cc vng vn bn.[7]

2.5.Nhm cc k tthch hp vo mt vng chV sc mt vi chci khng c mong i xut hin trong hnh nh nn chng ta scgng nhmcc k tthch hp vo vng vn bn. iu ny lc ra nhiu k tsai-k tthch hp xc nh, v ci thintin cy ca kt quthut ton.


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Mt ln na, chng ta ssdng mt tp nhcc quy tc nhm cc k tli vi nhau thnh cc vngvn bn. Nhng quy nh ny sxem xt cc cp chci nh sau:[8]

- Hai k tthch hp nn c bdy nt tng t. L do l chng ta shn chtlgia chiu rngtrung bnh nt c t hnmt sngng.

- Tlgia chiu cao ca cc chci v gia rng ca cc chci khng c vt qu 2,5.iu ny c quy nh l do chc vit hoa bn cnh chthng.

- Khong cch gia cc chci khng c vt qu ba ln chiu rng ca mt chrng hn.- Chci ca cng mt tc dkin sc mt mu sc tng t, do chng ta so snh cc

mu trung bnh ca cc k tthch hp cho ghp ni.- Mt ln na, vic thm mt quy tc trong hn chslng im nh ca cp chci trong

khung gii hn ca cp.

Khi quyt nh ghp hai chci vi nhau, chng ta c 2 la chn: hoc cchkhng c gn mt khuvc no, hoc mt trong schng c nhm li vi cc chci khc. Nu chai u khng c gn,iu chng ta cn lm l khai bo mt khu vc mi. Nu khng, chng ta cn phi kim tra thm mt ktgi cho cc khu vc khc l hp l. Qua thc hin chng ta nhn thy: mt shp nht l hp l nuslng im nh ca cc k ttrong khu vc v sim nh ca k tthm chia cho kch thc cakhung gii hn ca tt ccc chci kt hp khng c thp hn mt sngng. iu ny sm bokhu vc ca vn bn skhng c kt thc lng lo v sto thnh mt "hp" vn bn. Cch tip cn nyc mt cht khc bit so vi phng php tip cn trong cc thut ton ban u, trong tp hp ccchci li vi nhau thnh chui.[9]

Cui cng, khu vc c t hn3 k tsbloi b. Biu thut ton c thhin trong hnh 3. Victhc hin n giai on tp hp vn bn. Chng ta c ththy qua s khi sau [10]

Hnh 3

S khi ca thut ton.

Hnh nh Phc ha cnh SWTTm k tthch

hp

LcTng hp cc

dng chPht hin ch nh du


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Phn III. Kt quchy thnghim trn Matlab

3.1.Giao din

Hnh 3: Giao din ca SWT detector

Chn Browse dn link n file

Chn Dark-on-Light: khi l chen nn trng

Chon Light-on-Dark: khi l chtrng nn en

3.2.Tng quanng dng SWT Text Detector l mt ng dng c vit ra nhm mc ch xc nh v nh du mtvng trong hnh nh m c thcha ch. ng dng nhn u vo l nh RGB v nhn din c chtrng trn nn en v chen trn nn trng. u ra sl nh c cng kch cvi u vo v nh slni m im nh ca chc nh du. Gi trca mi im nh l sID ca khu vc n thuc v,trong 0 c ngha l nkhng thuc vbt kkhu vc. Vic ctnh mun thhin cc chci trongtng khu vc, v khng chl khung gii hn ca khu vc (trong cc hnh mu) l xem hiu qucathut ton tt hn.


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Vic thc hin cc ng dng gm cc thnh phn nh c tho lun trong phn trc:

- Chiu rng nt chuyn i: pht hin cnh v tnh ton chiu rng nt.- Loi bdng lc long khi bn SW.- Tm k tthch hp: tm kim cc thnh phn kt ni v pht hin cc thnh phn vi cc c

im ca mt k t.- Phn nhm cc chci vo vng vn bn.

3.3.Thnghim

Hnh 4

(a) nh gc chen nn trng(b) nh sau khi thc hin bin i SWT

Hnh 5

(a) nh gc chtrng trn nn en.(b) nh sau khi thc hin bin i SWT


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Phn IV. ng dng v nhng hn ch

4.1.ng dngThut ton SWT c thnhn dng c vng k t, iu ny c ngha rt ln cho cng on OCR. Nuchng ta nhn din c vng k ttt th kt quOCR ra st cht lng cao hn. Khng chp dng

cho OCR m chng ta c thmrng ng dng ca SWT cho vic nhn din phv tiu nhngmu phim qung co. Khi bit c ul mu phim qung co ta c thloi bc gip ngi dngkhng phi coi nhng on qung co m mnh khng thch.

4.2.Nhng hn ch- Thut ton ny thch hp cho nhng chc brng nt kh bng nhau, nu nh nt chkhng

ng u nh mt sfont chcch iu th vic pht hin k tskh khn hn.- Khi thc hin trn nh c kch thc ln slm chng ta mt nhiu thi gian hn. nhng

mu thnghim trong n ny kch thc chun l 600x800.


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Phn V. Ti liu tham kho

[1] Detecting Text in Natural Scenes with Stroke Width Transform B.Epshtein, E.Ofek v Y.Wexler




[5] Scene Text Detection via Stroke Width Yao Li and Huchuan Lu21st International Conference on

Pattern Recognition (ICPR 2012) November 11-15, 2012. Tsukuba, Japan





[8] End-to-End Scene Text Recognition Kai Wang, Boris Babenko and Serge BelongieDepartment ofComputer Science and Engineering University of California, San Diego

[9] End-to-End Scene Text Recognition Kai Wang, Boris Babenko and Serge BelongieDepartment of

Computer Science and Engineering University of California, San Diego

[10] End-to-End Scene Text Recognition Kai Wang, Boris Babenko and Serge BelongieDepartment of

Computer Science and Engineering University of California, San Diego


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Phn VI. Li kt

Cm n sgip nhit tnh ca Thy V Trung Dung cng nh cc Thy C gio bmn gip vcung cp cho em nhng kin thc hon thnh n ny.

Trong n ny khng thkhng kn ngi bn nc ngoi ca em l Gili Weiner nhit tnh trao

i thng qua e-mail v gip em hiu r hn nhng khc mc vthut ton ny.

Trong qu trnh lm n chc hn cn c sai thiu vmt kin thc v din gii, em rt cm n sgp qu bu ca Thy V Trung Dng v cc bn sinh vin khc.

Sau khi hon tt n ny em nh hng lun vn tt nghip ca mnh sl vit mt ng dng c thchp hnh v dch cc k tthng qua vic nhn din v c k t.

phát hiện kí tự trong hình Ảnh dùng swt

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