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CHNG 1:
TRNG I HC BCH KHOA H NI
KHOA CNG NGH THNG TIN
*
N
TT NGHIP I HC
NGNH CNG NGH THNG TIN
XY DNG NG DNG PHT HIN MT NGI DA TRN MU DA
Sinh vin thc hin : Nguyn Hoi Sn Lp CNPM - K48
Gio vin hng dn: ThS Lng Mnh B
H ni 5-2008PHIU GIAO NHIM V N TT NGHIP
1. nh hng ti tt nghip
Tm hiu cc phng php pht hin mt ngi da trn c trng v xy dng ng dng pht hin khun mt da trn mu da.2. Cc nhim v c th ca n tt nghip
Tm hiu cc phng php pht hin khun mt da trn c trng.
Nghin cu phng php pht hin mt ngi da trn mu da.
Xy dng ng dng pht hin mt ngi.3. Li cam oan ca sinh vin:
Ti Nguyn Hoi Sn - cam kt n tt nghip l cng trnh nghin cu ca bn thn ti di s hng dn ca Ths. Lng Mnh B.
Cc kt qu nu trong n tt nghip l trung thc, khng phi l sao chp ton vn ca bt k cng trnh no khc.
H Ni, ngy thng nm 2008
Tc gi n tt nghip
Nguyn Hoi Sn4. Xc nhn ca gio vin hng dn v mc hon thnh ca n tt nghip v cho php bo v H Ni, ngy thng nm 2008
Gio vin hng dn
ThS. Lng Mnh BLI NI UGn y, lnh vc nhn dng ang dnh c nhiu s quan tm nghin cu v th nghim nh nhn dng khun mt, nhn dng vn tay, ging ni, mt,... Trong nhn dng khun mt chim mt v tr kh quan trng. Nhn dng khun mt c ng dng trong nhiu lnh vc nh: hnh s (nhn dng ti phm), cc h thng an ton, bo mt (dng xc nhn cc nhn vin ca t chc), v nhiu lnh vc khc na.
Trong nhn dng khun mt, u tin ta phi ly cc khun mt ra mt cch th cng, ri sau em i nhn dng xem l ai. vic nhn dng khun mt c thc hin mt cch t ng, tc l a vo mt bc nh phi xc nh xem trong nh c nhng ai, r rng cn thc hin mt bc trc l pht hin khun mt.
Vic pht hin khun mt cn c ng dng trong m s ngi. Bao nhiu khun mt c pht hin l c by nhiu ngi. Vic m s ngi c ngha trong giao thng (xc nh lu lng ngi qua li trn ng), trong thng mi (xc nh s lng khch hng ra vo siu th),...
Chnh v th m vic nghin cu v pht hin mt ngi l ht sc cn thit. Vi ti Xy dng ng dng pht hin mt ngi da trn mu da em cng t c mt s kt qu nht nh. s l hnh trang gip em rt nhiu trong thi gian hc tp v lm vic sau ny. c th hon thnh c n l nh cng lao to ln ca cc thy c gio trong trng i hc Bch Khoa H Ni ni chung v cc thy c trong khoa Cng ngh Thng tin, b mn Cng ngh phn mm ni ring. Cc thy c tn tnh ging dy, truyn t cho em nhng kin thc, nhng kinh nghim qu bu trong sut 5 nm hc tp v rn luyn ti trng. Xin c gi ti cc thy, cc c li cm n chn thnh nht. Em xin c by t long bit n ca mnh n thy Lng Mnh B - Ging vin b mn Cng ngh phn mm, khoa Cng ngh thng tin, trng i hc Bch Khoa H Ni ht lng gip , hng dn v ch bo tn tnh trong qu trnh em lm n tt nghip.
Em cng xin c gi li cm n ca mnh n thy L Tn Hng cho em mn web cam thc hnh. Cm n anh Mai Anh Tun K47, nh tham kho n ca anh m em c c nhng kin thc ban u, tng quan v lnh vc ny, t c c s thun li, nhanh chng v nh hng tt hn trong qu trnh lm n.
Cui cng, em xin c gi li cm n chn thnh ti gia nh, bn b ng vin, chm sc, ng gp kin v gip em trong qu trnh hc tp, nghin cu v hon thnh n tt nghip.
H Ni, thng 5 nm 2008
Sinh vin: Nguyn Hoi Sn B CC N
Chng 1:
Tng quan v lnh vc pht hin mt ngi.
Trnh by mt s h mu c dng trong pht hin mt ngi. Trnh by mt s phng php pht hin mt ngi da trn c trng khun mt.Chng 2:
Tng quan phng php pht hin mt ngi da trn mu da. Phng php pht hin mu da. Thut ton phn vng trong nh nh phn. Cc tiu ch xc nh vng mt.Chng 3:
Trnh by v cng c ly mt ngi trong nh. Cng c tng hp histogram.Chng 4:
Thit k, xy dng chng trnh pht hin mt ngi. Th nghim chng trnh v nh gi phng php pht hin mt ngi c p dng.MC LC
8DANH MC HNH V
10CHNG 1: TNG QUAN PHT HIN MT NGI
101.1. Tng quan
111.2. Gii thiu v mt s h mu
111.2.1. H mu HSV
141.2.2. H mu HSL
161.2.3. H mu YCrCb
171.3. Mt s phng php pht hin mt ngi da trn c trng v trn mu da
171.3.1. Phng php da trn mu da v thng tin bin ca K. Sandeep v A.N. Rajagopalan
171.3.1.1. Xc nh 1 im c l mu da hay khng
181.3.1.2. Xc nh v tr v kch thc cc vng trong nh mu da (A3)
191.3.1.3. Quyt nh c phi l vng mt hay khng
191.3.1.4. Kt qu th nghim
201.3.1.5. nh gi
211.3.2. Phng php da trn nhiu chng c ca Manoj Seshadrinathan v Jezekiel Ben Arie
211.3.2.1. Xc nh mu da
221.3.2.2. Da trn hnh dng
221.3.2.3. Dng cc b lc Gabor
231.3.2.4. Tng hp cc kt qu
241.3.2.5. Kt qu thc hin
251.3.2.6. nh gi
251.3.3. Phng php s dng khong cch Hausdorff ca Oliver Jesorsky, Klaus J. Kirchberg v Robert W. Frischholz
251.3.3.1. Khong cch Hausdorff
261.3.3.2. K thut pht hin i tng da trn m hnh
271.3.3.3. Qu trnh thc hin pht hin mt ngi
271.3.4. Phng php da trn phn tch b sng (wavelet packet analysis) ca C. Garcia, G. Zikos, G. Tziritas
281.3.4.1. Xc nh cc vng c mu da mt
291.3.4.2. Xc nh cc ng c vin vng mt
301.3.4.3. Phn lp cc ng c vin da vo phn tch b sng
321.3.4.4. Kt qu th nghim
331.3.5. Phng php s dng cc khung sng (wavelet frames) ca C. Garcia, G. Simandiris v G. Tziritas
331.3.5.1. Tng quan
331.3.5.2. Xc nh cc thnh phn trn khun mt (2 mt, mi, ming)
341.3.5.3. M hnh ha khun mt bng mt mu bin i
361.3.5.4. Phn lp ni dung mu
371.3.5.5. Kt qu thc nghim
39CHNG 2: PHT HIN MT NGI DA TRN MU DA
392.1. Ni dung phng php
402.2. Chi tit cc bc
402.2.1. Pht hin mu da
412.2.1.1. Cng thc mu da
2.2.1.2. Histogram..........................................................................................43
442.2.1.3. Kt hp 2 tiu ch
462.2.2. Lc nhiu
472.2.3. Xc nh cc vng trng
482.2.3.1. Thut ton phn vng c bn
542.2.3.2. Thut ton phn vng nng cao
572.2.4. Phn loi cc vng trng
61CHNG 3: CC CNG C C XY DNG
613.1. Cng c ly khun mt
613.1.1. Mc ch
613.1.2. Cc chc nng
623.1.3. Giao din
633.1.4. Chi tit cc chc nng
633.1.4.1. Ly khun mt t file nh
653.1.4.2. Ly khun mt t file phim
663.2. Cng c tng hp histogram
663.2.1. Mc ch
663.2.2. Cc chc nng
673.2.3. Giao din
683.2.4. Chi tit cc chc nng
70CHNG 4: XY DNG CHNG TRNH V MT S KT QU MINH HA
704.1. Mc ch
704.2. Cc chc nng
714.3. Giao din chng trnh
724.4. Cc k thut x l
724.4.1. Thu hnh t camera
744.4.2. Pht 1 file phim
744.4.2.1. Khi to cho phim
784.4.2.2. Ly frame
804.4.3. Chy bt ng b
824.5. Cc lp c xy dng
824.5.1. YPrPb
824.5.1.1. Mc ch
824.5.1.2. Cc thuc tnh
4.5.1.3. Cc phng thc...............................................................................82
834.5.1.4. V tr
834.5.2. HSV
834.5.2.1. Mc ch
844.5.2.2. Cc thuc tnh
844.5.2.3. Cc phng thc
844.5.2.4. V tr
844.5.3. Vng trng
854.5.3.1. Mc ch
854.5.3.2. Cc thuc tnh
854.5.3.3. Cc phng thc
864.5.3.4. V tr
864.5.4. B lc phn vng
864.5.4.1. Mc ch
864.5.4.2. Cc thuc tnh
864.5.4.3. Cc phng thc
874.5.4.4. V tr
874.5.5. B pht hin mt
874.5.5.1. Mc ch
884.5.5.2. Cc thuc tnh
884.5.5.3. Cc phng thc
894.5.5.4. V tr
894.6. Cc kt qu th nghim
96KT LUN V PHNG HNG PHT TRIN CA TI
97TI LIU THAM KHO
DANH MC HNH V
12Hnh 1.1: M hnh biu din 2 thnh phn mu H,S trong HSV
13Hnh 1.2: M hnh ha h mu HSV
15Hnh 1.3: M hnh h mu HSL
18Hnh 1.4: Mt s mt ngi trong tng hp Histogram ca mu da mt
20Hnh 1.5: Mt s nh kt qu ca phng php
22Hnh 1.6: Biu hi t ca phng php hc RPROP
23Hnh 1.7: Cc hng u khc nhau trong hc du hiu Gabor
24Hnh 1.8: S biu din phng php
25Hnh 1.9: Mt s nh kt qu ca phng php. T tri sang phi: nh nh phn, nh kt qu vi ngng 0,7, nh kt qu vi ngng 0,8
26Hnh 1.10: V d m phng qu trnh nhn ra i tng da trn m hnh
27Hnh 1.11: Qu trnh pht hin mt ngi ca phng php
28Hnh 1.12: S phn b cc im mu da mt trong khng gian HSV v YCrCb
29Hnh 1.13: Minh ha pht hin mu da trong nh
30Hnh 1.14: S phn chia vng ng c vin khun mt trong phng php
32Hnh 1.15: Mt s nh kt qu
34Hnh 1.16: T tri sang phi v t trn xung: nh gc, bng AHH, tn hiu AHH ca mt v tn hiu c ly ra
35Hnh 1.17: Cc tham s ca m hnh khun mt
36Hnh 1.18: Vng xung quanh cc c trng khun mt
38Hnh 1.19: Mt s nh kt qu ca phng php
TOC \h \z \c "hinh chuong 2"
40Hnh 2.1: S khi ca phng php
41Hnh 2.2: V tr ca khu trong phng php
42Hnh 2.3: S phn b cc im mu da trong khng gian YCrCb
42Hnh 2.4: S phn b cc im mu da trong h mu HSV
44Hnh 2.5: Mt s mt ngi c dng trong tng hp histogram mu da
45Hnh 2.6: Mt s kt qu minh ha trong pht hin mu da
46Hnh 2.7: Minh ha pht hin mu da theo tng tiu ch. T tri sang phi: nh vo, nh mu da theo cng thc, nh mu da theo histogram
46Hnh 2.8: V tr ca khu lc nhiu trong phng php
47Hnh 2.9: Minh ha kt qu lc nhiu
48Hnh 2.10: V tr ca khu xc inh vng trng trong phng php
51Hnh 2.11: Thut ton phn vng c bn
52Hnh 2.12: V tr tng i ca 1 im trng so vi vng trng hin ti
52Hnh 2.13: Duyt qua cc im hng xm
53Hnh 2.14: Kt qu minh ha thut ton phn vng c bn
53Hnh 2.15: Minh ha cc lin kt yu gia cc vng trng
54Hnh 2.16: V d v lin kt yu gp phi trong pht hin mt
56Hnh 2.17: Lu thut ton pht hin lin kt yu theo chiu dc
57Hnh 2.18: Kt qu minh ha phn vng nng cao
58Hnh 2.19: V tr ca khu phn loi vng trng trong phng php
59Hnh 2.20: Trng hp pht hin nhm nu ch da vo t l kch thc
59Hnh 2.21: Trng hp pht hin nhm nu khng c cn trn ca t l im trng
60Hnh 2.22: Kt qu phn loi vng trng. T tri sang phi: danh sch vng trng, phn loi theo t l kch thc, phn loi theo c kch thc v t l im trng
62Hnh 3.1: Giao din cng c ly vng mt - u vo nh tnh
63Hnh 3.2: Giao din cng c ly vng mt - u vo file phim
64Hnh 3.3: nh bo li khi m file khng phi l file nh
64Hnh 3.4: Minh ha khoanh vng mt
66Hnh 3.5: Cc iu khin trn form dng cho di chuyn frame trong phim
67Hnh 3.6: Giao din cng c tng hp histogram khi khi ng chng trnh
67Hnh 3.7: Giao din cng c tng hp histogram khi ang son tho 1 histogram
68Hnh 3.8: Giao din khi thm nh vo histogram
TOC \h \z \c "hinh chuong 4"
71Hnh 4.1: Giao din chng trnh vi u vo l file nh
72Hnh 4.2: Giao din chng trnh vi u vo l file phim
72Hnh4.3: Giao din chng trnh vi u vo camera
94Hnh 4.4: Mt s kt qu minh ha pht hin mt ngi
CHNG 1: TNG QUAN PHT HIN MT NGIChng ny trnh by mt s l thuyt c bn trong pht hin mt ngi cng nh mt s phng php pht hin mt ngi. C th, chng ny trnh by cc vn sau:
Cc hng tip cn trong pht hin mt ngi.
Mt s h mu s dng trong pht hin mt ngi; HSV, YCrCb.
Mt s phng php pht hin mt ngi da trn c trng khun mt.1.1. Tng quan
Lnh vc nhn dng ang dnh c nhiu s quan tm trong giai on hin nay. N c ng dng trong cc h thng gim st, an ninh, trong cc my tnh th h mi m con ngi c th tng tc vi my tnh qua c ch hoc li ni, Nhn dng mt ngi l mt trong s . V pht hin mt ngi l mt khu tin x l cho nhn dng mt ngi. tng ca n l: t mt nh chp cnh m ng, ta phi tch ra c cc khun mt trong . Cc khun mt c tch ra s c chuyn cho khu nhn dng.
C nhiu hng tip cn v cc phng php khc nhau trong pht hin mt ngi. Cng c nhiu cch phn chia, gom nhm khc nhau. Sau y la mt s hng tip cn:
Gii php da trn m hnh (top-down model-based approach): trong hng tip cn ny, ngi ta s dng cc m hnh mt ngi khc nhau c t l khc nhau t th nht n tt nht. u tin, nh s c qut bi m hnh c t l th nht. Sau nh c qut vi m hnh c t l tt hn. V cui cng c qut vi m hnh c t l tt nht. ng vi mi t l ch c 1 m hnh khun mt. M 1 m hnh khun mt ng vi 1 gc nhn khun mt c th. Do , nhn chung, phng php ny kh khn trong vic a vo nhiu gc nhn khun mt khc nhau.
Gii php da trn c trng (bottom-up feature-based approach): trong hng tip cn ny, ngi ta s tin hnh tm kim trong nh cc c trng ca khun mt (nh mt, mi, ming,), sau gom nhm chng li vi nhau (da trn mi quan h hnh hc gia chng) to thnh cc ng c vin cho khun mt. Gii php ny c th d dng m rng cho nhiu gc nhn khun mt khc nhau.
Gii php da trn b mt (texture-based approach): trong hng tip cn ny, cc khun mt c pht hin da trn s phn b khng gian cc mc xm ca cc im trong ma trn nh con. Phng php ny kh m rng cho nhiu gc nhn.
Gii php da trn mng nron (neural network approach): trong gii php ny, ngi ta tin hnh hun luyn trn 1 tp nh khun mt v khng phi khun mt. Sau khi hun luyn xong, s c dng vo nhn ra khun mt. nh s c qut bng 1 ca s. Ti mi v tr ca s, ni dung nh c ly ra (c th phi thay i t l (co, gin) v cc nh c hun luyn c kch thc nh nhau v xc nh) v c cho qua b lc mng nron. Nhn chung, phng php ny cho kt qu tt. Tuy nhin tn thi gian hun luyn v su tm mu.
Gii php da trn mu sc (color-based approach): trong gii php ny, u tin ngi ta xc nh cc im trong nh c mu ging mu da mt. Sau , ngi ta khoanh vng cc im li. Cc vng ny c th l khun mt hoc khng. xc nh c phi l mt khng, c th da vo t l kch thc ca vng c tng t t l khun mt khng, hoc da vo t l s im mu da trong hnh ch nht bao vng ,
Gii php da trn chuyn ng (motion-based approach): ngay ci tn ca n cng cho thy gii php ny ch p dng pht hin mt ngi trong phim, khng p dng cho nh tnh. T cc i tng chuyn ng trong nh, da trn mt s tiu ch, ngi ta s xc nh c vng mt. V d nh mt ci lc u, hay nhy mt s l c s pht hin khun mt.
Trong thc t, ngoi nhng phng php n thun i theo mt hng tip cn, th cng c nhng phng php kt hp nhiu hng tip cn cho ra kt qu chnh xc hn, tuy nhin cng phi tr gi v thi gian. Trong n ny, em ch i vo tm hiu cc phng php pht hin mt ngi theo hng da trn c trng v da trn mu sc.
Trong cc phng php pht hin mt ngi, cc tc gi thng s dng nhiu h mu khc nhau. Do , u tin em xin trnh by v mt s h mu c s dng trong cc phng php pht hin mt ngi.1.2. Gii thiu v mt s h mu
Trong pht hin mt ngi, ngi ta thng khng s dng h mu RGB, m thng s dng cc h mu khc nh: HSV, HSL, YCrCb. V nhng h mu ny biu din mu sc ging vi quan im nhn mu sc ca con ngi. Sau y, ta s i vo din t chi tit mt s h mu c th.
1.2.1. H mu HSV
HSV (cn c tn gi khc l HSB) l vit tt ca Hue, Saturation, Value. H mu gm 3 thnh phn H, S, V. Trong h mu ny, cc mu u c biu din da trn 3 thnh phn H, S, V ny.
H l vit tt ca Hue, ngha l mu sc. Thnh phn ny biu din mu sc vn c ca mu nh: , xanh da tri, da cam, N c gi tr t 0 n 360o. Hnh sau minh ha gi tr ca H v mu tng ng:
Hnh 1.1: M hnh biu din 2 thnh phn mu H,S trong HSV trong hnh, cc gi tr ca H c quy v di [0,6), tng ng vi chia cc gc cho 60 . Vic biu din H trong di gi tr no khng thnh vn .
S l vit tt ca Saturation, ngha l bo ha. Ta c th hiu n ging nh khi nim nng trong ha hc, vi dung mi l mu trng v cht tan l mu. S c gi tr nm trong on [0,1]. Khi gi tr ca S ln, lng mu ha trong mu trng nhiu ln, mu s m hn. S=1, mu m nht, chim hon ton mu trng. V ngc li, khi gi tr S nh, lng mu ha trong mu trng t i, mu s nht hn. S=0 tng ng vi khng c mt cht mu no pha trong mu trng, kt qu s khng c mu (cng khng khng nh ngay kt qu l mu trng, v n cn ph thuc vo thnh phn V na, nhng c th khng nh n l mu xm). V d: khi H=0, ta c mu . Nhng khng phi c H=0 l ta c c 1 mu m , n cn ph thuc vo S (tc l ph thuc vo lng mu ha trong mu trng). Khi S nh, ta c mu nht. Khi S ln ta c mu m hn. S=1 mu m nht. Khi S=0, gi tr ca H bng bao nhiu l v ngha, kt qu cng ch l 1 mu trng (gi s V=max).
Thnh phn V l vit tt ca value, n biu th thnh phn sng. V c gi tr nm trong on [0,1]. Bn mc 1 chic o hng, nhng nu bn ng trong bng ti, mi ngi s ch nhn thy chic o mu en. Vai tr ca V l nh vy. Vi 1 gi tr H xc nh, ta c 1 mu xc nh. Vi gi tr S, ta c c m nht cho mu . Nhng ta s khng th cm nhn ng mu vi m nht , nu sng khng chun. Khi V=1 ta mi cm nhn c ng bn cht vn c ca mu. Khi V tng tng ng vi sng tng dn. V=0: khng c nh sng, tt c ch l 1 mu en vi mi H v S. Nh trn, ta ni, khi S=0 th mu kt qu khng ph thuc vo H, nhng cha th ni ngay ta c mu trng v cn ph thuc vo V. Nu V=0 ta c mu en, V=1 ta c mu trng, cn nu 0 nm di khung nh. Hoc c th s dng cc phm mi tn tri, phi trn bn phm. File no khng phi l file nh th s hin th 1 nh thng bo li:
Hnh 3.3: nh bo li khi m file khng phi l file nh
ly khun mt, ta dng chut khoanh vng khun mt:
Hnh 3.4: Minh ha khoanh vng mt
Sau khi khoanh vng ri, ta nhn vo nt Lu khun mt, khun mt s c lu vo file (ui .bmp, nh bitmap 24bpp) mt th mc xc nh. Sau khi nhn nt xong, khung xanh bao khun mt s bin mt, th hin vic lu thnh cng. Thay v nhn nt lu khun mt, ta c th nhn phm Enter trn bn phm thc hin chc nng tng ng. V th mc cha file khun mt, v tr ca n nh sau: khi chn 1 th mc nh duyt, ta s to ra trong th mc mt th mc con c tn l CacKhuonMat. Cc khun mt s c ct trong y, mi khun mt 1 file. Tn cc file khun mt c t theo quy cch: tn file nh cha khun mt + ch s ca khun mt trong file. Trong tng hp histogram, m bo s ngu nhin, khch quan th ta cn trnh s trng lp nh. Trong 1 th mc nh vi s lng nh ln, ta c th khng duyt ht c trong 1 ngy lm vic, m phi thc hin tip vo hm sau. Sang ngy hm sau, khi m li th mc nh , rt kh c th nh c file nh no ta ly khun mt ri, file nh no cha. Ta c th ngh n gii php nh ghi li tn cc file duyt ri, nhng nh vy danh sch c th di, ghi rt mt v mi ln nghi ng 1 file no , li phi i chiu li danh sch di . R rng l khng hp l. Hoc ta c th thc hin cch n gin hn l mi file duyt xong, ta s vo th mc v thc hin chuyn n sang mt th mc khc. V th mc s ch cn li cc file cha duyt. tng l hp l nhng thao tc Cut tng file mt rt vt v khi s lng nhiu. Do , chng trnh a thm chc nng ct file nh, thc hin chuyn file nh duyt sang 1 th mc khc, trnh duyt li. thc hin chc nng ny, sau khi ly ht cc khun mt trong nh ri, ch vic nhn nt Ct nh (hoc nhn phm Delete trn bn phm), file nh ang lm vic s t ng c chuyn n 1 th mc xc nh. Nu lu thnh cng, form s hin th nh khc trong danh sch.V th mc cha cc file nh duyt: khi chn 1 th mc nh, ta s to ra trong th mc 1 th mc con c tn l DaDuyet. y chnh l th mc s cha cc file duyt sau khi nhn nt Ct nh.
3.1.4.2. Ly khun mt t file phim
u tin ta s phi m 1 file phim bng cch nhn nt M file phim . S c 1 hp thoi bt ra cho ta chn file phim. Sau khi file phim c chn, s hin th frame u tin ca phim. Ch s frame c ghi trn thanh tiu ca form. di chuyn qua cc frame, ta cng s dng cc phm mi tn ( v --> nh i vi duyt th mc nh. Tuy nhin chng trnh cng cung cp thm mt b iu khin h tr duyt file phim l nhy n v tr 1 frame xc nh.
Hnh 3.5: Cc iu khin trn form dng cho di chuyn frame trong phimTa nhp ch s frame mun n vo text box, ri nhn nt i, chng trinh s hin th frame c ch s . L do ca vic a ra chc nng ny l: trong 1 file phim thng c rt nhiu frame, hng trm frame. Trong 1 bui lm vic, c th ta khng di chuyn qua ht c cc frame ly cc khun mt. Cng vic c tip tc vo ngy hm sau, nu ch c cc mi tn, ta s phi nhn nhiu ln di chuyn n frame kt thc ca ngy hm qua, v vy chc nng ny c xy dng thun tin trong tnh hung ny (ta c th nhp ch s frame dng ca ngy hm qua, v nhn nt i, lp tc s nhy ngay n v tr dng ca ngy hm qua). lu cc khun mt, ta cng thc hin nh i vi file nh, cng dng chut khoanh vng khun mt, ri nhn nt Lu khun mt hoc nhn phm Enter trn bn phm thc hin lu n. V tr t cc khun mt nh sau: khi ta chn 1 file phim, chng trnh s to 1 th mc trong cng th mc cha file phim c tn l: CacKhuonMat. Cc khun mt c ly ra s c lu trong ny.V ch c 1 file phim, nn khng c chc nng ct file phim nh i vi duyt th mc.3.2. Cng c tng hp histogram
3.2.1. Mc ch
Cng c ny c xy dng tng hp v chun ha histogram t mt tp nh mu da c chun b trc, phc v cho cng tc pht hin mu da sau ny.3.2.2. Cc chc nng
Cng c ny c chc nng ging nh mt b son tho histogram. N cho php: To 1 histogram mi (rng).
M 1 histogram tn ti ( c tng hp mt phn t ln trc, nay m ra tng hp tip).
Thm cc nh vo histogram.
Lu v lu mi histogram.
Chun ha histogram.3.2.3. Giao din
Giao din ca chng trnh nh sau:Giao din khi mi chy chng trnh:
Hnh 3.6: Giao din cng c tng hp histogram khi khi ng chng trnh
Giao din khi ang son tho 1 histogram:
Hnh 3.7: Giao din cng c tng hp histogram khi ang son tho 1 histogram
Pha bn phi l dy cc button thc hin cc chc nng. Ca s trng gia l list box dng hin th danh sch cc file nh duyt qua trong qu trnh tng hp histogram. Dng text bn di ca s cho bit histogram ang xy dng c bao nhiu im nh ri ( l tng s im ca tt c cc file nh duyt qua khi tng hp histogram).3.2.4. Chi tit cc chc nng
to mi 1 histogram, nhn vo nt To mi. Khi , chng trnh s bt hp thoi Save file chn ni cha v t tn file cha histogram. File ny c ui l hir. V bn cht, file ny ch l 1 file text. Dng u tin trong file text l tng s im nh duyt qua. Sau dng ny l mt ma trn lu kt qu tng hp histogram. Cui cng l cc dng lu ng dn n cc ni cha cc file nh duyt ri.Nu ta sn c 1 file histogram ri, by gi mun m ra tng hp tip th nhn vo nt M. Chng trnh s m 1 hp thoi cho ta chn file . thm cc nh vo histogram (duyt qua cc nh khc), ta nhn nt Thm vo. Chng trnh s bt ra 1 hp thoi cho ta chn th mc cha cc file nh. Ti sao li l th mc cha nh m khng phi l cc file nh ring r? V nu c m tng file nh ring r mt s rt mt thi gian v s lng nh ca ta nhiu (trn 200 file). ng thi bc trc (ly cc khun mt) ta t tp trung cc khun mt vo 1 th mc ri.
Sau khi chn xong, chng trnh s thc hin duyt qua cc file nh trong th mc thm vo histogram. Mi file c duyt s c hin ln trn form, trong list box. Nu file c duyt khng phi l file nh s c dng thng bo li ngay bn di dng hin tn file trong list box.
Hnh 3.8: Giao din khi thm nh vo histogramNh ta bit trong file cha histogram c lu c cc th mc duyt ri. Bi v nh ni, khi tng hp histogram cn trnh trng lp file. Do , ta lu li ng dn n cc th mc duyt hn ch s trng lp ny. Khi chn 1 th mc, nu n trng vi 1 trong cc th mc duyt ri, chng trnh s hin th thng bo hi kin xem c mun tip tc tng hp khng? (phi hi v c th vn l th mc , nhng ni dung c th khc ri). Nu cu tr li l KHNG th s b qua, khng lm g c. Nu l C th s tin hnh duyt qua cc file trong th mc a vo histogram.Du * trn list box (gc tri), cho ta bit rng histogram ang m cha c lu. lu histogram ang m, ta nhn vo nt Lu. Sau khi lu xong, du * s mt i. Qu trnh lu l qu trnh ghi li histogram t b nh vo file.Tng hp histogram l thao tc rt tn km v khng phi cht lng tt dn ln, v n cn ph thuc vo nh mu. Do , histogram hin ti tt cho pht hin mu da, nhng sau khi tng hp thm mt s nh mu da na, histogram thu c c th li pht hin mu da km i. iu ny l c th nu cc nh c tng hp tip l khng tt. V th an ton ta c th phi lu bn histogram c ra 1 file khc ri sau mi thm cc nh mi vo. h tr iu ny, chng trnh c a thm chc nng Lu mi lu histogram ang tng hp thnh 1 file khc, khng xa mt kt qu tng hp trc .Histogram c s dng trong pht hin mu da khng phi l histogram vi cc ct l cc s nguyn, m l histogram c chun ha, tc l chia s im trong mi ct cho tng s im nh duyt. Khi , cc ct c gi tr l cc s thc c gi tr trong di [0; 1). thc hin chun ha histogram, nhn vo nt Chun ha trn form. Chng trnh s tin hnh chun ha histogram hin hnh. Histogram c chun ha s c lu trong 1 file c ui l hin. V tr v tn ca file ta s c yu cu nhp vo sau khi nhn Chun ha. Sau khi chun ha xong, s hin hp thoi thng bo thnh cng hoc tht bi.CHNG 4: XY DNG CHNG TRNH V MT S KT QU MINH HAChng ny trnh by v xy dng chng trnh pht hin mt ngi. Bao gm cc vn c th sau:
Mc ch, cc chc nng v giao din chng trnh
Cc k thut x l c ci t trong chng trnh
Cc lp c xy dng
Cc kt qu th nghim pht hin mu da khi chy chng trnh.
4.1. Mc chMc ch ca chng trnh ny l pht hin ra cc mt ngi trong nh hoc trong cc frame (t camera hoc file phim) ri lu chng vo mt ni xc nh phc v cho cc cng tc sau ny (nhn dng hoc hc khun mt,...).4.2. Cc chc nng
Chng trnh h tr pht hin mt ngi trong cc ngun sau:
File nh
File phim
T camera
Vi u vo file nh, chng trnh c cc chc nng:
M mt file nh.
Tm cc khun mt trong nh.
Lu cc khun mt tm c vo 1 th mc xc nh.
Vi u vo file phim, chng trnh c cc chc nng:
M 1 file phim. Cc chc nng cho chy, tm dng v stop file phim. Cho php di chuyn ngu nhin n cc v tr bt k trong phim bng thanh trt ging nh trong cc cng c media nh Window Mediaplayer chng hn.
Cho php va pht phim va tm mt hoc thc hin tm mt trong mt frame c th.
Thc hin lu mt t ng khi pht hin c mt. Chc nng ny c th c bt tt linh hot khi khng mun lu mt.
Trong trng hp u vo l camera (x l online, cc frame c thu v c x l ngay, c d mt ngay), chng trnh c cc chc nng sau:
Dng, chy camera.
Cng nh file phim, n cng cho php va pht camera va tm mt, hoc tm mt trn 1 frame khi camera ang dng. Mt tm c c th c lu t ng vo mt ni xc nh hoc khng lu, ty theo ta thit lp. Trong trng hp nhiu camera, chng trnh cho php chn camera u vo. Camera c chn, hnh nh thu c ca n s c pht ln form v c tm mt.
Trong thut ton pht hin mt ngi c s dng nhiu tham s. Khng c b tham s tt trong mi trng hp. Do , trong cc trng hp khc nhau cn thay i tham s t kt qu tt nht c th. V vy, chng trnh c chc nng cho php thit lp cc tham s , linh hot trong cc trng hp khc nhau. Cc tham s cn thit lp nh: file histogram, cc tham s trong tiu chun mu da, t l khun mt, th mc lu tr cc khun mt tm c,...4.3. Giao din chng trnh
T cc chc nng c yu cu trn, ta tin hnh xy dng giao din chng trnh. V chng trnh c 3 u vo, v vi cc u vo khc nhau, chng trnh c cc chc nng khc nhau ph hp vi tng loi u vo, do giao din cng khc nhau vi tng u vo.Giao din vi u vo file nh:
Hnh 4.1: Giao din chng trnh vi u vo l file nh
Giao din vi u vo file phim:
Hnh 4.2: Giao din chng trnh vi u vo l file phim
Giao din ng vi u vo l camera:
Hnh4.3: Giao din chng trnh vi u vo camera
4.4. Cc k thut x l
4.4.1. Thu hnh t cameraTa s dng th vin sn c l Aforge.Net thc hin thu hnh t camera vo my tnh. Th vin ny ch iu khin c cc camera local, tc l cc camera ni trc tip vi my tnh chy chng trnh ny, ch khng iu khin c cc camera ni vi cc my tnh khc trong mng my tnh (remote camera).
y l th vin vit trn C#. Trong C# c mt khi nim l namespace, n cha mt tp cc lp c lin quan hoc cc namespace khc. AForge l 1 namespace nh vy. N cha nhiu namespace trong n nh: AForge.Imaging, AForge.Video.DirectShow, AForge.Video, dng cho x l nh v video (m file video hoc thu t camera).
Trong th vin ny, thc hin thu hnh t camera, ta s dng th vin AForge.Video.DirectShow. Trong th vin ny c cc lp phc v cho vic pht hin ra cc thit b camera gn vo my tnh, thc hin khi ng v tt cc camera. Cc lp nh sau: FilterInfoCollection: dng pht hin ra cc thit b camera gn vi my tnh. N l mt mng cc i tng FilterInfo, mi i tng ny cha thng tin v 1 thit b camera c pht hin ra.
VideoCaptureDevice: y l lp trc tip iu khin thit b camera, nh cho chy, dng, ly v cc frame. FilterCategory: lp ny nh ngha cc ngun video khc nhau nh t file hay t thit b camera.Trnh t thc hin thu hnh t camera khi s dng th vin ny nh sau:
1. D xt xem c thit b camera c gn vi my tnh khng.
FilterInfoCollection videoDevices =
new FilterInfoCollection( FilterCategory.VideoInputDevice );
Thuc tnh videoDevices.Count cho bit c bao nhiu thit b camera ang c ni vi my tnh. Nu n bng 0 c ngha l khng c thit b no c.2. To 1 i tng VideoCaptureDevice gn vi 1 camera c chn, iu khin n.
VideoCaptureDevice videoSource = new VideoCaptureDevice(
videoDevices[0].MonikerString );
Trong v d ny ta chn iu khin camera s 0. MonikerString l xu c t v thit b camera c chn.3. Cho chy camera.
n gin ch cn gi phng thc Start ca i tng VideoCaptureDevice va to.
videoSource.Start( );
Khi gi phng thc ny, h thng s sinh ra 1 tin trnh ngm. Tin trnh ny s lin tc gi cc frame hnh nh thu c t camera cho chng trnh.4. Dng chy camera.
Thc hin 2 lnh:
videoSource.SignalToStop();
videoSource.WaitForStop();
Sau 2 li gi ny, tin trnh ngm s chm dt hot ng v camera cng dng hot ng.5. Nhn v cc frame khung hnh.
y l iu m chng ta quan tm nht. Khi c c frame chng ta c th lm bt k iu g chng ta mun ln frame . thc hin iu ny, ta cn ng k s kin NewFrame ca i tng VideoCaptureDevice. Thc hin nh sau:
videoSource.NewFrame += new NewFrameEventHandler( video_NewFrame );
private void video_NewFrame( object sender, NewFrameEventArgs
eventArgs )
{
// nhn new frame Bitmap bitmap = (Bitmap)eventArgs.Frame.Clone();
// x l frame nhn c ti y}Kiu delegate NewFrameEventHandler v lp NewFrameEventArgs c khai bo trong th vin AForge.Video (mt phn ca AForge, ni qua trn), ch khng c trong AForge.Video.DirectShow.
4.4.2. Pht 1 file phim
pht mt file phim u tin cn ly ra cc frame, sau pht cc frame tun t ln form, mi frame duy tr trong 1 khong thi gian xc nh.Ta c th dng lp FileVideoSource ca AForge pht file phim. N cng tng t nh thu hnh t camera, c s kin NewFrame, ta s ng k mt hm cho s kin ny. Trong hm x l ca s kin ny, ta s ly v cc frame v x l n. Tuy nhin, n c nhc im l khng truy nhp c ngu nhin ln cc frame, mi ln chy l chy t u, khng tm dng c. V vy ta chuyn sang s dng th vin DirectShow c th truy nhp ngu nhin ln cc frame. Tuy nhin, n cng c nhc im l ta phi t lm qu trnh pht phim, v cc frame do ta ly ra mt cch th cng. Vic thc hin pht phim cng khng phc tp, ta ch cn dng 1 timer vi thuc tnh Interval thch hp, v x l s kin Tick ca n (trong chng trnh, khong thi gian timer l 35ms).Trc khi ly frame trong file phim dng DirectShow, ta phi khi to cho phim . Qu trnh khi to nhm mc ch kim tra xem file a vo c dng video khng (c phi l file phim khng) v ly v cc thng tin ca phim nh kch thc cc frame trong phim.4.4.2.1. Khi to cho phimTa s dng interface IMediaDet (thuc namespace DirectShowLib.DES). T Det l vit tt ca Detector. Qu trnh khi to thc hin cc bc sau: To 1 i tng MediaDet v cho mt tham chiu kiu interface IMediaDet tham chiu n n.
Gn tn file cn pht vo trong i tng .
Kim tra xem trong file c dng video khng (video stream).
Ly v thng tin v dng video nh kch thc thc ca cc frame.
Thc hin c th cc bc nh sau:* To i tng MediaDet:
c th s dng lp MediaDetm cn using namespace: DirectShowLib.DES:using DirectShowLib.DES;Sau to mt th hin ca lp MediaDet bng hm to khng i v cho 1 tham chiu c kiu interface IMediaDet tham chiu nn n:
IMediaDet imd;imd = (IMediaDet)new MediaDet();Mun gii phng i tng MediaDet, thc hin nh sau:
if (imd != null)
{
//huy no
Marshal.ReleaseComObject(imd);
imd = null;
}(lp Marshal nm trong namespace System.Runtime.InteropServices).* t tn file cn pht vo trong i tng:
Gi phng thc put_Filename ca interface IMediaDet:
imd.put_Filename(tenfile);(tenfile l ng dn n file phim mun pht).
* Kim tra xem trong file c dng video khng:
u tin cn ly v s lng dng (stream) c trong file:
int sodong;//so stream trong file
kq = imd.get_OutputStreams(out sodong);Sau , duyt qua cc dng, thc hin truy vn trn cc dng xem c dng no c thng tin video khng: ly thng tin v mt dng th u tin phi a dng tr thnh dng hin hnh:
imd.put_CurrentStream(i);vi i l ch s dng ang xt.
Ly thng tin v dng nh sau:
Guid kieu;kq = imd.get_StreamType(out kieu);Nu kieu == MediaType.Video th l dng video. Lp MediaType nm trong namespace: DirectShowLib.
* Ly v thng tin video (kch thc frame):
Lc ny, dng hin ti ang l dng video, v khi kim tra xem c dng video trong file khng, nu thy c dng video th ta dng lun, khng kim tra na. Thc hin ly thng tin nh sau:
AMMediaType amkieu = new AMMediaType();imd.get_StreamMediaType(amkieu); M ngun y cho khi to phim:private void KhoiTaoPhim(string tenfile)
{
//thuc hien cac buoc can thiet de khoi
//thuc hien tao ra mediadet moi
int kq;
//kiem tra xem da co the hien cua imd chua, neu roi //thi giai phong no truoc
if (imd != null)
{
//huy no
Marshal.ReleaseComObject(imd);
imd = null;
}
//tao lai
imd = (IMediaDet)new MediaDet();
if (imd == null)
{
throw new
Exception("Khng to c i tng
Mediadet");
}
//dua file vua nhan duoc vao doi tuong do
kq = imd.put_Filename(tenfile);
if (kq != 0) //co loi
{
throw new Exception("file phim khng hp
l!");
}
//kiem tra xem no co phai la file video khong
int sodong;//so stream trong file
kq = imd.get_OutputStreams(out sodong);
if (kq != 0)
{
throw new
Exception("Khng m c s stream trong
file!");
}
//chay qua cac dong de xem co dong video khong
int i;
bool co = false; //cho biet co video stream khong
Guid kieu;
for (i = 0; i < sodong; i++)
{
kq = imd.put_CurrentStream(i);
if (kq != 0)
{
throw new
Exception("Khng chn c stream!");
}
//nhan ve kieu media cua dong hien tai
kq = imd.get_StreamType(out kieu);
if (kq != 0)
{
throw new
Exception("Khng ly c kiu
stream!");
}
//kiem tra kieu vua nhan ve
if (kieu == MediaType.Video)
{
co = true;
break;//thoat
}
}
//kiem tra ket qua thu duoc
if (!co)
{
throw new Exception("Trong file khng c
video");
}
//luc nay dang dung o stream video
//nhan ve chieu rong, cao cua cac frame
AMMediaType amkieu = new AMMediaType();
rong_video = cao_video = 0;
kq = imd.get_StreamMediaType(amkieu);
if (kq != 0)
{
throw new
Exception("Khng ly c ni dung
Mediatype!");
}
//kiem tra kieu co chuan khong
if (amkieu.formatType == FormatType.VideoInfo
&& amkieu.formatSize >=Marshal.SizeOf(typeof(VideoInfoHeader)))
{
//chuyen thanh doi tuong lop videoinfoheader
Marshal.PtrToStructure(amkieu.formatPtr, vih);
rong_video = vih.BmiHeader.Width;
cao_video = vih.BmiHeader.Height;
if (cao_video < 0)
cao_video = -cao_video;
//giai phong vung nho
Marshal.FreeCoTaskMem(amkieu.formatPtr);
amkieu.formatPtr = IntPtr.Zero;
}
else
{
throw new Exception("MediaType khng chun!");
}
}4.4.2.2. Ly frame ly frame, ta dng hm GetBitmapBits ca IMediaDet. Hm ny c 5 tham s l: V tr frame. Hm ny coi ton b phim l 1 dng thi gian, l mt dy cc frame lin tc in vo khong thi gian (ch khng phi l 1 tp cc frame ri rc lu trong file), v ta s ly ra 1 frame ti 1 thi im no . V vy n c kiu thc ch khng phi kiu nguyn. y l thi im (tnh theo giy), ch khng phi l ch s frame.
Kch thc ca b m cha frame. Khi con tr ti b m l NULL th tham s ny l u ra cho bit cn bao nhiu b nh cha c frame .
Con tr n b m cha frame.
Chiu rng, cao ca frame ly ra. Nu ta t kch thc ny khc vi kch thc thc ca frame trong file th frame s b co gin cho va vi kch thc a ra .
Hm ny c gi 2 ln. Ln 1 l ly v kch thc b m cn c cha frame:
imd.GetBitmapBits(thoidiem, out size, IntPtr.Zero,
rong_video, cao_video);Sau khi cp pht b nh cho b m, gi hm ny mt ln na d liu thc s vo b m:
kq = imd.GetBitmapBits(thoidiem, out size,
buf, rong_video, cao_video);Ton b m ngun cho ly frame nh sau:private Bitmap LayFrame(double thoidiem)
{
int size;
int kq;
IntPtr buf2;
kq = imd.GetBitmapBits(thoidiem, out size,
IntPtr.Zero, rong_video, cao_video);
if (kq != 0)
{
throw new Exception("Khng c c frame!");
}
//cap phat vung nho
buf2 = IntPtr.Zero;
buf2 = Marshal.AllocHGlobal(size);
if (buf2 == IntPtr.Zero)//khong du bo nho cap phat
{
throw new Exception("Khng cp pht b nh
cho frame!");
}
//lay ve buf
kq = imd.GetBitmapBits(thoidiem, out size,
buf2, rong_video, cao_video);
if (kq != 0)
{
//huy bo nho vua cap phat cho buf
Marshal.FreeHGlobal(buf2);
buf2 = IntPtr.Zero;
throw new Exception("Khng ly c frame!");
}
//tao ra 1 bitmap
//tinh toan stride
int stride;
stride = rong_video * 3;
int sodu;
sodu = stride % 4;
if (sodu != 0)
sodu = 4 - sodu;//phan bu de chia het cho 4
stride += sodu;//cong vao de chia het cho 4
Bitmap bm = new Bitmap(rong_video, cao_video, stride,
System.Drawing.Imaging.PixelFormat.Format24bppRgb,
new IntPtr((int)buf2 + vih.BmiHeader.Size));
//quay lai hinh, vi trong bmp, hang dau la hang cuoi
bm.RotateFlip(RotateFlipType.Rotate180FlipX);
//moi viec thanh cong
//gan lai cho buf
//nhung truoc do phai huy vung nho cua buf
if (buf != IntPtr.Zero)
{
//giai phong vung nho truoc
Marshal.FreeHGlobal(buf);
buf = IntPtr.Zero;
}
buf = buf2;
/*------------------------------------------------------
* neu huy vung buf 2 thi anh se bi hong, vi anh cung dang
* dung vung nho nay
* Viec giu lai con de giai phong sau nay, vi qua bitmap
* khong giai phong duoc vung nho nay
* ----------------------------------------------------*/
return bm;
}4.4.3. Chy bt ng b
Ta cn thc hin chy cng vic tm cc mt ngi trong nh mt cch bt ng b khi u vo l file phim hoc camera. V trong qu trnh tm mt, ta phi cho php ngi dng dng tm mt hay dng pht phim hoc camera bng cch nhn vo button tng ng trn form. Nu ta thc hin ng b th khi form ang x l tm mt, mi s kin nhn nt n n u s khng phn ng, m phim hay camera pht lin tc, tc l ht tm mt trn frame ny s tm mt trong frame khc, do khng c k h no nhy vo dng tm mt hay dng phim, camera. V vy, ta phi chy tm mt mt cch bt ng b. chy bt ng b, tc l to ra 1 tiu trnh mi, ta c nhiu cch. Nhng yu cu ca tiu trnh ny l n phi c kh nng truy nhp ln cc iu khin trn form (button, text box,...) v sau khi tm mt xong, ta phi v ln nh trn form cc khung hnh ch nht mu xanh ti cc v tr khun mt tm c. Vi yu cu ny, ta s s dng lp BackgroundWorker cho chy bt ng b vic tm mt trong frame. Lp ny thuc namespace: System.ComponentModel.i tng ca lp ny c 3 bin s kin phc v cho chy bt ng b l:
DoWork RunWorkerCompleted ProgressChangedS kin DoWork c dng bt u tiu trnh ngm. N c kch hot khi gi phng thc RunWorkerAsync ca i tng BackgroundWorker, v cho chy hm ng k s kin ny. Hm ng k s kin ny phi c mu nh sau:bgwk_DoWork(object sender, DoWorkEventArgs e);
Trong hm ny khng c truy nhp ln cc iu khin trn form. Mu hm ny kiu nh sau:void bgwk_DoWork(object sender, DoWorkEventArgs e)
{
//thuc hien tim mat tren anh dua vao
Bitmap anhvao;
anhvao = (Bitmap)e.Argument;
//chay phuong thuc tim mat cua bo tim mat
e.Result = fdr.TimMat_BDB(anhvao, bgwk, e);
}S kin RunWorkerCompleted c kch hot khi hm ng k trong s kin DoWork thc hin xong. Hm ny chnh l ni a cc kt qu thu c t hm ng k trong s kin DoWork ln form, thc hin truy nhp ln cc iu khin trn form. Cc kt qu c ly ra t thuc tnh Result ca tham s e. Mu hm ng k s kin ny nh sau:
bgwk_RunWorkerCompleted(object sender,
RunWorkerCompletedEventArgs e);
Ni dung trong hm ny kiu nh sau:
void bgwk_RunWorkerCompleted(object sender,
RunWorkerCompletedEventArgs e)
{
if (e.Error != null)//c exeption c qung ra //trong hm chy bt ng b {
MessageBox.Show(e.Error.Message, "Loi");
return;
}
if (e.Cancelled)
{
return;
}
//ly v kt qu t thuc tnh e.Result
//v hin th ln form}S kin ProgressChanged c dng thng bo tin cng vic. N c kch hot khi gi phng thc ReportProgress ca i tng BackgroundWorker. Phng thc ny s c gi trong hm ng k s kin DoWork, sau khi mi cng vic nh hon thnh. Hm ng k s kin ny s nhn v gi tr tin v trnh din ln form. Mu hm ng k s kin ny nh sau:
bgwk_ProgressChanged(object sender,
ProgressChangedEventArgs e);Trong chng trnh khng x l s kin ny.
thc hin cancel cng vic bt ng b ny, ta gi phng thc CancelAsync ca i tng BackGgroundWorker:
bgwk.CancelAsync();ng thi trong mu hm chy bt ng b phi c 2 tham s l: BackgroundWorker v DoWorkEventArgs. Nh trong v d trn, c dng:
e.Result = fdr.TimMat_BDB(anhvao, bgwk, e);Tham s BackgroundWorker dng kim tra xem cng vic ny b cancel cha. Vic kim tra ny c thc hin qua thuc tnh CancellationPending. Nu thuc tnh ny tr v TRUE c ngha l cng vic b cancel. Lc , ta cn dn dp mi th (gii phng ti nguyn), ri thot khi hm. Trc khi thot khi hm phi gn cho thuc tnh Cancel ca tham s DoWorkEventArgs bng TRUE hm x l kt thc bit rng cng vic b cancel, b qua khng lm g c. Cn nu gi tr ca thuc tnh CancellationPending l FALSE c ngha l n khng b cancel, v tip tc bnh thng. Vic kim tra gi tr ca thuc tnh ny c thc hin sau khi xong mt bc cng vic.4.5. Cc lp c xy dng
4.5.1. YPrPb
4.5.1.1. Mc ch
Lp ny c xy dng l chuyn i qua li gia cc h mu YCrCb v RGB, phc v cho thc hin cng thc xc nh mu da trn h mu YCrCb nh trnh by chng 2. Nh ni YPrPb l hnh thc analog ca h mu YCrCb. YPrPb l cc s thc, cn YCrCb l cc s nguyn c ri rc ha t YPrPb. chuyn t RGB sang YPrPb theo chun BT601, ch cn to 1 i tng YPrPb vi hm to c i l cc gi tr r, g, b:
YPrPb yprpb = new YPrPb (r, g, b);
Sau truy vn cc thuc tnh Y, Pr, Pb ly ra cc thnh phn mu tng ng c chuyn i.4.5.1.2. Cc thuc tnh
Lp ny ch c 3 thuc tnh l Y, Pr, Pb, u c kiu l kiu s thc, tng ng vi 3 thnh phn mu ca h YPrPb.4.5.1.3. Cc phng thc
* YPrPb() Hm to khng i. Thc hin gn 0 cho c 3 thuc tnh y, pr, pb.* YPrPb(double gt_y, double gt_pr, double gt_pb) Hm to c i. Thc hin gn cho cc thuc tnh y, pr, pb cc gi tr tng ng: gt_y, gt_pr, gt_pb.* YPrPb(int r, int g, int b,double kb,double kr) Hm to c i. Trong hm to ny thc hin lun vic chuyn i h mu t RGB (vi cc gi tr r, g, b u vo) sang YPrPb v gn li cho cc thuc tnh y, pr, pb. Cc tham s kb, kr l cc tham s trong cng thc chuyn i h mu gia RGB v YPrPb. Gi tr ca cc tham s ny ty thuc vo chun c chn. Do , hm ny c tnh linh ng, cho php chuyn t RGB sang YPrPb theo bt k chun no.
* YPrPb(int r, int g, int b) Hm to c i. Cng tng t nh hm to trn, n thc hin lun vic chuyn i sang h mu YPrPb ri gn li cho cc thuc tnh. N khc ch, chun chuyn i l ngm nh (khc vi hm to trn, chun chuyn i phi nhp vo qua cc gi tr kr, kb). Chun c dng y l: BT601 vi kb=0,114; kr=0,299. Ti sao dng chun ny v trong cng thc mu da ta dng chun ny, nn xy dng hm ny cho thun tin.
* static void TinhPrPb(int r, int g, int b,
out double _pb, out double _pr)
Phng thc tnh (gn vi lp, gi t lp m khng cn to bt k i tng no ca lp).
Dng tnh gi tr pr, pb t gi tr r, g, b a vo theo chun BT601.* void RGB(double kb,double kr,out int r, out int g,
out int b) Dng chuyn i t YPrPb tr li RGB. Cc gi tr kb, kr a vo xc nh chun s dng trong cng thc chuyn i.
* void RGB(out int r, out int g, out int b) Cng tng t nh trn, ch c iu chun tnh l xc nh (khng c kb, kr trong tham s ca hm). l chun BT601.4.5.1.4. V tr
* NameSpace: CDY.CacMoHinhMau* DLL: CacMoHinhMau.dll4.5.2. HSV4.5.2.1. Mc ch
Lp ny c xy dng vi mc ch chuyn i qua li gia 2 h mu RGB v HSV. Cn chuyn i sang h mu HSV l phc v cho cng tc tng hp histogram trn nn HS v tnh trong chng trnh khi xc nh mu da.
chuyn i sang HSV ta ch cn to mt th hin ca lp HSV. Trong hm to truyn vo cc gi tr r, g, b ca h mu RGB:HSV hsv = new HSV (r, g, b);4.5.2.2. Cc thuc tnh
Lp ny cng ch c 3 thuc tnh l H, S, V tng ng vi cc thnh phn ca h mu HSV. Chng u c kiu gi tr l kiu thc: H c gi tr trong on [0; 360), S v V c gi tr trong on [0; 1].4.5.2.3. Cc phng thc
* HSV() Hm to khng i.
Thc hin gn cho cc thuc tnh h, s, v ca lp cc gi tr 0.
* HSV(double gt_h, double gt_s, double gt_v) Hm to c i.
Thc hin gn cho cc thuc tnh h, s, v cc gi tr tng ng gt_h, gt_s, gt_v c truyn vo.
* HSV(int r, int g, int b) Hm to c i.
Trong hm to ny thc hin lun vic chuyn i cc gi tr mu r, g, b trong h mu RGB sang HSV v gn kt qu chuyn i cho cc thuc tnh tng ng.
* static void TinhHS(int r, int g, int b, out int gt_h,
out double gt_s) Phng thc tnh ca lp.
Thc hin tnh cc gi tr H, S trong h mu HSV tng ng vi mu (r, g, b) a vo. N thc hin chuyn i t RGB sang HSV, ri tr v 2 thnh phn H v S trong kt qu chuyn i.
Mc ch xy dng hm ny l thun li trong tng hp histogram v trong xc nh mu da da trn histogram. Nh bit, ta xy dng histogram trn nn HS, tc l ta ch cn tnh 2 thnh phn H, S ny l . Dng hm ny gip ta trnh phi to i, to li i tng HSV vi mi ln tnh, gip tng tc chng trnh.
* void RGB(out int r, out int g, out int b) Thc hin chuyn i ngc li t h mu HSV sang RGB.4.5.2.4. V tr* NameSpace: CDY.CacMoHinhMau* DLL: CacMoHinhMau.dll4.5.3. Vng trng
4.5.3.1. Mc ch
Lp ny c xy dng lu tr cc thng tin v mi vng trng tm c khi duyt nh nh phn, v cung cp cc phng thc thao tc trn n nh: tnh t l kch thc cao/rng, t l s im trng,... Tn ca n trong chng trnh l: VungTrang.4.5.3.2. Cc thuc tnh
Lp c 2 thuc tnh l: int SoDiem: dng lu tr s im trng trong vng. Rectangle ToaDo: dng lu tr ta ca vng trng (l ta ca hnh ch nht bao vng trng.4.5.3.3. Cc phng thc
* VungTrang() Hm to khng i.
Dng to ra 1 vng trng rng. N gn cho thuc tnh SoDiem = 0 v cc kch thc rng, cao trong thuc tnh ToaDo bng 0.
* VungTrang(int x, int y) Hm to c i. Dng to 1 vng trng vi 1 im trng khi u trong vng. im ny c ta (x, y) a vo qua i ca hm.
* ThemDiemTrang(int x, int y) Phng thc ny thc hin thm 1 im trng vo trong vng trng.
Khi thm 1 im trng, thuc tnh SoDiem chc chn s tng ln 1, cn thuc tnh ToaDo c thay i hay khng v thay i thnh phn ta no trong n cn ph thuc vo v tng i ca im vi vng trng. Nu n nm trong khung hnh ch nht bao vng trng th khng cn phi thay i.* double TiLeDiemTrang() Phng thc tr v t l s im trng trong vng so vi tng s im ca vng (chnh l ton b s im nm trong hnh ch nht bao vng v bng rng x cao).* bool TrenNguongTrang(double nguong) Phng thc xc nh xem t l im trng trong vng c ln hn hoc bng 1 gi tr ngng a ra hay khng? Nu ng, n tr v TRUE, nu sai tr v FALSE.
* bool LaTiLeVang(double saiso) y l phng thc xc nh xem t l kch thc ca vng trng c xp x t l vng vi 1 sai s cho php hay khng. u vo ca phng thc l gi tr sai s cho php.
u ra: phng thc tr v TRUE nu t l kch thc ca n xp x t l vng, v tr v FALSE nu sai.
* double TL_CaoRong() Phng thc tnh t s gia chiu cao v chiu rng ca vng trng. N tr v t s ny.4.5.3.4. V tr
* NameSpace: PhatHienMatNguoi* DLL: y l lp xy dng trong chng trnh nn n khng nm trong dll no c.4.5.4. B lc phn vng4.5.4.1. Mc ch
Mc ch xy dng lp ny l xc nh cc vng trng trong nh nh phn. Cc vng trng c xc nh bng thut ton phn vng nng cao. Trong lp ny cng ci t c thut ton phn vng bnh thng. Tn trong chng trnh ca n l: BoLocPhanVung.4.5.4.2. Cc thuc tnh
Lp c 2 thuc tnh l:
int ChieuDaiCua: dng thit lp ngng kch thc ca lin kt yu. ArrayList DSVung: dng tr v danh sch vng trng tm c trong nh. Mi phn t trong danh sch ny l 1 i tng ca lp VungTrang.4.5.4.3. Cc phng thc
* BoLocPhanVung() Hm to khng i. Dng gn cc gi tr mc nh cho cc bin.* unsafe void XDVungNC(byte* p0, int x, int y) Dng xc nh 1 vng trng khi pht hin ra n v thm vng trng ny vo danh sch vng trng.
Thut ton phn vng c p dng l phn vng nng cao, tc l c ci t loi b cc lin kt yu.
p0 l con tr n im u tin trong nh (im c ta (0,0)). x, y l ta ca im bt u vng trng ny.
* unsafe void KT_HangXomNC(byte* p0, int x2, int y2,
VungTrang vt) Dng kim tra xem hng xm ca im ang xt c tha mn iu kin a vo vng trng ang xy dng khng. Khi ta ly 1 im ra khi hng i, ta s phi duyt qua cc hng xm ca n (4 hng xm trn, di, tri, phi). Vi mi hng xm, ta phi xc nh xem c th a n vo vng trng ang xy dng khng. iu kin a vo l: l im trng, cha gn nhn v khng nm trn lin kt yu. Phng thc ny s gip ta thc hin iu .* unsafe void XDVung(byte* p0, int x, int y) Phng thc ny tng t phng thc XDVungNC nh trn. Ch khc ch n b qua vic kim tra iu kin lin kt yu.* unsafe void KT_HangXom(byte* p0, int x2, int y2,
VungTrang vt) Cng nh KT_HangXomNC, khc ch, trong cc iu kin kim tra hng xm khng c iu kin kim tra c thuc lin kt yu khng, ch kim tra xem c phi l im trng v gn nhn cha thi.
Vic gim bt iu kin kim tra s tng tc x l.
* unsafe void XetCuaNgang(byte* p0, int x, int y) Phng thc kim tra lin kt yu theo phng ngang.
Qu trnh thc hin ca phng thc ny nh trnh by trong thut ton xc nh lin kt yu c trnh by trong chng 2.
* unsafe void XetCuaDoc(byte* p0, int x, int y) Phng thc kim tra lin kt yu theo phng thng ng.
* void Apply(Bitmap anh) Phng thc thc hin duyt trn 1 nh nh phn vo, tm ra cc vng trng.
Thut ton phn vng c ci t trong phng thc ny l thut ton phn vng nng cao (loi b lin kt yu). Ni dung thut ton phn vng nng cao c trnh by trong chng 2.4.5.4.4. V tr
* NameSpace: PhatHienMatNguoi* DLL: lp ny c xy dng trong chng trnh nn khng nm trong dll no c.
4.5.5. B pht hin mt
4.5.5.1. Mc ch
Lp ny c xy dng cung cp cc phng thc cho tm ra cc khun mt trong nh. Vic xc nh cc khun mt trong nh c thc hin theo thut ton trnh by trong chng 2. Xy dng thnh 1 lp ring d qun l v c th s dng li.
tm ra cc khun mt vi 1 nh a vo, u tin ta phi to ra 1 th hin ca lp, sau khi gn cc thuc tnh phc v qu trnh pht hin mt l: Histogram v cc tham s trong xc nh mu da v tnh cht khun mt. Sau khi mi th thit lp xong, ta gi phng thc TimMat, phng thc s tr v danh sch cc ta cc khun mt tm kim c.4.5.5.2. Cc thuc tnh
Lp c 2 thuc tnh l:
double[,] Histogram: y l mng cha histogram chun ha c dng trong pht hin mu da. Thuc tnh ny l thuc tnh ch ghi, dng thit lp mng histogram. TS_FD ThamSo_FD: y l 1 cu trc cha cc tham s phc v trong pht hin mt nh: ngng mu da, sai s t l vng,... TS_FD l 1 kiu cu trc c nh ngha nh sau: public struct TS_FD //tham so cua bo phat hien khuon mat
{
public string fileHis;//duong dan den file histogram
public double nguongMauDa;//nguong mau da trong histogram
public double tlTrangMin;//ti le so diem trang nho nhat
public double tlTrangMax;//ti le so diem trang lon nhat
public double saiSoTLV;//+-delta trong ti le vang
public int ktMatMin;//kich thuoc khuon mat nho nhat duoc phep
}Thuc tnh ny cng l thuc tnh ch ghi.4.5.5.3. Cc phng thc
* BoPhatHienMat() Hm to khng i.
Ch n gin thc hin gn NULL cho mng Histogram. V vy, ta cn nh rng, sau khi to ra i tng ca lp th vn cha , m phi gn gi tr c th cho cc thuc tnh, trc khi gi phng thc thc hin tm mt, nu khng s khng tm thy khun mt no c.
* Rectangle[] TimMat(Bitmap anh) Phng thc thc hin duyt qua nh vo tm ra cc khun mt.
Phng thc tr v mt mng cc hnh ch nht bao cc khun mt tm c. Phng thc thc hin theo cc bc trong thut ton c trnh by trong chng 2: pht hin mu da --> lc nhiu --> phn vng --> phn loi vng trng.
* Rectangle[] TimMat_BDB(Bitmap anh, BackgroundWorker
bgwk, DoWorkEventArgs e) Cng l phng thc thc hin tm mt, nhng c thm ch BDB c ngha l bt ng b. Trong phng thc trn, l thc hin ng b, c ngha l phi tm xong khun mt ri mi lm tip cng vic khc. Cn trong phng thc ny, n c s dng chy ngm. bgwk l i tng phc v cho qu trnh chy ngm, cn e l tham s trong qu trnh chy ngm. Trong phng thc tm mt ng b, cc bc trong thut ton tm mt c thc hin lin tip, cn trong phng thc bt ng b ny, sau mi bc ta phi kim tra xem tin trnh ngm ny c b yu cu dng khng, nu c th ta dng ngay cng vic li.
* static bool LaMauDaYCrCb(int y, int cr, int cb) Phng thc xc nh xem 1 mu trong h mu YCrCb c phi l mu da hay khng theo cng thc mu da trn h mu YCrCb c trnh by trong chng 2.
y l phng thc tnh ca lp.4.5.5.4. V tr
* NameSpace: PhatHienMatNguoi* DLL: khng nm trong dll no c v y l lp c xy dng trong chng trnh.4.6. Cc kt qu th nghim
Trong th nghim, ta tng hp histogram xc nh mu da trn hn 200 nh mu da vng. Cc nh ny c ly ra nh cng c ly khun mt trnh by trn. Cc nh phn ln c ly t Internet, mt phn c xin t bn b hoc ca c nhn.
Nh trnh by trn, phng php c da trn mt b cc tham s. Gi tr tt nht ca b tham s c a ra qua thc nghim (khng c gi tr tt cho mi trng hp). Nu ta ly gi tr ngng thp th pht hin c nhiu khun mt hn nhng hu qu l pht hin nhm (nhng ci khng phi l mt nhng li b pht hin l mt) cng tng ln. Qua thc nghim, gi tr ca b tham s thu c l: Sai s t l khun mt so vi t l vng: 0,6. Kch thc khun mt nh nht: 20 pixel.
Ngng histogram xc nh mu da: 0,0002. File histogram c dng l: his090408.hin T l s im mu da trong vng mt: [0,6; 0,9].
Gi tr ngng trong xc nh lin kt yu l 7 im.
Kt qu th nghim trn b tham s ny c cho trong bng sau:
STTTn fileKch thcS khun mtPht hin cPht hin nhmTg thc hin(ms)
1136627.jpg400 x 300110100
2A3021.jpg800 x 60038263440
3asian-businessman-posing-~-dl_k34_0031.jpg300 x 30011040
4asian-father-and-son-~-OFM056.jpg221 x 30011120
5asian-girl-sitting-on-floor-smiling-~-lw_s05_008_04.jpg199 x 30011040
6asian-grandfather-father-and-son-~-OFM059.jpg221 x 300321100
7asian-grandmother-with-two-grandchildren-~-GOY026.jpg300 x 22132170
8asian-grandparents-with-grandson-~-BPH134.jpg300 x 22330080
9asian-male-waiter-at-upscale-restaurant-~-DM060418_074.jpg200 x 30021060
10asian-man-and-woman-in-modern-residence-~-AA045846.jpg300 x 287210110
11asian-man-in-turtleneck-sweater-~-bxp66169.jpg200 x 30011090
12asian-mother-and-daughter-~-OFM060.jpg221 x 30022060
13asian-woman-with-basket-of-dirty-laundry-~-HWK034.jpg300 x 22110160
14boa-12m46855.jpg800 x 600100620
15boy-in-playground-looking-at-camera-people-in-the-background-~-AP03476.jpg300 x 20020040
16china97.jpg520 x 7002211180
17close-up-of-asian-woman-smiling-indoors-~-lw_s05_021_05.jpg300 x 199100100
18close-up-portrait-of-young-asian-man-~-AA043865.jpg298 x 300100100
19DSCN0054.jpg800 x 6001571470
20dsfsg68177.jpg525 x 800100310
21four-young-people-sitting-in-a-park-~-b03717.jpg225 x 30021040
22GirlxinhVN1(1)14522.jpg533 x 800100320
23GirlxinhVN1(6)81399.jpg458 x 336201100
24GirlxinhVN1(7)85157.jpg500 x 37510190
25GirlxinhVN1(9)64436.jpg640 x 480200150
26GirlxinhVN176486.jpg640 x 480100320
27group-of-asian-office-people-looking-at-the-camera-smiling-~-ITF055010.jpg297 x 300500100
28h31592.jpg400 x 543101180
29hanh1.jpg160 x 13010050
30IMG_0679.jpg800 x 600210390
31IMG_0727.jpg800 x 600413490
32IMG_0749.jpg800 x 600623450
33IMG_9341.JPG1600 x 12003111740
34j16978.jpg540 x 304100160
35korean118.jpg700 x 643610310
36laos36.jpg525 x 700205390
37mal56.jpg700 x 477212320
38mongolia28.jpg468 x 700100250
39mongolia55.jpg468 x 700110190
40mongolia56.jpg468 x 700110220
41occidental-man-and-asian-man-shouting-~-u18926904.jpg300 x 20021040
42office-people-smiling-with-laptop-at-desk-~-u19664126.jpg300 x 20031070
43older-asian-woman-talking-on-phone-~-GOY021.jpg221 x 30011240
44P1040390.JPG1600 x 120011101440
45P1040542.JPG1600 x 12001141470
46P1040565.JPG1600 x 12001021700
47P1050894.JPG1600 x 12005151610
48P1060691.JPG1600 x 12001121240
49P1060695.JPG1600 x 12002291370
50P1060775.JPG1280 x 960744700
51P1060778.JPG1600 x 120010671550
52P1060790.JPG1600 x 12002231560
53P1060826.JPG1600 x 12001111650
54P1080010.JPG1600 x 12002211640
55portrait-of-a-teenage-asian-girl-in-a-multi-colored-sweater-as-she-~-RBF4_74.jpg300 x 300100120
56portrait-of-a-young-asian-boy-in-a-light-blue-shirt-as-he-looks-~-RBF4_01.jpg300 x 300110140
57portrait-of-a-young-asian-boy-in-a-red-shirt-as-he-smiles-and-laughs-~-RBF4_02.jpg300 x 30011190
58portrait-of-a-young-asian-woman-in-a-black-coat-with-a-blue-backgound-~-RBF5_64.jpg300 x 30010080
59portrait-of-a-young-asian-woman-in-a-black-shirt-turns-her-head-and-~-RBF5_88.jpg300 x 30010360
60portrait-of-five-people-smiling-~-u13036865.jpg300 x 20054040
61portrait-of-three-young-people-~-u10517981.jpg300 x 24030050
62portrait-of-two-business-people-~-cb0503bdh_0365.jpg200 x 30021070
63portrait-of-two-young-people-~-u17615797.jpg240 x 30022050
64portrait-of-two-young-people-~-u18797712.jpg300 x 24022380
65portrait-of-two-young-people-~-u30393442.jpg300 x 24021040
66senior-asian-businessman-smiling-~-dl_k34_0301.jpg300 x 30011060
67senior-asian-man-~-u31027575.jpg200 x 30011040
68senior-asian-man-giving-senior-asian-woman-a-neck-massage-san-~-pl060231.jpg200 x 30020330
69senior-asian-man-with-newspaper-outdoors-~-DM060811_056.jpg200 x 30010030
70thai60.jpg415 x 600213200
71thai74.jpg397 x 600112180
72three-business-people-with-asian-man-up-front-~-u17659039.jpg200 x 30032050
73thutuong060308_1.jpg146 x 20011020
74tibet16.jpg525 x 700213290
75Tin5%20004.jpg480 x 640210200
76Tin5%20011.jpg640 x 480824250
77Tin5%20021.jpg640 x 480411190
78Tin5%20054.jpg640 x 480322340
79Tin5%20098.jpg640 x 48023111180
80young-asian-female-model-with-light-blue-winter-parka-~-u21658553.jpg250 x 30010040
81young-asian-female-model-with-white-winter-parka-and-woolen-hat-~-u26145533.jpg250 x 30011090
82young-asian-people-wearing-casual-and-sports-clothing-~-u23413817.jpg250 x 30010060
Tng cng244120112
Th nghim trn hn 82 file nh, vi 244 khun mt. Kt qu pht hin c 120 khun mt (50%), pht hin nhm 112 khun mt. Nh vy t l pht hin l rt thp. T l pht hin nhm cng kh cao.Sau y l mt s kt qu minh ha:
Hnh 4.4: Mt s kt qu minh ha pht hin mt ngiPhng php c u im l c th pht hin c nhng khun mt m (nhng vn r mu da). iu ny khng th thc hin c vi cc phng php hc my, v n hc trn cc nh chun. Vic pht hin cc nh m khng c ngha lm trong nhn dng, nhng c ngha trong m s ngi chng hn.
Nhng trng hp khng pht hin c l do nhiu mu da xung quanh lm m rng vng trng ca khun mt (s dnh lu) lm cho tnh cht ca vng trng khng cn tha mn khun mt na, hoc do cc khun mt dnh vo nhau, hoc tay dnh vo mt, hoc do ci trn,... Tm li phng php khng pht hin tt khi c nhiu vng da, ngoi vng mt, c l ra nh: c, tay, chn,... Nh vy, phng php pht hin tt vo ma ng khng pht hin tt vo ma h.KT LUN V PHNG HNG PHT TRIN CA TIPht hin mt ngi l mt lnh vc ang dnh c nhiu s quan tm hin nay. C rt nhiu bi bo, cc cng trnh nghin cu th nghim v lnh vc ny c cng b v c nhng thnh cng nht nh. Pht hin mt ngi l khu tin x l cho khu nhn dng mt ngi, hng ti xy dng mt h thng nhn dng mt ngi t ng. N cn c ng dng vo m s ngi (c ngha trong giao thng, thng mi,...) v nhiu lnh vc khc na.C rt nhiu cc phng php, k thut khc nhau trong pht hin mu da, nh: cc phng php da trn hc my, cc phng php da trn c trng, cc phng php da trn m hnh,... Mi phng php u c nhng u nhc ring ca n, khng c phng php no hon ho c. C phng php pht hin tt trong trng hp ny, nhng li pht hin km trong nhng tnh hung khc. Vi nhng tnh hung khc , li i hi phng php khc ph hp vi n.* Trong n ny, lm c:
Trnh by c mt s phng php pht hin mt ngi da trn c trng. Cc phng php c trnh by mc chi tit va phi, cha chi tit n mc ci t. a ra mt phng php pht hin mt ngi da trn mu da. Trnh by mt cch chi tit, r rng cc bc trong thut ton.
Xy dng c ng dng pht hin mt ngi vi cc u vo: file nh, file phim, camera. ng dng ci t thut ton pht hin mt ngi da trn mu da trn. ng dng c tc pht hin nhanh, c th thc hin trong cc h thng thi gian thc. N c th pht hin c cc khun mt c kch thc khc nhau, hng khc nhau v sng khc nhau.* Nhng iu n cha lm c:
Phng php a ra c k thut c th ni l n gin. V vy m t l pht hin ng khng cao, v cn pht hin nhm nhiu. ng dng c xy dng, ban u mi ch th pht hin mt ngi trn chng tc ngi da vng. Tuy vn c th pht hin trn cc mu da khc (do vng mu da trong khng gian mu l nh gn, cc mu da khc nhau vn c nhng im chung), nhng cht lng khng tt.* Hng pht trin ca n:
a thm mt s k thut khc na vo trong phng php, nng cao tnh chnh xc ca phng php. Cc k tht d kin a vo nh: b lc Gabor. Pht trin ng dng c th pht hin mt ngi trn mi loi da: da en, da trng, da vng, da .TI LIU THAM KHO
[1]. Nhp mn x l nh s - Lng Mnh B, Nguyn Thanh Thy.
[2]. n tt nghip ca Mai Anh Tun K47.
[3]. Human Face Detection in Cluttered Color Images Using Skin Color and Edge Information by K. Sandeep and A.N. Rajagopalan.
[4]. Face Detection by Integration of Evidence by Manoj Seshadrinathan and Jezekiel Ben-Arie.
[5]. Robust Face Detection Using the Hausdor Distance by Oliver Jesorsky, Klaus J. Kirchberg, and Robert W. Frischholz.
[6]. Face Detection in Color Images using Wavelet Packet Analysis by
C. Garcia, G. Zikos, G. Tziritas.
[7].A FEATURE-BASED FACE DETECTOR USING WAVELET FRAMES by C. Garcia, G. Simandiris and G. Tziritas.
[8]. Feature-based human face detection by Kin Choong Yow and Roberto Cipolla.
[9]. Mt s file Wikipedia v cc h mu.
[10]. Cc file ti liu ca th vin AForge.[11]. Th vic MSDN trc tuyn.Begin
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