Program-algorithm complex for image imposition in aircraft vision systems

Transcription

1 Program-algorthm complex for mage mposton n arcraft vson systems А.I. Efmov 1, А.I. Novkov 1 1 Ryazan State Rado Engnerng Unversty, Ryazan, , Russa Abstract One of the most mportant tasks beng solvable on the arcraft board s a task of mposton of real mages and mages syntheszed accordng to the dgtal terran map. Complex of auxlary tasks and actual mposton task should be solved on a real tme bass (wth frequency 25 frames per second) and wth strct requrements to accuracy of the heterogeneous mage mposton. Tradtonal correlaton-extremal methods of mposton ensure a necessary accuracy but requre unacceptably hgh expendtures of computer tme. The paper descrbes an algorthm of mposton based on affne transformatons of the syntheszed mage to the plane of a real vdeo mage and also algorthms for soluton of auxlary tasks. Keywords: preprocessng; skeleton; mage enhancement; affne transformatons; projectve transformaton; mage mposton 1. Introducton Necessty to mprove arcraft flght securty, to ensure safety of landng requres a development of new methods for ntegraton and nterpretaton of nformaton obtaned from onboard techncal vson systems (TVS) of varous spectral ranges and also from navgaton devces and dgtal terran map (DTM) [1,2]. Vdeo nformaton obtaned from TVS together wth the syntheszed mage of terran relef, cartographc and navgaton nformaton obtanng n real tme help the crew to plot and land under condtons of low vsblty. Onboard TVS can contan a televson (TV) camera, nfrared mager, ldar and radar whch form TV, thermal magng (TI) and locaton mages of the underlyng surface respectvely. 2. Object of research Object of the research s a process of mposton of a real televson (TV) mage obtaned from the televson camera nstalled on an arcraft board and a syntheszed mage n onboard TVS. Syntheszed mage s formed nto an onboard calculator accordng to the dgtal terran map. Imposton of real and syntheszed mages n onboard TVS s one of the most mportant and complcated tasks beng solvable nto the onboard computer complex. Issues occurrng under ts soluton are caused by several reasons. One of the man reasons s errors n detecton of current coordnates of an arcraft as a materal pont n the ar space (lattude, longtude and heght h) and also errors n determnaton of arcraft orentaton as an extended object n the space. Errors n measurement of parameters of the yaw, ptch and roll also belong to them. Errors can be n the dgtal terran map (DTM). Also another source of errors can be sensors formng mages. Dfferent nature of real and syntheszed mages s one more reason complcatng soluton of the mage mposton tasks. Postonng errors can be added by geometrcal dstortons appearng on processed mages at stages of the boundary detecton of brghtness jump and formaton of closed crcuts. 3. Methods of research Wdely known correlaton-extremal methods of mage mposton, as practce of ther applcaton shows, ensure enough good qualty of mposton [3]. However, n the present case search of a global extremum of the objectve functon s joned wth formaton of 10 6 angles (sets of 6 numbers - vector coordnates ν x, y, h,,, of navgaton parameters) and, as a consequence, wth unacceptably hgh expendtures of computer tme. There are known approaches to reduce a spatal dmenson due to usage of the extended angle under formaton of the syntheszed mage and applcaton of a pyramd of dfferent-scaled mages for consecutve refnement of a pont of the objectve functon global optmum under the correlaton-extremal approach to mage mposton [4]. Such modernzaton of correlaton-extremal methods of mposton leads to reducton of computaton efforts but does not solve the ssue up the end both regardng tme and accuracy of the task soluton. Lmtng values of errors n determnaton of navgaton parameters set a correspondng parallelepped n the 6-dmensonal space of parameters. Wthn ths parallelepped, a grd wth nodes s formed. A syntheszed mage s constructed by values of the vector of parameters at each node. Ths mage s overlapped onto a real mage; a value of the objectve functon beng a measure of the mposton qualty s calculated and stored. After enumeraton of all nodes the objectve functon global extremum and vector of navgaton parameters ν opt where ths optmum s acheved are found. Alternatve method to mpose mages s reduced to a search of the same objects on a par of heterogeneous mages, ther comparson, calculaton of the geometrcal transformaton of one mage to the plane of other one and mposton of mages for representaton to a plot. Algorthms based on the geometrcal transformaton of the syntheszed mage to the plane of a real one requre less computaton efforts for ther mplementaton than correlaton-extremal methods and provde acceptable qualty of mage mposton. However, these methods are appled only n cases f contours of contnuous presence objects (water objects, roads, large buldngs etc.) are stably dstngushed on the underlyng surface. Besdes, bottleneck of these methods s a search of 3 rd Internatonal conference Informaton Technology and Nanotechnology

2 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov key (correspondng) ponts onto a par of mposed mages by means of whch transformaton of the syntheszed mage s constructed to the plane of a real one. Correctness of selecton of key ponts determnes a degree of precson of mposed mages,.e. qualty of mage mposton [5]. Methods for enhancement of mage mposton by means of projectve transformatons under presence of less nformatve areas on the mage and, as a consequence, presence of ncorrect pars of key ponts are suggested n papers [6,7]. Alternatve and wdely spread method for constructon of a qualtatve projectve transformaton under presence of some subset of ncorrect pars n a set of pars of key ponts s a usage of the algorthm RANSAC [8]. Imposton algorthm consdered below s based on analyss and comparson of contours on a par of mages. Its bass s affne transformatons of the syntheszed mage to the plane of a real vdeo mage. Affne transformatons do not take nto consderaton projectve dstortons whch nevtably appear under aeral photography [9]. Ther advantage s smplcty of mplementaton, low computatonal efforts provdng functonng n real tme and satsfactory qualty of mage mposton. Suggested algorthm holds an ntermedate poston between correlaton-extremal methods of mposton and methods of projectve geometry. Ths algorthm s a certan compromse under condtons when mentoned methods cannot be mplemented n automatc mode wth acceptable accuracy and tme characterstcs. Although mposton of mages s a fnal and very mportant procedure but possblty and qualty of mage mposton sgnfcantly depend on how successfully auxlary tasks are solved. These tasks nclude tasks of detecton of contours on mages, enhancement of mages, dentfcaton of contours and settng of one-to-one correspondence between contours on a par of heterogeneous mages, formaton of a set of pars of key ponts Imposton algorthm on the bass of transformaton n the complex plane For realzaton of the algorthm t s necessary to have contours of contnuous presence objects both on a real mage and on a respondng syntheszed mage. Specfc requrements are mposed on qualty of contours used n the algorthm. They are consdered below. Algorthm s based on an affne transformaton of ponts on the complex plane accordng to formula ( r) ( s) (s) (r) zk znр zk, z x y, where z k a pont on the syntheszed mage contour, z k a result of transformaton to the real mage plane, znр xпр yпр a complex number provdng transformaton of ponts of one mage to the plane of other one. It s requred to fnd a par of correspondng (key) ponts on the frst and second contours n order to determne a complex number z nр. Let s D be some area on the mage wth boundary D. Suggested varant of the algorthm takes ponts belongng to ends of. Such ponts are found for correspondng the area dameters as correspondng ponts..e. M, M arg max M, M 1 2 j M, M j D 1 ( x2 x1; y2 y1 objects both on the real and respondng syntheszed mages. Vectors a ) and a x x; y ) are 1 ( y1 M1 x1, y1 placed n correspondence wth found ponts M 1 x1, y1 and M 2 x2, y2 on the real mage and respondng ponts the syntheszed one. Complex numbers z x x y and z x x y y y1 1 respond these vectors on the complex plane. Complex number z nр executng transformaton of all ponts of the vrtual mage to the plane of the real one s determned accordng to formula zr zr z z s nр. zs zs zs Algorthm for detecton of ponts M 1, M 2 belongng to ends of the dameter s the followng. Let s take a random pont M on the contour, choose a drecton of the contour tracng and a near pont M ~ s found n ths drecton where local maxmum s realzed ~ M, M max M, M j (1) M j D Then pont M ~ s taken as ntal one and here the followng pont s found for t where the local vew maxmum s acheved (1). After full contour tracng n the chosen drecton a global maxmum s separated from a set of local maxmums and, as a consequence, unknown ponts M 1, M 2 are found. Large volume of expermental researches of the algorthm for determnaton of ponts M 1, M 2 belongng to ends of some contour dameter confrm ts correctness. For search of ponts M 1, M 2 belongng to ends of the dameter of a certan contour t s requred that the contour should be closed. Contours of the real mage obtaned as a result of the algorthm for separaton of boundares of brghtness jump can contan breaks. On the bass of nformaton from the dgtal terran map we know a type of the object and n partcular t s clear that contours of ts boundares should be closed. Algorthm for formaton of contours and addtonal processng s descrbed below. The algorthm s amed at enhancement of the contour mage and, n partcular, removal of breaks of small length whch contours should be closed., on 3 rd Internatonal conference Informaton Technology and Nanotechnology

3 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov Qualty of mage mposton by means of the descrbed algorthm depends on qualty of separaton of brghtness jump boundares. As a rule, skeletons obtaned as a result of separaton of brghtness jump boundares contan a great number of short lnes. They sgnfcantly complcate a search of nterested objects and determnaton of one-to-one correspondence between such objects (between object contours) on real and respondng vrtual mages. For elmnaton of these dsadvantages the algorthm of addtonal processng of contour mages has been developed. It allows elmnatng both closed and unclosed lnes of short length. The algorthm s descrbed n [10]. Fg.1 shows the orgnal TV mage, boundares separated usng Canny detector [11] and enhanced contour mage, and also syntheszed mage respondng to the orgnal TV mage correspondngly. а b c d Fg. 1. Images at varous stages of the technologcal chan executon: а orgnal TV mage; b boundares separated usng Canny detector; c mproved contour mage; d syntheszed mage constructed by the dgtal terran map. After achevement of the enhanced mage of boundares (Fg.1c) t s necessary to obtan a descrpton of contours as a connected set of ponts. Ths procedure s realzed as followng: 1) pxels of the btmap black-and-whte mage obtaned as a result of the prevous processng s looked through; 2) f black pxel s found, t s taken as a start of the contour and marked by the current pxel for analyss; teratve executon of steps 3-4 starts. Black pxels prevously ncluded nto content of some contour s removed from consderaton. 3) pxels adjonng the current one are looked through accordng to the order shown n Fgure 2. In the case of detecton of a neghbor n postons 1-8 t s added to the contour and marked as current one; operaton s repeated; 4) f there are no black pxels n postons 1-8, contour tracng s stopped and return to step 1 occurs; 5) f all pxels of the mage are looked through, algorthm operaton completes Х Fg. 2. Order of pont revew under contourng. In practce, there are often cases when contour of the extended object contans nsgnfcant breaks. For ths purpose, operaton of addtonal combnaton s appled to contour descrptons obtaned by the above-mentoned approach f dstance between end ponts (the begnnng and the end) of a certan par of contours does not exceed a threshold value (threshold value s accepted as 7 pxels). Operaton of addtonal combnaton s addton of pxels of one contour to lst of pxels of another contour f above-mentoned condton s met. It allows removng small breaks and ncreasng qualty of followng procedures of mposton. 3 rd Internatonal conference Informaton Technology and Nanotechnology

4 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov As a result, after processng of the whole mage we have a set of connected contours. It s natural and logcal to remove contours of short lengths,.e. contours where a number of pxels s less that the threshold value (expermental researches have determned that for mages havng resoluton pxels, contour length should be more than 120 pxels). Fnally, we obtan connected contours of long length correspondng to extended objects on the orgnal mage. In addton to checkng for exceedng of the mnmum threshold length, we examne satsfacton to a range of addtonal condtons (these values wll be descrbed below n detals): coordnates x, y of the object «center of mass» should be located on some surroundng of even one of objects from the vrtual map, otherwse correspondences are not found for the mentoned object that negatvely nfluences on the fnal result of mage mposton; length d of the contour dameter should be not more than 2/3 of ts length L; wdth w of the contour s not less than 12 pxels. Executon of mentoned condtons guarantee that only contours of extended closed objects whch can be used for followng mposton wll be on mages Automatc dentfcaton of contours and match makng between them on real and vrtual mages Dgtal terran map contans nformaton on object types whch contours are reflected on the syntheszed mage. Ths nformaton allows dentfyng correspondng objects on the syntheszed mage. Contour analog of the real mage may not contan contours of some objects whch, nevertheless, are present on the syntheszed mage. And otherwse contours can be present on the real mage whch contan specfc dstnctons from the correspondng contours on the syntheszed mage. Dstnctons can be explaned both by outdated state of the dgtal terran map and dsadvantages of algorthms of contour separaton at all stages of the real mage processng. At the vsual level, one-to-one correspondence between object contours s determned enough easly. Task to determne such correspondence by a computer n automatc mode s enough complcated. For soluton of the present task we suggest the algorthm based on usage of some numercal characterstcs. They are calculated for each contour on the real and syntheszed mages: - coordnates x, y of the object «center of mass»; - length L of the contour; - length d of the contour dameter; - wdth w of the contour. M r r r s s s j j j, x, y, M x, y, 1, I, j 1 object centers of mass whch contours are selected on real and Let s desgnate J syntheszed mages correspondngly. Here - a number of the object on the real mage and j - a number on the syntheszed one. Coordnates of centers of mass are found as mean values accordng to the correspondng coordnate by all pxels of the contour. Matrx of dstances between centers of mass of the sze I J s constructed for a set of objects on real and vrtual mages,.e. Dstances are located n the Eucldean metrc. M r s r s r s 1, M1 M1, M 2... M1, M J M s s s r r r I, M1 M I, M1... M I, M J Analyss of correspondences between object centers of mass s based on enough really supposton that shft of the object on the syntheszed mage wth regard to the object respondng to t on the real mage does not exceed a certan lmtng value T. So, f n some lne 0 of the dstance table all dstances are longer than ths value then no object on the syntheszed mage corresponds wth the object wth number 0 on the real mage. Correspondngly, f such stuaton has a place n j0 -column then no object on the real mage corresponds wth the object wth number j 0 on the syntheszed mage. Such objects wll not further partcpate n the procedure for determnaton of correspondences between objects. After removal of objects not havng a correspondng object on other mage from the matrx, procedure for determnaton of correspondences between objects begns. Let s I 1, J1 be numbers of resdual objects on real and syntheszed objects correspondngly. For all resdual objects, both on real and vrtual mages the followng s calculated: - lengths Lr, Ls j, 1, I1, j 1, J1 of contours; - lengths d r, d s j, 1, I1, j 1, J1 of dameters;. 3 rd Internatonal conference Informaton Technology and Nanotechnology

5 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov - values of object wdth wr, ws j, 1, I1, j 1, J1. In ths algorthm, a contour length s consdered as a number of pxels n the contour. Area wdth s consdered as a length b of the vector b N 1 N 2 wth ends on the contour n ts average part and orthogonal to the vector a an area dameter. After all numercal characterstcs of all objects are found, a chan of computatonal procedures and comparsons s performed. Sequentally, n the cycle by from 1 to the end of the real object lst, objects are chosen and followng actons are performed for each of them: r s j 1) n the cycle by executon of nequalty M, M T s checked. Objects j 1, j2,..., jk whch ths nequalty s fulflled for, partcpate n the followng comparson, the rest ones not; 2) by each of three parameters L, d, w for - contour on the real mage, the nearest neghbor s searched on the syntheszed mage j L d w j arg mn L, L L,..., L L 1 j j1 j1 j2 j arg mn d, d d,..., d d 2 j2 j arg mn w, w w,..., w w jk jk 3 j1 j2 jk j Nearest neghbor n each of three condtons n (2) should comply wth nequalty L L j L, d d d j, w w w j. Here 1, 3. These nequaltes are based on suppostons that values of each of three parameters for correspondng objects on real and vrtual mages cannot dffer more than 1 per unt. If j j j j, then the decson s made that the object wth number j on the vrtual mage corresponds to the object wth number on the real mage. Even f all values j, j, j are dfferent then we make a decson that the respondng object on the vrtual mage s not found for the object wth number j, j, j on the real mage Results Fg. 3 shows contours of objects selected on real and syntheszed mages after the stage of mage enhancement. (2) a Fg. 3. Contours of objects selected on real (a) and syntheszed (b) mages. b Dstances between each object on the real mage and all objects on the vrtual mages are calculated accordng to the algorthm for determnaton of correspondence on a par of mages. These dstances are shown n Table 1. Object SI-0 (object wth number 0 on the syntheszed mage) should be removed from the procedure for determnaton of correspondence between objects because dstance from t to each of four objects on the real mage s longer than the threshold value T (T=100 was set as a threshold value for ths experment). Analyss of data from Table 1 allows supposng that by 3 rd Internatonal conference Informaton Technology and Nanotechnology

6 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov mnmum crteron of dstances between objects on real and syntheszed mages (Fg.3) there are the followng correspondences: RI 0 SI 1; RI 1 SI 2 ; RI 2 SI 3; RI 3 SI 4. Table 1. Dstances between objects on the real and syntheszed mages. Object RI-0 RI -1 RI -2 RI -3 SI SI SI SI SI SI SI However, control of determned correspondences by other parameters of objects accordng to algorthm (2) leaves only three correspondences for the fnal mposton that are: RI 0 SI 1 ; RI 1 SI 2 ; RI 2 SI 3. Now we can perform the fnal stage of processng mposton of contours of the syntheszed mage on the real TV-mage. Fg.4a shows a result of smple overlappng of the syntheszed mage on the real one. We can see sgnfcant dscrepances between contours whch are expressed by the shft of the syntheszed mage n relaton to the real one and by contour dmensons. Fg. 4b shows a fnal result of mposton performed accordng to the algorthm. At the vsual level, we can estmate qualty of mposton as satsfactory. a) b) Fg. 4. а result of overlappng of real and sunteszed mages, b result of mposton. Imposton of each eghth frame of the vdeo sequence respondng to magery wthn 4 sec of flght has been performed to estmate algorthm effcency. Results of mposton qualty estmaton by 13 pars of real and syntheszed by DTM frames from ths vdeo sequence are shown n Table 2. Imposton qualty estmaton has been performed usng ndex ntroduced n paper [7]. Man dea of the suggested method s the followng. Image s dvded nto square blocks (cells) of the specfed sze, e.g. 100х100 pxels. It provdes a possblty to obtan not only ntegral estmaton of mposton qualty but also local estmatons n each of separated square blocks. In each cell for all nformatve (other than background color) ponts of one of mages, nformatve ponts of other mage locatng n certan square surroundng of sze ( 2k 1) (2k 1) havng ts center n the processed nformatve pont s searched. As a rule, k 1 or k 2. Value k 1 s equal to thckenng of the thn lne n one pxel of the frst contour up to two pxels, and k 2 up to three pxels. Sldng wndow of the chosen sze ( 55 n the consdered experment) s moved along lnes of the mage. As soon as an nformatve pont of the frst mage gets nto the center of ths surroundng then nformatve pxels of the second mage gettng nto ths surroundng and not marked at the prevous stages are searched and marked. After scannng of the whole mage s completed, n each square blocks a number of m marked ponts of the mposed (second) contour s calculated and we found a rato of ths number to the total number of nformatve ponts of the frst contour an ndex of the mposton qualty n -block of the mage and coeffcent mposton qualty. M,.e. m M m. Let s call coeffcent as M 3 rd Internatonal conference Informaton Technology and Nanotechnology an ntegral ndex of the whole contour

7 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov Results of mposton qualty estmaton by 13 pars of real and syntheszed by DTM frames from ths vdeo sequence are shown n Table 2. Wthn processng of the frst frame there was an mposton dsrupton because correspondence between contours on real and respondng syntheszed mages could not be determned. Enhancement of the mposton qualty was not acheved n two frames. Imposton qualty ncreased wthn the range from 24% to 108% n 10 frames. In paper [12] mposton of heterogeneous mages on these 13 frames was performed usng broken-lnear transformatons whch allow takng projectve dstortons nto consderaton. Ths paper acheved hgher ndces of the mage mposton qualty. Technology of the mage mposton descrbed n [12] requres greater computatonal efforts and t has not yet been automatzed up to the end. Table 2. Results of the mage mposton estmaton. Number of a par of frames Index α before mposton Index α after mposton Change of ndex α Absolut. /percent. Expert estmaton of mage mposton Imposton dsrupton / 42.6% enhanced / 70.4% enhanced / 108.2% enhanced / 80.2% enhanced / -29.3% worsened / 29.7% enhanced / -23.0% worsened / 59.0% enhanced / 31.5% enhanced / 36.6% enhanced / 38.7% enhanced / 23.7% enhanced Mean values / 35.4% Algorthm was also examned on real vdeo sequences obtaned from a TV camera consstng of OVS wthn long tme nterval. Fg.5 shows a dagram of qualty estmaton for 900 frames (36 sec flght). Estmaton of mathematcal expectaton of the mposton qualty n the mentoned vdeo sequence was 0.27, estmated varance Research of nfluence of the scene nature on results of the mposton qualty estmaton has been performed. It determned that qualty estmaton of the mposton algorthm results based on transformaton n the complex plane exceeds the ndex before mposton on the same fragments where we can separate and determne correspondence as mnmum between two objects. For the frames where correspondence was not determned, qualty estmaton remans nvarable. 5. Descrpton of the program-algorthm complex Program-algorthm complex of the mage mposton n avaton vson systems whch consttuent s an algorthm for the mage mposton based on transformaton n the complex plane contans the followng man blocks: 1) block for regstraton of mages obtaned from a vson sensor (n the case of program realzaton on a bench frame capture from the vdeo sequence); 2) block for constructon of a vrtual mage by the vrtual terran model; 3) block of pre-processng of real and vrtual mages; 4) block for mposton and removal of geometrcal msmatch of real and vrtual mages between each other; 5) block for vsualzaton of the mposton result. Blocks 2, 3 and 4 are most mportant for the whole complex and complcated from the pont of vew of ther constructon. Constructon of the vrtual terran model s realzed by the separate software module n the developed realzaton of the mage mposton complex. Its man functons are postonng of the vrtual camera accordng to specfed poston coordnates and constructon of the mage by the avalable dgtal map n format sxf. It s possble to receve a frame both n thn lnes and wth overlapped textures. Block of preprocessng realzes auxlary operatons requred for executon of the geometrcal mposton: separaton of boundares, removal of low nformatve lnes, obtanng of connected contours for real mages; removal of lnes of short extenson and obtanng of connected contours for vrtual mages. Qualty of preprocessng greatly determnes effectveness of the followng mposton. Key element of the program-algorthm complex for mage mposton s a block of geometrcal mposton. The algorthm of mposton based on transformaton n the complex plane as enough fast and relable approach s suggested to be appled as one of algorthms for removal of geometrcal msmatch. Hgh-speed performance of the algorthm of mage mposton based on transformaton n the complex plane s the followng: total costs for preprocessng do not exceed 0.3 sec per frame, for procedures of mposton 0.05 sec. Calculatons are performed usng a computer equpped wth processor Intel QM, 3 rd Internatonal conference Informaton Technology and Nanotechnology

8 Image Processng, Geonformaton Technology and Informaton Securty / А.I. Efmov, А.I. Novkov 2.40 GHz, random-access memory 8 Gb, realzaton of algorthms for preprocessng and algorthm for mposton s performed n the C ++ programmng language. Crcut of the program-algorthm complex organzaton s shown n Fg.6. Fg. 5. Dagram of qualty estmaton for the vdeo sequence. Image from OVS Preprocessng and enhancement Processed mage from TVS Imposton mode (algorthm) Imposton Imposton result Vsualzaton Output mage Informaton on locaton and orentaton DTM Data for mposton Data for vsualzaton Fg. 6. Crcut of the program-algorthm complex organzaton for mage mposton. 6. Concluson As t was mentoned before, correlaton-extremal methods of mposton provde the necessary accuracy but requre unacceptably hgh costs of computer tme. Broken-lnear transformatons of the syntheszed mage to the plane of real vdeo mage are vulnerable because of ssues wth search of a set of key pont pars n the automatc mode [9]. Suggested algorthm s a certan compromse between requrements to accuracy of algorthms for mposton of heterogeneous mages and requrements for ther mplementaton n the automatc mode and n real tme. Consdered algorthm can operate under large errors of navgaton parameters only f smlarty of contours of correspondng objects on real and syntheszed mages s saved. Developed algorthm can be appled ndependently for mposton of mages and t can be used n combned schemes wth algorthms of a hgher level for pre-mposton. References [1] Elesna SI. Imposton of mages n correlaton-extreme navgaton systems. Edted by Kostyashkn LN, Nkforov MB. Moscow: Rado Engneerng, 2015; 208 p. [2] Wslter YuV. Avaton systems of enhanced and syntheszed vson: analytcal revew of materals of foregn nformaton sources. State Scentfc Center of the Russon Federaton, State Scentfc and Research Insttute of Avaton Systems (Federal State Untary Enterprse "GosNIIAS"), Scentfc Informaton Centre; Edted by Fedosov EA. M., 2011; 77 p. [3] Bakltsky VK. Correlaton-extreme methods of navgaton and gudance. Tver: Book Club, 2009; 360 p. [4] Babayan PV, Ershov MD. Algorthms for removal of msmatches n the onboard vson system. Vestnk of RSREU 2015; 4(2): [5] Crum WR, Hartkens T, Hll DLG. Non-rgd mage regstraton: theory and practce. The Brtsh Journal of Radology 2014; 77: [6] Goshn EV, Kotov AP, Fursov VA. Two-stage formaton of spatal transformaton for mage mposton. Computer Optcs 2014; 38(4): [7] Efmov AI, Novkov AI. An algorthm for multstage projectve transformaton adjustment for mage supermposton. Computer Optcs 2016; 40(1): DOI: / [8] Hast A, Nysjö J, Marchett A.. Optmal RANSAC Towards a Repeatable Algorthm for Fndng the Optmal Set. Journal of WSCG 2013; 21(1): [9] Gruzman IS, Krchuk VS, Kosykh VP, Peretryagn GI, Spector AA. Dgtal mage processng n nformaton systems. Novosbrsk: Publshng house of NSTU, 2002; 351 p. [10] Novkov AI, Sablna VA, AI Efmov. Image Supermposton Technque n Computer Vson Systems Usng Contour Analyss Methods. 5th Conference on Embedded Computng (MECO) Proceedngs 2016: [11] John Canny. A Computatonal Approach to Edge Detecton. IEEE Transactons on Pattern an Machne Intellgence 1986; PAMI-8(6): [12] Novkov AI, Sablna VA, Nkforov MB. Algorthms for automatc dentfcaton of objects on heterogeneous mages and mage mposton. Collecton of papers of the III Internatonal Conference and Youth School "Informaton Technologes and Nanotechnologes" 2017: rd Internatonal conference Informaton Technology and Nanotechnology