Brain Blood Vessel Map Extraction Using Waveletbased

Transcription

1 03 8th Iraa Coerece o Mache Vso a Image Processg (MVIP) Bra Bloo Vessel Map Extracto Usg aveletbase DSA Fuso Saba Mome Departmet o Electrcal Egeerg, Naaaba Brach, Islamc Aza Uversty, Isaha, Ira. Hosse Pourghassem Departmet o Electrcal Egeerg, Naaaba Brach, Islamc Aza Uversty, Isaha, Ira. h_pourghasem@au.ac.r Abstract Recetly mage uso has promet a applcable roles mecal mage processg. Dgtal subtracto agography (DSA) mage s apple to splay map o bloo vessels. I ths paper, a ew uso algorthm or DSA seral mages base o screte wavelet trasorm coecets s propose. Our algorthm wll be compare or eret wavelet trasorms a actvty crtera or hgh requecy coecets. The comparsos are base o the obectve evaluato crtera whch show measure o ose exstece, sharpess a correlato betwee the uso result a reerece mage. Fally, we specy whch type o wavelet trasorm a actvty crtero results more ormatve bra bloo vessel map. Keywors bloo vessel map, gtal subtracto agography, wavelet trasorm, uso. I. INTRODUCTION Image uso s a process by combg two or more eret mages to create a sgle composte mage. Recetly, mage uso techques have bee recevg creasg atteto the research commuty a they play mportat roles may applcatos, such as remote sesg [], mecal magg [], computer vso, a so o [3,4]. The goal o mage uso s to create mage that s more sutable, ormatve or vsual percepto or computer processg. Image uso ca be perorme at our eret stages: sgal level, pxel level, eature level, a ecso level [5]. th the evelopmet o moer mecal magg techology, mage uso mecal oma has more eectve roles [6]. Each type o mage relects eret ormato o the huma boy, whch are mportat the agoss o seases. Magetc resoace mage (MRI), compute tomography (CT), a Emsso Compute Tomography (ECT) are sample types o mecal mage. Compute tomography agography CTA, magetc resoace agography (MRA) a gtal subtracto agography (DSA) are three eret types o agography operatos. Each o them has specal role rao surgery. Commo applcatos o DSA, CTA a MRA are as ollows: aeurysm or arteroveous malormatos etecto, tumor evaluato a ssecto. -D agography s a vasve operato that uses x-rays eergy to tae pctures o bloo vessel. The mage wthout cotrast materal s ee as mas mage a the mage whch s tae ater cotrast materal ecto s cosere as cotrast mage. Ater regstrato operato or all o the mages each cotrast mage wll be subtracte rom mas mage a prouce DSA mage seres. Because the ye whch s ecte to the bloo vessel s ssolvg as tme goes, ater subtracto, the DSA seral mages wll preset eret parts o bloo vessel. Bloo vessel map ca be a result o mage uso proceure ths applcato whch s useul or octors case o surgcal operato, aeurysms, a arteroveous malormato etecto. Multresoluto trasorms have capablty o mage eatures presetato eret resoluto wth eret rectos tme a requecy oma. They are use may mecal mage uso applcatos. Laplaca pyram [7], wavelet [8], currvelet [9] are some sample trasorms ths area. I [0], authors suggeste uso o DSA seral mages base o -D screte wavelet trasorm a yamc uzzy ata moel orer to combe all the DSA mages. I [] authors propose DSA uso metho by usg Curvelet trasorm or mage ecomposto. I [] etropy rom eret level o DSA mage a a membershp ucto base o the yamc uzzy logc are use to aust the weght or mage sub-bas coecets. The goal o ths paper s extracto o bra bloo vessel map rom the DSA seral mages. e propose a uso algorthm base o the wavelet trasorm coecets a matchg egree betwee these coecets. Our metho wll be evaluate or three eret types o wavelet trasorms a our eret actvty crtera hgh requecy oma to etermate whch o them results best perormaces. The rest o ths paper s orgaze as ollows. Secto II trouces the propose mage uso algorthm. I secto III, expermet results are presete a ally, coclusos are outle secto IV. II. PROPOSED IMAGE FUSION ALGORITHM As metoe prevously, screte wavelet trasorm (DT) s use or ecomposg DSA mages to low a hgh requecy sub-bas. I our algorthm uso rules are trouce base o the characters a eatures o hgh a low requecy coecets vually. For hgh requecy uso scheme, a cotoal ecso s suggeste whch ves uso process to two parts. Actvty crtera (AC) whch are /3/$ IEEE 44

2 cosere or these coecets are base o the ege eatures. For low requecy coecets local eergy a mum selecto rule are trouce as actvty crtero a uso metho respectvely. At last by recostructg o use coecets output result wll be obtae. A. avelet Trasorm The avelet trasorm comes to solve lmtatos o xe resoluto short-tme Fourer trasorm. Dscrete wavelet trasorm (DT) allows the mage ecomposto eret s o coecets [8]. A bre troucto o wavelet trasorm s gve here. Let V Z { } resoluto aalyss (MRA): be a separable two-mesoal mult V V V, the there exst a ucto ( xy, ) { V } Z whch s calle scalg ucto, a ts traslato, Z, 0, H, V, D,(, m, ) Z () here m,, ( x, y ) s orthoormal bass or LR ( ). Gve separable two-mesoal scalg a wavelet uctos, the screte wavelet trasorm or ucto ( x, y ) wth sze M N s ee as ollow: 0 0, m, x0 y0 (, m, ) ( x, y) ( x, y) (, m, ) ( x, y) m,, ( x, y) x0 y0,, (, ) (, ) m x y xm y m, Z here,, ( x, y ) s a orthoormal bass or V. m V Z Let { } be a separable two-mesoal MRA: V V V, where { V } Z s a MRA LR ( ) wth scalg ucto, a wavelet ucto ; correspog to two mesoal scalg uctov V V, ee three uctos as ollows: { H, V, D} here 0 s a arbtrary startg scale a the ( 0, m, ) coecets ee a approxmato o ( x, y ) at scale 0.The (, m, ) coecets a horzotal, vertcal, a agoal etals or scales 0. Let 0 a select N M J so that 0,,,..., J a m, 0,,,...,. Gve the a, ( xy, ) s obtae va the verse screte wavelet trasorm as ollow: ( H ) m,, (, ), ( ) m, ( ) x y x y ( V ) m,, ( x, y ), ( x ) m, ( y ) ( D) m,, ( x, y ), ( x ) m, ( y ) ( m, ) Z ( ) here H m,, ( x, y ), ( V ) m,, ( x, y ), ( D) m,, ( x, y ) are orthoormal bases or, a ther scale traslato s () m,, ( x, y ) ( x m, y ) ( x, y) ( 0, m, ) 0, m, ( x, y) m (, m, ) m,, ( x, y) H, V, D 0 m The reverse process s complete to geerate the orgal mage. B. Hgh Frequecy Fuso Metho Hgh requecy bas relect etal ormato a slet eatures o the mage such as eges. As metoe above, the uso scheme wll be ve base o the cotoal ecso. I our algorthm, the cotoal ecso s trouce base o the matchg egree (MD) a oe threshol value (T). Matchg egree s ee as ollows: At rst or each sub-ba matrx the coecets whch are locate at the same resoluto level a o the same pot are gathere as correspog coecets set (CCS). The or each CCS varace value wll be coute as a MD. Hgher varace meas lower MD. The threshol value or each subba matrx wll be spece base o the matchg egrees. Recetly, there are may actvty crtera or hgh requecy 45

3 coecets, such as: sum eergy o graet (SEOG), local varace (LV), absolute value (AV). I our metho Summoe Laplaca () wll be trouce as a eectve actvty crtero or extracto o ege ormato a ormatve uso result. C. Sum-Moe Laplaca Sum-moe Laplaca () s use as a actvty crtero or each wavelet coecet a local wow []. I moe Laplaca (ML) absolute values o the partal seco ervatves are use. Formula s escrbe as ollow: (, ) (,, ) (,, ) ML x y x y x step y (, x step, y) (, x, y) (, x, y strep) (, x, y step) here s a typcal hgh requecy sub-ba or wavelet trasorm, s the scale o wavelet trasorm, { H, V, D} respectvely meas horzotal, vertcal a agoal rectos. I ths paper step always equals to, a or each coecet whch s locate at pot ( x, y ) s ee as: (, ( xy, )) xn yn xn yn ML (, ) here N parameter etermes the wow sze arou each pot ( x, y ). I our applcato, N s set to 5. D. Fuso Rules base o the cotoal ecso Fuso rule or each correspog coecet set whch ts varace s hgher tha threshol value s ee as ollows: ( xy, ) ( ) here s mum value or relate CCS. ( m,, ) ( m,, ) here (, m, ) s use coecet or scale a sub-ba { H, V, D} a (, m, ) s the coecet wth mum value, {,,... } s set o rame umbers that wll be use uso process. For each CCS that ts varace s lower tha the threshol value uso rule s cosere as ollows: (,, ) m ( m,, ) here ( m,, ) s weght or the coecet that locate o the pot ( m, ), or scale a subba { H, V, D}, rom rame {,,... }. (, m, ) ( m,, ) (, m, ) (, m, ) ( m,, ) ( m,, ) here (, m, ) s use coecet. (, m, ) () E. Low requecy coecet uso metho Low-requecy sub-ba cotas most o the mage ormato a cocetrates most o the mage eergy. Local eergy (LE) [3] s use as AC to choose the low requecy coecets. The algorthm base o the 3 3 wow s ee as ollows: M, N (0) LE ( x, y) R( x, y ). ( x, y ) here R s the local lterg operator. M, N s the scope o local wow o, (0) ( x, y) s ee as a local wow wth low requecy coecets. (0) (0) (0) LE (, xy) E* (, xy) E * (, xy)... E* (, xy),,... here LE ( x, y) s the local eergy or coecet (0) ( x, y) whch s cetere at pot( x, y ), rom rame {,,... }. E, E,... E a E are the lter operators eret rectos. I ths paper, we use three rectoal lterg operators or low requecy as ollows. 0 E E E The uso rule or low requecy coecets s ee as ollows: LE (LE ( x, y)) 46

4 here LE s mum value. TABLE I. OBJECTIVE EVALUATION CRITERION ( x, y ) ( x, y ) EVALU ATION CRITERI A Formula Descrpto s the use coecet a ( x, y) where ( x, y) s the coecet wth mum local eergy value rom rame ( {,,..., } ). III. EXPERIMENTAL RESULTS To test our algorthm, ty agography operato veos rom Chamra hosptal are gathere. Twety o them show aeurysm problem a rest o them are healthy samples whch ollow DICOM staar. All o the rames have the same sze o wth 56-level grayscale. Fel o vew (FOV) s 7cm. I our expermet each DSA mage s ecompose to 4-levels usg Haar wavelet trasorm (HT), Dscrete Meyer wavelet trasorm (DMT) a Symlets wavelet trasorm (ST). Ater tal expermetato wth to 4 levels, the level o ecomposto s restrcte to our. As metoe secto, the threshol value or cotoal ecso wll be spece base o the varace values whch are obtae or all o the correspog coecets sets oe sub-ba. I our expermets mea o these varaces s ee as the threshol value. Base o the secto,, SEOG a LV a local wow wth sze 55arou each coecet a absolute value, are cosere as actvty crtero or hgh requecy coecets. I our expermets, the uso methos or each type o DT are eret base o these hgh requecy AC but or low requecy oma actvty crtero s same or all o them. There are may obectve a subectve evaluato crtero (EC) whch are trouce or evaluatg uso results [4]. I ths paper, correlato coecet (CC), staar vso (STD), spatal requecy (SF), pea sgal-to-ose rato (PSNR), root mea square error (RMSE) are use. Table trouces these obectve evaluato crtera. I ths paper reerece mage a uso result are ame R a F wth sze respectvely. a mea value o ( R) a ( F) A. Exprmet Comparg uso methos or vessel map extracto base o three eret wavelet trasorms Table to 4 show the evaluato perormaces base o the HT, ST a DMT, respectvely. It's obvous that the CC, RMSE a PSNR crtera or DMT base uso results have best values. Base o the STD a SF values we ca ot specy whch type o wavelet trasorms has the best results but we ca coclue that or each metho erece o values betwee three types o T are ot promet. Cosequetly uso methos base o the DMT have better perormaces. CC ( F(, ) ( F))( R(, ) ( R)) F Corr ( ) R ( F(, ) ( F)) ( R(, ) ( R)) STD NM STD F(, ) F SF PSNR SF ( RF ) ( CF ) RF ( F (, ) F (, )) CF ( F (, ) F (, )) PSNR 55 0 log( ) ( F(, ) R(, )) RMSE RMSE ( F (, ) R(, )) TABLE II. THE FUSION RESULTS BASED ON HT CC shows egree o correlato betwee mages. hgher CC meas better uso result Ths crtero Relects the sprea the mage. Larger STD cates rcher etale ormato a better uso result. Ths crtero measures the overall actvty a clarty level a mage, hgher SF meas better result. PSNR s use to measure qualty o the use mage. RMSE s cumulatve square error betwee the merge a the orgal mage. lower RMSE results better qualty. Evaluato Crtera Metho CC STD SF RMSE PSNR LV SEOG AV TABLE III. THE FUSION RESULTS BASED ON ST Evaluato Crtera Metho CC STD SF RMSE PSNR LV SEOG AV

5 TABLE IV. THE FUSION RESULTS BASED ON DMT Evaluato Crtera Metho CC STD SF RMSE PSNR LV SEOG AV (a) (b) trasorms are use., SEOG, LV a AV are cosere as actvty crtera or hgh requecy coecets. By suggestg a cotoal ecso or hgh requecy oma uso rules are ve to mum selecto a weghte averagg methos whch results ose reucto uso results. Maxmum local eergy s trouce as the low requecy uso metho whch mproves vsblty characterstc o the output. From perormaces whch are represete Table to 4 we coclue that uso results base o the DMT have the best perormaces. From outputs a perormaces whch are show Fg. a Table. 4 we clam that uso metho base o the has more ormatve bloo vessel map whch shows ty vessels more qualy. (c) () Fg.. The uso results base o DMT. (a) SEOG metho, (b) AV metho, (c) LV metho a () metho. B. Exprmet Comparg uso methos or vessel map extracto base o the actvty crtero I last part, we coclue that uso methos base o the DMT wll have better results tha usg HT a ST. I ths secto we wat to specy whch metho o uso results best perormaces. As t s obvous rom Table 4 or CC, RMSE a PSNR crtera, base uso metho has best values betwee three others uso methos (SEOG, LV, a AV). It shows that by usg as a actvty crtero hgh requecy oma, uso result has lower error a hgher correlato wth reerece mage. I ths Table STD a SF values have ot promet ereces betwee all o the methos. AV a SEOG uso methos have hghest value or these two crtera. Fg. shows the best results by usg DMT. Fg. (a) shows the result o SEOG base uso metho wth low resoluto, low qualty a hgh ose perormaces. Fg. (b), (c), () show results o AV, LV a base uso methos, respectvely. e ca coclue that by usg AV, LV a as actvty crtera hgh requecy oma, uso results wll have hgh correlato coecet, lower ose a better vsual perormace. C. Fal results As a al result base o the expermets whch were scusse above we coclue that uso metho base o the DMT wth 4 ecomposto levels wth a LE as a actvty crtero or hgh a low requecy coecets has more qualy a ormatve result bloo vessel map extracto applcato. IV. DISCUSSION I ths paper we propose a uso algorthm or DSA seral mages. I our metho three eret types o wavelet REFERENCES [] L. Alparoe, L. al, J. Chaussot, C. Thomas, P. Gamba, a L.M, Bruce, "Comparso o Pasharpeg Algorthms: Outcome o the 006 GRS-S Data-Fuso Cotest," Geoscece a Remote Sesg, IEEE Trasactos o, vol.45, o.0, pp.30,30, Oct. 007 [] M. Nemeer, M. D. Abramo, B. va Gee, "Iormato Fuso or Dabetc Retopathy CAD Dgtal Color Fuus Photographs," Mecal Imagg, IEEE Trasactos o, vol.8, o.5, pp.775,785, May 009 [3] L. Saro, G. Luca Forest, R. Nu, P.K. Varshey, Sesor uso or veo survellace, : Proceegs o the 7th Iteratoal Coerece o Iormato Fuso, Stocholm, Swee, vol., pp , 004 [4] S. Jabr, Z. Durc, H. echsler, Detecto a locato o people veo mages usg aaptve uso o color a ege ormato, Proc. 5th It. Co. Patter Recogto, vol. 4, pp ,.000. [5] X. Da, S. Khorram, Data uso usg artcal eural etwors: a case stuy o multtemporal chage aalyss. Comput. Evro. Urba Syst.Vol.3,pp.9-3,ISSN , 999. [6] C.S. Pattchs, M.S. Pattchs, E. Mchel-Tzaaou, Mecal magg uso applcato: a overvew, Aslomar Coerece o Sgals, Systems a Computers, vol., pp , 00. [7] P.J. Burt, a E.H. Aelso, "The Laplaca Pyram as a Compact Image Coe," Commucatos, IEEE Trasactos o, vol.3, o.4, pp , Apr 983. [8] G Paares, J Mauel e la Cruz, A wavelet-base mage uso tutoral, Patter Recogto, vol. 37, pp , Sep [9] E. J. Caes, L. Demaet, D. L. Dooho, a L. Yg, Fast screte curvelet trasorms, SIAM Multscale Moel. Smul, vol. 3, pp , 006. [0] G. Zhag, Y. Zheg, J. u a Z. Cu, "avelet Fuso DSA Base o Dyamc Fuzzy Data Moel," Boormatcs a a Bomecal Egeerg, 009. ICBBE r Iteratoal Coerece o, pp.-4, -3 Jue 009. [] G. Zhag, Z. Cu, F. L, J. u, " DSA Image Fuso Base O Dyamc Fuzzy Logc a Cutvelet Etropy", Joural o MultMea, vol. 4, o. 3, pp.9-36, JUNE 009. [] Z. Hu, L. Q, F. Huau, Mult-ocus color mage uso the HSI space usg the sum-moe-laplaca a a coarse ege map, Image a Vso Computg, vol. 6, o. 9, pp , 008. [3] H. Lu, L. Zhag, S. Serawa, Maxmum local eergy: A eectve approach or multsesor mage uso beyo wavelet trasorm oma, Joural o Computers & Mathematcs, vol. 64, o.5, pp , 0. [4] V. Petrov, C. Xyeas, Obectve Evaluato o Sgal-level Image Fuso Perormace, Optcal Egeerg, vol. 44, o. 8,