Shape and Expression Space of Real istic Human Faces

Transcription

1 Vol8 No5 JOURNAL OF COMPU TER2AIDED DESIGN & COMPU TER GRAPHICS May 2006 ( 0087) pku. edu. cn) : Canny ; ; ; TP394 Shape and Expression Space of Real istic Human Faces Pei Yuru Zha Hongbin ( N ational L aboratory on Machi ne Perception Peki ng U niversity Beiji ng 0087) Abstract We present a novel method to generate a parameterized space of human facial scans Our ap2 proach is under an energy minimization f rame The optimization solves t he displacement vector at each ver2 tex on the base mesh The error metrics include the following terms : distance surface smoothness and fea2 t ure const raint s including curves boundaries and marker pairs Wit h t he template fitting to static expression scans with the same algorithm an expression space is generated as well The feature curves are automatical2 ly extracted from expression maps with an edge detection algorithm Such feature curves are used to reduce t he dimensionality of t he shape space The consistent parameterization in neut ral faces and expressions forms the basis of a large category of applications eg shape morphing texture transferring and expression trans2 ferring In view of the similarity between feature curves on depth images and those on 2D line drawings of cartoons t he nonlinear optimization is employed to realize t he dramatic expression t ransfer f rom cartoons on2 to realistic facial models Key words scans ; template fitting ; correspondence establishment ; t ransfer ; shape blending 0 : ; : : ( ) ; (2004CB38005)

2 Noh [6 ] Sumner [2 ] [829 2 ] Sloan [0 ] RBF Canny Wang [ ] Blanz Joshi [3 ] 2 50 (iterative closest point s ICP) [ ] ; Sumner [2 ] ICP 20 ; 6 ( Ek2 [3 ] man [4 ] ) : ; 3 [425 ] : 2 T (radial basis function RBF) [627 ] [2 ] (20 30 )

3 5 : 65 P = ( p p 2 p 3 p 3 N ) 2 N ( N < n) 3 ( ) ( ) Allen [3 ] w i ( T + + P) -^D ) 2 2 -^ ; w i 2 C D T = ( x y z x 2 z n - x n y n z n ) B T 2 b D = ( x y z x 2 z m - x m y m z m ) D a ( F T F D ) v k T = v k T + v k T v k T = ( p 3 k q 3 k + p 3 k + 2 ) T + + P = D T + T + 32 : N 3 N DFP (Davidon2Flatcher2Powell) E d = N i = ; v i T v i T 32 vd i : ) 20 : M T M D 2 a 2) B D 3)

4 F T F D F T ( 2 d : ) F T F D F T = { v 0 T v T v j - T v j T v p T} F D = { v 0 D v D v k D - vd k vd q } v j T F T Π p v i T - v i - T i = F D ( r k - r k ) k - r k - = v D - i v i - i = v j D = ( v k - D ( r k - D Π q i = v D - i v i D - r) + vd k ( r - r k - ) )Π( r k - r k - ) E f ( P) = ( M T + P) - M D ) r = v i T - i = v i - T r k = k v D - i v i D Π q - v D - i v i - D ; i = i = S 0 r ( r k - r k ) S i = S i - S 0 S ( 3 ) S = S 0 + i S i ( B T + P) - B D ) 2 + ( F T + P) - 33 F D ) 2 v i T Ring ( v i T) = { v j T ( i j) Edges ( T) } E s ( P) = N ( Ri ng ( v i T) - 2 i = v i T - v j T 2 ) Ring ( v i T ) 3 3 N M = 6 (principle component analysis PCA) [9 ] 4 E ( P) = w s E s + w d E d + w f E f A

5 5 : % S i A RBF RBF ( v j ) = S N + i = i h ( a i - v j ) j = N h ( r) = r 2 + c Hardy 2 multi2quadrics E s ( P S ) = a i A N Ri ng ( v i T) - 2 v i - v j 2 i = Ring ( v i T ) N + N + < N N [5 ] 2 sweep S i [6 ] 2 ( 7 c ) 4 L C = { l i C i = 4} ( 7 c ) ( 7 b ) 7

6 L S = { l i S i = 4} 6 2 min ( E ( ) = ( l k C - k i ls k i ) 2 i 5 ( 8 c ) [ ] Besl P J Mckay N D A method for registration of 3D shapes [J ] IEEE Transactions on Pattern Analysis and Machine Intel2 ligence (2) : [ 2 ] Sumner R W Popovic J Deformation transfer for triangle meshes [ C] ΠΠComputer Graphics Proceedings Annual Confer2 ence Series ACM SIGGRAPH Los Angeles California 2004 : [ 3 ] Allen B Curless B Popovic Z The space of all body shapes : : ( 3 ) ( 5 reconstruction and parameterization from range scans [ C] ΠΠComputer Graphics Proceedings Annual Conference Series ACM SIGGRAPH San Diego California 2003 : ) ( 8 d ) [ 4 ] Allen B Curless B Popovic Z Articulated body deformation ( 7 ) from range scan data [ C] ΠΠComputer Graphics Proceedings Annual Conference Series ACM SIGGRAPH San Antonio Texas 2002 : [ 5 ] Marschner S R Guenter B Raghupathy S Modeling and ren2 dering for realistic facial animation [ C] ΠΠProceedings of the th Eurographics Workshop on Rendering Brno Czech Republic 2000 : [ 6 ] Noh J Y Neumann U Expression cloning [ C] ΠΠComputer Graphics Proceedings Annual Conference Series ACM SIG2 GRAPH Los Angeles California 200 : [ 7 ] Pei Y Zha H Yuan Z Tissue map based craniofacial recon2 struction and facial deformation using RBF network [ C] ΠΠProceedings of the 3rd International Conference on Image and Graphics Hong Kong 2004 : [ 8 ] Na K J ung M R Hierarchical retargeting of fine facial motions 8 [J ] Computer Graphics Forum (3) :

7 5 : 69 [ 9 ] Pyun H Kim Y Chae W et al An example2based approach for facial expression cloning [ C] ΠΠProceedings of Symposium on Computer Animation San Diego California 2003 : [ 0 ] Sloan P J Rose C F Cohen M F Shape by example [ C] ΠΠProceedings of Symposium on Interactive 3D Graphics Re2 search Triangle Park North Carolina 200 : [ ] Wang Y Huang X Lee C S et al High resolution acquisi2 tion learning and transfer of dynamic 32D facial expressions [J ] Computer Graphics Forum (3) : [ 2 ] Blanz V Basso C Poggio T et al Reanimating faces in im2 ages and video [J ] Computer Graphics Forum (3) : [ 3 ] Joshi P Tien W C Desbrun M Learning controls for blend shape based realistic facial animation [ C] ΠΠProceedings of Sym2 posium on Computer Animation San Diego California 2003 : [ 4 ] Ekman P Emotion in the human face [ M ] New York : Cam2 bridge University Press 982 [ 5 ] Bregler C Covell M Slaney M Video rewrite : driving visual speech with audio [ C] ΠΠComputer Graphics Proceedings Annu2 al Conference Series ACM SIGGRAPH Los Angeles Califor2 nia 997 : [ 6 ] Blair P Cartoon animation [ M ] Laguna Hills : Walter Foster l962