Active Visual Inference of Surface Shape - Roberto Cipolla Part 1 ppt

... Motivation 1 1. 1 .1 Depth cues from stereo and structure from motion 1 1. 1.2 Shortcomings 5 1. 2 Approach 7 1. 2 .1 Visual motion and differential geometry 7 1. 2.2 Active vision 7 1. 2.3 Shape ... 1. 2.4 Task oriented vision 9 1. 3 Themes and contributions 9 1. 3 .1 Curved surfaces 9 1. 3.2 Robustness 10 1. 4 Outline of book 11 Surface Shape from the Defor...

Ngày tải lên: 10/08/2014, 01:22

... reactions [13 3] and in the recovery of 3D shape up to a relief transformation [13 0, 13 1]. 5.3. Differential invariants of the image velocity field 13 5 are cancelled out. By taking the difference of ... direction of F and the slant and tilt of the surface (o-, r) is given by: IF I = tanc~ (5.23) ZF = T (5.24) With this new notation equations (5 .16 , 5 .17 , 5.]8 and...

Ngày tải lên: 10/08/2014, 01:22

... interpretation of random-dot stereograms have shown that even with sparse data the human visual system arrives at unique interpretations of surface shape - the perception of dense and coherent surfaces ... knowledge about the proposed surface to resolve ambiguity in the stereo matching problem - integrating matching and surface interpolation [10 1, 17 0, 15 3]. A....

Ngày tải lên: 10/08/2014, 01:22

... In Proc. 1st British Machine Vision Conference, pages 6 7-7 2, 19 90. 18 8 Bibliography [12 5] [12 61 [12 7] [12 8] [12 9] [13 o] [13 1] [13 2] [13 3] [13 4] [13 5] [13 6] [13 7] [13 8] [13 9] J.J. ... (V.q) 1 2A(U.q)2.] (U.n) 2 + U n ~;t2 + (U.n)2 J [ ~2~-A q)'U :~ln12 ] (D.7) -a.n i (v.n)2 + (u.~) ~ (D.6) Bibliography 18 7 [11 0] [11 6]...

Ngày tải lên: 10/08/2014, 01:22

... they 14 Chap. 2. Surface Shape from the Deformation of Apparent Contours Figure 2 .1: A smooth curved surface and its silhouette. A single image of a smooth curved surface can provide 31) shape ... images of curved surfaces and robustness. 1. 3 .1 Curved surfaces Visual cues to curved surface shape include outlines (apparent contour [12 0]), silhouettes, speculari...

Ngày tải lên: 10/08/2014, 01:22

... the shape of the rim, a convexity of the contour corresponds to a convex patch of surface, a concavity to a saddle-shaped patch. Inflections of the contour correspond to flexional curves of ... sign(t~ n) = -sign(w.L(w)) = -( a)Usign(g t) - 2aj31rslsign(p.L(rs) ) - (/31rsl)2sign(n s) = -( a)2sign(n t) - (/3]rs D2sign(n s) (2.32) since by the conjugacy r...

Ngày tải lên: 10/08/2014, 01:22

... Contours - Implementation Estimated radius of curvature (mm) 90 70 -~ 5 0-& quot; 40 ~ :ils -1 .o -o.s 0:s 1. o 1. 8 Error in edge Iocalisation (pixels) -1 0 Figure 3 .11 : Sensitivity of curvature ... -2 .5 -1 .5 -0 .5 0.5 ~ 1. 5 2.5 Error in position (mm) -5 0 i "~ -1 50 Estimated radius of curvature (mm) 250 I 2oo i I 15 0 ' i...

Ngày tải lên: 10/08/2014, 01:22

... curve (4 .16 ) rss.n v Aip ~12 (4 .19 ) N.n v Ax (1 - (p.T):)" (4.20) t~P Substituting (4 .15 ) and (4 .11 )for nP: tr p = Ate = Ate N.(p A T) (4. 21) (1 - (p.T)2) 3/2 B.p (4.22) (1 - (p.T)2) ... for a: N.n p (1 - (p.m)~) a p a -~ -( 1- (p.m)2). (4.37) Differentiating (4.20) and rearranging we can recover the other component, /3: at p...

Ngày tải lên: 10/08/2014, 01:22

... (deformation) components. v~, vy - 7 7- 1 0 + T 0 1 + 2 sin it cos It 0 - 1 - sin It cos It curl'7 [ 0 -1 ] div-7[ 1 0] def~7[cos2it sin2#] - 2 1 0 +T 0 1 + 7- sin2it -cos2# where curl'S, ... the surface orientation (A~/A, Ay/A). From (5.2) to (5 .13 ) we have: U1 U0 ~-~ 2 A U2 v0 - + f ~1 A curl~ = -2 ~3 + (-VlAy + U2A...

Ngày tải lên: 10/08/2014, 01:22

... zoom control of the cameras [58, 13 2, 39, 11 ]. A.5 Monocular shape cues A.5 .1 Shape from shading Shape from shading is concerned with finding ways of deducing surface orienta- tion from image ... the surface texture. These include homogeneity (uniform density distri- bution of texture elements - texels) or isotropy (uniform distribution of orien- tations...

Ngày tải lên: 10/08/2014, 01:22