724 research outputs found
Hyperbolic polyhedral surfaces with regular faces
We study hyperbolic polyhedral surfaces with faces isometric to regular
hyperbolic polygons satisfying that the total angles at vertices are at least
The combinatorial information of these surfaces is shown to be
identified with that of Euclidean polyhedral surfaces with negative
combinatorial curvature everywhere. We prove that there is a gap between areas
of non-smooth hyperbolic polyhedral surfaces and the area of smooth hyperbolic
surfaces. The numerical result for the gap is obtained for hyperbolic
polyhedral surfaces, homeomorphic to the double torus, whose 1-skeletons are
cubic graphs.Comment: 23 pages, 3 figures. arXiv admin note: text overlap with
arXiv:1804.1103
3-D Shape Matching for Face Analysis and Recognition
The aims of this paper are to introduce a 3-D shape matching scheme for automatic face recognition and to demonstrate its invariance to pose and facial expressions. The core of this scheme lies on the combination of non-rigid deformation registration and statistical shape modelling. While the former matches 3-D faces regardless of facial expression variations, the latter provides a low-dimensional feature vector that describes the deformation after the shape matching process, thereby enabling robust identification of 3-D faces. In order to assist establishment of accurate dense point correspondences, an isometric embedding shape representation is introduced, which is able to transform 3-D faces to a canonical form that retains the intrinsic geometric structure and achieve shape alignment of 3-D faces independent from individual’s facial expression. The feasibility and effectiveness of the proposed method was investigated using standard
publicly available Gavab and BU-3DFE databases, which contain faces expressions and pose variations. The performance of the system was compared with the existing benchmark approaches and it demonstrates that the proposed scheme provides a competitive solution for the face recognition task with real-world practicality
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