31 research outputs found
Non-linear subdivision using local spherical coordinates
In this paper, we present an original non-linear subdivision scheme suitable for univariate data, plane curves and discrete triangulated surfaces, while keeping the complexity acceptable. The proposed technique is compared to linear subdivision methods having an identical support. Numerical criteria are proposed to verify basic properties, such as convergence of the scheme and the regularity of the limit function
Steganography for Three-Dimensional Polygonal Meshes
This paper proposes a method to embed information into a 3D model represented by a polygonal mesh. The approach used consists in slightly changing the position of the vertices, in uencing the length of approximation of the normals to the surface. This technique exhibits relatively low complexity, and o ers robustness to simple geometric tranformations. In addition, it does not introduce any visible distortion to the original model
An ordered topological representation of 3D triangular mesh facial surface: concept and applications
MESH: Measuring Errors between Surfaces using the Hausdorff distance
This paper proposes an efficient method to estimate the distance between discrete 3D surfaces represented by triangular 3D meshes. The metric used is based on an approximation of the Hausdorff distance, which has been appropriately implemented in order to reduce unnecessary computations and memory usage. Results show that when compared to similar tools, a significant gain in both memory and speed can be achieve
Real-Time Phase Recovery of Biologicall Cell in Digital Holographic Microscopy by Use of a Self-Calibration Hologram
We demonstrate in Digital Holographic Microscopy a self-calibration hologram method allowing aberrations compensation and a real-time biological cell phase recovery by using a single hologram without adjustment of any parameters
Process engineering and failure analysis of MEMS and MOEMS by Digital Holography Microscopy (DHM)
Process engineering and failure analysis of MEMS and MOEMS require static and dynamical characterization of both their in-plane and out of plane response to an excitation. A remarkable characteristic of Digital Holography Microscopes (DHM) is the extremely short acquisition time required to grab the whole information necessary to provide 3D optical topography of the sample: a unique frame grab, without any vertical or lateral scan provides the information over the full field of view. First, it ensures DHM measurements to be insensitive to vibrations. Second, it opens the door to fast dynamical characterization of micro-systems. For periodic movement analysis, DHM can operate in stroboscopic mode with standard cameras. It enables precise characterization up to excitation frequencies of 100 kHz with recovery cycle of 10% simply by triggering properly the camera. Pulsed sources can be used for investigation of higher excitation frequencies. For non periodic movement analysis fast acquisition cameras and postponed treatment are used. DHM are therefore unique and very efficient tool for dynamical characterization of in- plane and out-of-plane response. In this paper we show the basics of the technology and illustrate process engineering and failure analysis using DHM with an example of in and out of plane characterization of movements of a variable capacitor using the stroboscopic mode of acquisition