Publications

• Crude Registration of Range Images through Matching of their Simplified Meshes [pdf]
  Authors:Mercedes Rocío Gonzalez Márquez and Wu Shin-Ting
  Published in Proceedings of Computer Graphics and Imaging (CGIM 2010)
  Abstract
  tructing a tri-dimensional model from range images, they must be registered, i.e., it must be put together into the same coordinate system. There are good algorithms available to perform this, but only after the range images have been brought into positions that are close to the true ones with respect to an arbitrarily chosen reference system. These initial estimates are often provided manually. This paper deals with a technique to compute them automatically. We present a way to determine parameter values that are necessary to control the control ow of a simpli ed mesh based crude registration, which is characterized by two novel features: drastic data reduction and an expressive shape descriptor.
• An automatic crude registration of two partially overlapping range images [pdf]
  Authors:Mercedes Rocío Gonzalez Márquez and Wu Shin-Ting
  Published in Proceedings of SIBGRAPI'2008
  Abstract
  We present a crude registration algorithm for two partially overlapping range images acquired from a rigid object. Our proposal is characterized by two novel features: drastic data reduction and expressive shape descriptor. The data reduction is achieved on the basis of the observation that for crude alignments only the overall shape of image is of interest and the enhancement of the expression power of the shape descriptor is accomplished by integrating in it both local and global shape information. Experimental results show that our algorithm delivers good initial estimate to a fine registration program.
• On Reconstructing Surfaces of Arbitrary Topology from a Range Image [pdf|ps]
  Authors: Mercedes G. Márquez, Wu Shin-Ting and Rosana M.da Silva
  Published in Proceedings of SIBGRAPI'2001, Gramado, Brazil, 2001
  Abstract
  To reconstruct a topologically consistent 3D surface model is a challenging problem. In this paper we present an algorithm that estimates from a range image, without registering and converting it into a volumetric data, the most probable topology of a surface to be reconstructed. In our algorithm we start with a closed initial mesh and preserve its closeness during the reconstruction process. Some experiments were carried out to validate our proposal.
• Reconstructing a 3D-Model from an Unregistered Range Image[pdf|ps]
  Authors: Wu Shin-Ting, Rosana M. da Silva and Mercedes G. Márquez
  Published in Proceedings of International Conference on Imaging Science, Systems, and Technology , conference proceeding, Las Vegas, EUA, 2000
  Abstract
  In this paper we present yet another reconstruction technique which generates a 3D closed triangular mesh from an unregistered range image by deforming discretely an initial triangular mesh. Combining the advantages of the previous work on a deformable model and on a function-graph model, our algorithm avoids not only holes in the reconstructed surfaces, but also self-intersections as well.
• Reconstructing a 3D Model from Range Images Using Radial Flow Model[pdf|ps]
  Authors:Rosana M. da Silva and Wu Shin-Ting
  Publishhed in Proceedings of SIBGRAPI'98, Rio de Janeiro, Brazil, 1998
  Abstract
  The reconstruction of a 3D model from range images can be conveniently split into two stages. The first stage consists basically in the extraction of geometrical information, e.g. the depth and the orientation of image points, and the second stage concentrates on the transformation of these data to a 3D model.
  In this paper we focus on the second stage. Our approach is based on a deformable model, which offers more flexibility to mold a 3D model according to several geometrical constraints. Moreover, instead of looking for a global functional that carries out the deformation, we opted for establishing discrete local correspondences between 3D surface point data extracted from images and 3D model points.

• Registro Inicial de Imagens de Profundidade via Malhas Simplificadas[pdf]
  Author: Mercedes Gonzales Marquez
  Type: Doutorado
  
• Mudanças topológicas em um modelo deformável no ajuste a uma imagem de profundidade [ps]
  Author: Mercedes Gonzales Marquez
  Type: Mestrado
• Reconstrução de um modelo 3D a partir de imagens de profundidade usando modelos deformáveis,[pdf|ps]
  Author: Rosana Marques da Silva
  Type: Doutorado

• Relatório Técnico Nro.3 à FAPESP, 2003 [ps]
  Author:Mercedes Gonzales Marquez
• Relatório Técnico Nro.2 à FAPESP, 2002 [ps]
  Author: Mercedes Gonzales Marquez

• Using simplified meshes for crude registration of two partially overlapping range images [pdf]
  Authors:Mercedes Rocío Gonzalez Márquez and Wu Shin-Ting
  Published in Proceedings of WSCG 2007
  Abstract
  We present an efficient algorithm for crude registration of two partially overlapping range images. The central focus of our work is how to filter out the wrong pairs efficiently in order to reduce the search space. Motivated by the availability of robust and efficient mesh simplification algorithms, such as the QSLIM software package, which preserve the main characteristics of the surface shape, we propose to find a good initial transformation estimate on the basis of the vertices of simplified meshes, instead of the original dense sets of range data. Promising results, that make the iterative closest point matching procedure converges to a correct final alignment, are provided.
• On Reconstructing Surfaces with Genus Greater than Zero from Range Images
  Authors: Mercedes G.Marquez and Wu Shin-Ting
  Published in SIBGRAPI'2000 conference proceeding
• Reconstrução de objetos 3D usando Modelos Deformáveis [pdf]
  Authors: Rosana M. da Silva and Wu Shin-Ting
  Published in SIBGRAPI'1997 conference proceeding