Issue No.03 - March (2012 vol.18)
Ricardo Marroquim , Universidade Federal do Rio de Janeiro, Rio de Janeiro
Marco Callieri , ISTI-CNR, Pisa
Paolo Cignoni , ISTI-CNR, Pisa
Roberto Scopigno , ISTI-CNR, Pisa
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TVCG.2011.75
The projection of a photographic data set on a 3D model is a robust and widely applicable way to acquire appearance information of an object. The first step of this procedure is the alignment of the images on the 3D model. While any reconstruction pipeline aims at avoiding misregistration by improving camera calibrations and geometry, in practice a perfect alignment cannot always be reached. Depending on the way multiple camera images are fused on the object surface, remaining misregistrations show up either as ghosting or as discontinuities at transitions from one camera view to another. In this paper we propose a method, based on the computation of Optical Flow between overlapping images, to correct the local misalignment by determining the necessary displacement. The goal is to correct the symptoms of misregistration, instead of searching for a globally consistent mapping, which might not exist. The method scales up well with the size of the data set (both photographic and geometric) and is quite independent of the characteristics of the 3D model (topology cleanliness, parametrization, density). The method is robust and can handle real world cases that have different characteristics: low level geometric details and images that lack enough features for global optimization or manual methods. It can be applied to different mapping strategies, such as texture or per-vertex attribute encoding.
Computer graphics, image color analysis.
Ricardo Marroquim, Marco Callieri, Paolo Cignoni, Roberto Scopigno, "Flow-Based Local Optimization for Image-to-Geometry Projection", IEEE Transactions on Visualization & Computer Graphics, vol.18, no. 3, pp. 463-474, March 2012, doi:10.1109/TVCG.2011.75