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A technique is presented to construct a multiscale representation of planar contours based on the multiwavelet transform (MWT). To generate this multiwavelet description, a partial 1-D discrete multiwavelet transform (DMWT) is applied to the vertical and horizontal components of a length-parametrized planar curve. This multiscale representation descomposes(More)
This paper proposes a combination of contour deformation modelling in Sobolev spaces and the Condensation filter to track an object over a sequence of images. As Sobolev spaces are smoothness spaces this allows to control the smoothness of the contour deformation extending previous wavelet representations. We also introduce a probabilistic model for the(More)
This paper describes the Discrete Focal Stack Transform (DFST) that computes the focal stack (a collection of photographs focused at different depths) from a lightfield. It proposes a new discretization of the Photography operator based on the interpolation of the lightfield by means of 4D trigonometric polynomials and an approximation to the integration(More)
This article depicts an integrated system capable of generating virtual stereo scenes, reconstructing a three-dimensional map of distances, and calculating the accuracy of the results obtained. This tool is particularly useful for verifying the validity of distance reconstruction techniques, and is robust enough to use in a wide variety of scenarios since(More)
This paper proposes a new model for contour deformations using wavelets. This model uses Sobolev spaces to control the smoothness of the contour deformation. This formulation defines a probabilistic model that induces a prior distribution for contour deformation. Based on this distribution, the fitting problem is solved in bayesian terms. The deformation(More)
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