Jens Ackermann

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View interpolation and image-based rendering algorithms often produce visual artifacts in regions where the 3D scene geometry is erroneous, uncertain, or incomplete. We introduce ambient point clouds constructed from colored pixels with uncertain depth, which help reduce these artifacts while providing non-photorealistic background coloring and emphasizing(More)
We present a photometric stereo technique that operates on time-lapse sequences captured by static outdoor webcams over the course of several months. Outdoor webcams produce a large set of uncontrolled images subject to varying lighting and weather conditions. We first automatically select a suitable subset of the captured frames for further processing,(More)
We present a feature-sensitive remeshing algorithm for relaxation-based methods. The first stage of the algorithm creates a new mesh from scratch by resampling the reference mesh with an exact vertex budget with either uniform or non-uniform vertex distribution according to a density function. The newly introduced samples on the mesh surface are(More)
Understanding biological evolution prompts for a detailed understanding of the realized phenotype. Biochemical and gene regulatory dynamics are a cornerstone for the physiology of the cell and must therefore be regarded as one of the major aspects of such a phenotype. Experimental insight into molecular parameters is, however, hard to come by. Model(More)
The properties of poly(3-hydroxybutyrate) combined with the fact that it can be produced easily by numerous prokaryotes from renewable resources and even from potentially toxic waste products using well-known fermentation processes have generated keen interest in this biopolyester as a substitute for chemo-synthetic petroleum-derived polymers in many(More)
We present a novel multi-view photometric stereo technique that recovers the surface of textureless objects with unknown BRDF and lighting. The camera and light positions are allowed to vary freely and change in each image. We exploit orientation consistency between the target and an example object to develop a consistency measure. Motivated by the fact(More)
We introduce an example-based photometric stereo approach that does not require explicit reference objects. Instead, we use a robust multi-view stereo technique to create a partial reconstruction of the scene which serves as sceneintrinsic reference geometry. Similar to the standard approach, we then transfer normals from reconstructed to unreconstructed(More)
The design of DNA sequences plays a fundamental role for many biomolecular applications and is one of the most important theoretical tasks to fathom the potential of molecular information processing. Optimization strategies have been based on the model of stiff “digital” polymers by counting the number of base mismatches (Hamming distance and related(More)