Clemens Birklbauer

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We present a first approach towards panorama light-field imaging. By converting overlapping sub-light-fields into individual focal stacks, computing a panoramic focal stack from them, and converting the panoramic focal stack back into a panoramic light field, we avoid the demand for a precise reconstruction of scene depth.
We present a first approach to light-field retargeting using z-stack seam carving, which allows light-field compression and extension while retaining angular consistency. Our algorithm first converts an input light field into a set of perspective-sheared focal stacks. It then applies 3D deconvolution to convert the focal stacks into z-stacks, and(More)
Light-field cameras offer new imaging possibilities compared to conventional digital cameras. However, the additional angular domain of light fields prohibits direct application of frequently used image processing algorithms, such as warping, retargeting, or stitching. We present a general and efficient framework for nonuniform light-field warping, which(More)
We present a simple guided super-resolution technique for increasing directional resolution without reliance on depth estimation or image correspondences. Rather, it searches for best-matching multidimensional (4D or 3D) patches within the entire captured data set to compose new directional images that are consistent in both the spatial and the directional(More)
We present a novel approach for guided light-field photography using off-the-shelf smartphones. In contrast to previous work that requires the user to decide where next to position a mobile camera, we actively compute and visualize during runtime a recommendation for the next sampling position and orientation taking into account the current camera pose and(More)
Our sensor [Koppelhuber and Bimber 2013] consists of a thin, transparent polycarbonate film, referred to as luminescent concentrator (LC), that is doped with fluorescent dyes. Light of a particular wavelength sub-band that penetrates the film is emitted in longer wavelengths, while wavelengths outside the sub-band are fully transmitted. The example shown in(More)
We present an angular superresolution method for light fields captured with a sparse camera array. Our method uses local dictionaries extracted from a sampling mask for upsampling a sparse light field to a dense light field by applying compressed sensing reconstruction. We derive optimal sampling masks by minimizing the coherence for representative global(More)
We present a fully transparent and flexible light-sensing film that, based on a single thin-film luminescent concentrator layer, supports simultaneous multi-focal image reconstruction and depth estimation without additional optics. Together with the sampling of two-dimensional light fields propagated inside the film layer under various focal conditions, it(More)