@unpublished{WetzsteinBimber2006, author = {Wetzstein, Gordon and Bimber, Oliver}, title = {A Generalized Approach to Radiometric}, doi = {10.25643/bauhaus-universitaet.762}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-7625}, year = {2006}, abstract = {We propose a novel method that applies the light transport matrix for performing an image-based radiometric compensation which accounts for all possible types of light modulation. For practical application the matrix is decomposed into clusters of mutually influencing projector and camera pixels. The compensation is modeled as a linear system that can be solved with respect to the projector patterns. Precomputing the inverse light transport in combination with an efficient implementation on the GPU makes interactive compensation rates possible. Our generalized method unifies existing approaches that address individual problems. Based on examples, we show that it is possible to project corrected images onto complex surfaces such as an inter-reflecting statuette, glossy wallpaper, or through highly-refractive glass. Furthermore, we illustrate that a side-effect of our approach is an increase in the overall sharpness of defocused projections.}, subject = {Association for Computing Machinery / Special Interest Group on Graphics}, language = {en} } @unpublished{ZollmannBimber2007, author = {Zollmann, Stefanie and Bimber, Oliver}, title = {Imperceptible Calibration for Radiometric Compensation}, doi = {10.25643/bauhaus-universitaet.809}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-8094}, year = {2007}, abstract = {We present a novel multi-step technique for imperceptible geometry and radiometry calibration of projector-camera systems. Our approach can be used to display geometry and color corrected images on non-optimized surfaces at interactive rates while simultaneously performing a series of invisible structured light projections during runtime. It supports disjoint projector-camera configurations, fast and progressive improvements, as well as real-time correction rates of arbitrary graphical content. The calibration is automatically triggered when mis-registrations between camera, projector and surface are detected.}, subject = {Association for Computing Machinery / Special Interest Group on Graphics}, language = {en} } @unpublished{GrundhoeferBimber2006, author = {Grundh{\"o}fer, Anselm and Bimber, Oliver}, title = {Real-Time Adaptive Radiometric Compensation}, doi = {10.25643/bauhaus-universitaet.784}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-7848}, year = {2006}, abstract = {Recent radiometric compensation techniques make it possible to project images onto colored and textured surfaces. This is realized with projector-camera systems by scanning the projection surface on a per-pixel basis. With the captured information, a compensation image is calculated that neutralizes geometric distortions and color blending caused by the underlying surface. As a result, the brightness and the contrast of the input image is reduced compared to a conventional projection onto a white canvas. If the input image is not manipulated in its intensities, the compensation image can contain values that are outside the dynamic range of the projector. They will lead to clipping errors and to visible artifacts on the surface. In this article, we present a novel algorithm that dynamically adjusts the content of the input images before radiometric compensation is carried out. This reduces the perceived visual artifacts while simultaneously preserving a maximum of luminance and contrast. The algorithm is implemented entirely on the GPU and is the first of its kind to run in real-time.}, subject = {Maschinelles Sehen}, language = {en} }