@techreport{AmanoBimberGrundhoefer2010, author = {Amano, Toshiyuki and Bimber, Oliver and Grundh{\"o}fer, Anselm}, title = {Appearance Enhancement for Visually Impaired with Projector Camera Feedback}, doi = {10.25643/bauhaus-universitaet.1411}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20100106-14974}, year = {2010}, abstract = {Visually impaired is a common problem for human life in the world wide. The projector-based AR technique has ability to change appearance of real object, and it can help to improve visibility for visually impaired. We propose a new framework for the appearance enhancement with the projector camera system that employed model predictive controller. This framework enables arbitrary image processing such as photo-retouch software in the real world and it helps to improve visibility for visually impaired. In this article, we show the appearance enhancement result of Peli's method and Wolffshon's method for the low vision, Jefferson's method for color vision deficiencies. Through experiment results, the potential of our method to enhance the appearance for visually impaired was confirmed as same as appearance enhancement for the digital image and television viewing.}, subject = {Maschinelles Sehen}, language = {en} } @techreport{GrundhoeferBimber2008, author = {Grundh{\"o}fer, Anselm and Bimber, Oliver}, title = {Dynamic Bluescreens}, doi = {10.25643/bauhaus-universitaet.1233}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20080226-13016}, year = {2008}, abstract = {Blue screens and chroma keying technology are essential for digital video composition. Professional studios apply tracking technology to record the camera path for perspective augmentations of the original video footage. Although this technology is well established, it does not offer a great deal of flexibility. For shootings at non-studio sets, physical blue screens might have to be installed, or parts have to be recorded in a studio separately. We present a simple and flexible way of projecting corrected keying colors onto arbitrary diffuse surfaces using synchronized projectors and radiometric compensation. Thereby, the reflectance of the underlying real surface is neutralized. A temporal multiplexing between projection and flash illumination allows capturing the fully lit scene, while still being able to key the foreground objects. In addition, we embed spatial codes into the projected key image to enable the tracking of the camera. Furthermore, the reconstruction of the scene geometry is implicitly supported.}, subject = {Association for Computing Machinery / Special Interest Group on Graphics}, language = {en} } @techreport{ExnerBrunsKurzetal.2009, author = {Exner, David and Bruns, Erich and Kurz, Daniel and Grundh{\"o}fer, Anselm and Bimber, Oliver}, title = {Fast and Reliable CAMShift Tracking}, organization = {JP AUgmented Reality, Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.1410}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20091217-14962}, year = {2009}, abstract = {CAMShift is a well-established and fundamental algorithm for kernel-based visual object tracking. While it performs well with objects that have a simple and constant appearance, it is not robust in more complex cases. As it solely relies on back projected probabilities it can fail in cases when the object's appearance changes (e.g. due to object or camera movement, or due to lighting changes), when similarly colored objects have to be re-detected or when they cross their trajectories. We propose extensions to CAMShift that address and resolve all of these problems. They allow the accumulation of multiple histograms to model more complex object appearance and the continuous monitoring of object identi- ties to handle ambiguous cases of partial or full occlusion. Most steps of our method are carried out on the GPU for achieving real-time tracking of multiple targets simultaneously. We explain an ecient GPU implementations of histogram generation, probability back projection, im- age moments computations, and histogram intersection. All of these techniques make full use of a GPU's high parallelization.}, subject = {Bildverarbeitung}, language = {en} } @techreport{GrundhoeferSeegerHaentschetal.2007, author = {Grundh{\"o}fer, Anselm and Seeger, Manja and H{\"a}ntsch, Ferry and Bimber, Oliver}, title = {Dynamic Adaptation of Projected Imperceptible Codes}, doi = {10.25643/bauhaus-universitaet.816}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-8168}, year = {2007}, abstract = {In this paper we present a novel adaptive imperceptible pattern projection technique that considers parameters of human visual perception. A coded image that is invisible for human observers is temporally integrated into the projected image, but can be reconstructed by a synchronized camera. The embedded code is dynamically adjusted on the fly to guarantee its non-perceivability and to adapt it to the current camera pose. Linked with real-time flash keying, for instance, this enables in-shot optical tracking using a dynamic multi-resolution marker technique. A sample prototype is realized that demonstrates the application of our method in the context of augmentations in television studios.}, subject = {Association for Computing Machinery / Special Interest Group on Graphics}, language = {en} }