@incollection{DavinHerder2021, author = {Davin, Till and Herder, Jens}, title = {Real-Time Relighting of Video Streams for Augmented Virtuality Scenes}, series = {GI VR / AR Workshop. Gesellschaft f{\"u}r Informatik e.V.}, booktitle = {GI VR / AR Workshop. Gesellschaft f{\"u}r Informatik e.V.}, editor = {Weier, Martin and Bues, Matthias and Wechner, Reto}, publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)}, address = {Bonn}, doi = {10.18420/vrar2021_6}, publisher = {Hochschule D{\"u}sseldorf}, pages = {16}, year = {2021}, language = {en} } @inproceedings{HonsbrokMostafawyHerderetal.2025, author = {Honsbrok, Jan and Mostafawy, Sina and Herder, Jens and Huldtgren, Alina}, title = {Ray-LUT: A Lookup-Based Method for Camera Lens Simulation in Real-Time Using Ray Tracing}, series = {Proceedings of the 20th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications}, booktitle = {Proceedings of the 20th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications}, publisher = {SciTePress}, doi = {10.5220/0013105900003912}, pages = {177 -- 184}, year = {2025}, abstract = {Lens systems have a major influence on the image due to effects such as depth of field or optical aberrations. The only method to simulate these effects precisely is to trace rays through an actual lens system. This provides accurate results, but only with high computational effort. To speed up the ray tracing through the lens system, various acceleration methods have been developed, requiring considerable precomputations. We present a new method based on the Realistic Camera by Kolb et. al.. Instead of tracing each ray through the lens system, the rays are precomputed once and stored in a lookup table. In contrast to other methods, our method is simple, and does not require substantial preprocessing upfront. We can simulate complex effects such as chromatic aberrations accurately in real-time, regardless the number of lens surfaces in the system. Our method achieves the same performance as state-of-the-art methods like Polynomial Optics, while maintaining the same number of samples per pixel.}, language = {en} } @inproceedings{HerderNeiderKinuwaki2007, author = {Herder, Jens and Neider, Christian and Kinuwaki, Shinichi}, title = {HDR-based lighting estimation for virtual studio (TV) environments}, series = {10th International Conference on Human and Computer}, booktitle = {10th International Conference on Human and Computer}, address = {D{\"u}sseldorf, Aizu-Wakamatsu}, doi = {10.20385/opus4-1666}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-16665}, pages = {111 -- 117}, year = {2007}, abstract = {Two high dynamic range HDR environments maps based on video streams from fish-eye lens cameras are used for generating virtual lights in a virtual set renderer. The task of realistic virtual light setup of scenes using captured environment maps might be eased as well as visual quality improves. We discuss the light setting problem for virtual studio tv productions which have mixed scenes of real objects, actors, virtual objects and virtual backgrounds. Benefits of hdr interactive light control are that the real light in the studio does not have to be remodeled and the artistic impression by using the light in the studio is also captured. An analysis of system requirements identifies technical challenges. We discuss the properties of a prototype system including test production.}, language = {en} } @incollection{MichaelisHerder2025, author = {Michaelis, Maja and Herder, Jens}, title = {Augmented Reality for Lighting Adjustment in a Virtual Studio}, series = {Augmented Reality - Situated Spatial Synergy [Working Title]}, booktitle = {Augmented Reality - Situated Spatial Synergy [Working Title]}, editor = {Cohen, Michael}, publisher = {IntechOpen}, address = {London}, doi = {10.5772/intechopen.1012424}, publisher = {Hochschule D{\"u}sseldorf}, year = {2025}, abstract = {An interactive virtual studio is used for live broadcasts with live interaction in front of the recording system. Advances in Augmented Reality (AR) using video see-through Head-Mounted Displays (HMDs) also make it possible to improve the production process itself. Lighting can be improved and adjusted using AR while seeing live effects. An Augmented Reality Lighting Adjustment System (ARLAS) for a virtual studio has been developed and evaluated. The traditional process for controlling lighting in a virtual studio is complicated and time-consuming. It often requires several people to control many different components at different locations. Using AR, this process is simplified by integrating relevant programs and video streams into a single application on an HMD, allowing direct control at lighting locations. Changes to settings are immediately visible on the real fixtures. Real lights can be replicated virtually to maintain consistent lighting conditions in virtual scenes, ensuring that virtual objects are lit as they would be in a real studio. The prototype demonstrated the benefits of AR for complex virtual studio setups and was evaluated by 18 participants.}, subject = {Erweiterte Realit{\"a}t (Informatik)}, language = {en} }