@inproceedings{AytenHerderVonolfen2010, author = {Ayten, H{\"u}seyin and Herder, Jens and Vonolfen, Wolfgang}, title = {Visual Acceptance Evaluation of Soft Shadow Algorithms for Virtual TV Studios}, series = {HC '10 Proceedings of the 13th International Conference on Humans and Computers}, booktitle = {HC '10 Proceedings of the 13th International Conference on Humans and Computers}, publisher = {University of Aizu Press}, address = {Aizu-Wakamatsu}, pages = {66 -- 71}, year = {2010}, abstract = {Shadows in computer graphics are an important rendering aspect for spatial objects. For realtime computer applications such as games, it is essential to represent shadows as accurate as possible. Also, various tv stations work with virtual studio systems instead of real studio sets. Especially for those systems, a realistic impression of the rendered and mixed scene is important. One challenge, hence, is the creation of a natural shadow impression. This paper presents the results of an empirical study to compare the performance and quality of different shadow mapping methods. For this test, a prototype studio renderer was developed. A percentage closer filter (pcf) with a number of specific resolutions is used to minimize the aliasing issue. More advanced algorithms which generate smooth shadows like the percentage closer soft shadow (pcss) method as well as the variance shadow maps (vsm) method are analysed. Different open source apis are used to develop the virtual studio renderer, giving the benefit of permanent enhancement. The Ogre 3D graphic engine is used to implement the rendering system, benefiting from various functions and plugins. The transmission of the tracking data is accomplished with the vrpn server/client and the Intersense api. The different shadow algorithms are compared in a virtual studio environment which also casts real shadows and thus gives a chance for a direct comparison throughout the empirical user study. The performance is measured in frames per secon}, language = {en} } @inproceedings{FlaskoPogschebaHerderetal.2011, author = {Flasko, Matthias and Pogscheba, Patrick and Herder, Jens and Vonolfen, Wolfgang}, title = {Heterogeneous binocular camera-tracking in a Virtual Studio}, series = {8. Workshop Virtuelle und Erweiterte Realit{\"a}t der GI-Fachgruppe VR/AR}, booktitle = {8. Workshop Virtuelle und Erweiterte Realit{\"a}t der GI-Fachgruppe VR/AR}, address = {Wedel}, year = {2011}, abstract = {This paper presents a tracking of parts of a human body in a virtual TV studio environment. The tracking is based on a depth camera and a HD studio camera and aims at a realistic interaction between the actor and the computer generated environment. Stereo calibration methods are used to match corresponding pixels of both cameras (HD color and depth image). Hence the images were rectified and column aligned. The disparity is used to correct the depth image pixel by pixel. This image registration results in row and column aligned images where ghost regions are in the depth image resulting from occlusion. Both images are used to generate foreground masks with chroma and depth keying. The color image is taken for skin color segmentation to determine and distinguish the actor's hands and face. In the depth image the flesh colored regions were used to determine their spatial position. The extracted positions were augmented by virtual objects. The scene is rendered correctly with virtual camera parameters which were calculated from the camera calibration parameters. Generated computer graphics with alpha value are combined with the HD color images. This compositing shows interaction with augmented objects for verification. The additional depth information results in changing the size of objects next to the hands when the actor moves around.}, language = {en} } @inproceedings{HerderVonolfenGriesertetal.2004, author = {Herder, Jens and Vonolfen, Wolfgang and Griesert, Arnfried and Heuer, Stefan and Hoffmann, Ansgar and H{\"o}ppner, Bernd}, title = {Interactive Virtual Set Applications for Post Production}, series = {University of Aizu 2004 - Seventh International Conference on Human}, booktitle = {University of Aizu 2004 - Seventh International Conference on Human}, address = {Aizu-Wakamatsu}, year = {2004}, abstract = {Virtual set environments for broadcasting become more sophisticated as well as the visual quality improves. Realtime interaction and production-specific visualization implemented through plugin mechanism enhance the existing systems like the 3DK. This work presents the integration of the Intersense IS-900 SCT camera tracking and 3D interaction into the 3DK virtual studio environment. The main goal of this work is the design of a virtual studio environment for post productions, which includes video output as well as media streaming formats such as MPEG-4. The systems allows high quality offline rendering during post production and 3D interaction by the moderator during the recording.}, language = {en} } @inproceedings{KlapdohrWoeldeckeMarinosetal.2010, author = {Klapdohr, Monika and W{\"o}ldecke, Bj{\"o}rn and Marinos, Dionysios and Herder, Jens and Geiger, Christian and Vonolfen, Wolfgang}, title = {Vibrotactile Pitfalls: Arm Guidance for Moderators in Virtual TV Studios}, series = {HC '10 Proceedings of the 13th International Conference on Humans and Computers}, booktitle = {HC '10 Proceedings of the 13th International Conference on Humans and Computers}, publisher = {University of Aizu Press}, address = {Aizu-Wakamatsu}, pages = {72 -- 80}, year = {2010}, abstract = {For this study, an experimental vibrotactile feedback system was developed to help actors with the task of moving their arm to a certain place in a virtual tv studio under live conditions. Our intention is to improve interaction with virtual objects in a virtual set, which are usually not directly visible to the actor, but only on distant displays. Vibrotactile feedback might improve the appearance on tv because an actor is able to look in any desired direction (camera or virtual object) or to read text on a teleprompter while interacting with a virtual object. Visual feedback in a virtual studio lacks spatial relation to the actor, which impedes the adjustment of the desired interaction. The five tactors of the implemented system which are mounted on the tracked arm give additional information like collision, navigation and activation. The user study for the developed system shows that the duration for reaching a certain target is much longer in case no visual feedback is given, but the accuracy is similar. In this study, subjects reported that an activation signal indicating the arrival at the target of a drag \& drop task was helpful. In this paper, we discuss the problems we encountered while developing such a vibrotactile display. Keeping these pitfalls in mind could lead to better feedback systems for actors in virtual studio environments.}, language = {en} } @inproceedings{LudwigBuechelHerderetal.2012, author = {Ludwig, Philipp and B{\"u}chel, Joachim and Herder, Jens and Vonolfen, Wolfgang}, title = {InEarGuide - A Navigation and Interaction Feedback System using In Ear Headphones for Virtual TV Studio Productions}, series = {9. Workshop Virtuelle und Erweiterte Realit{\"a}t der GI-Fachgruppe VR/AR}, booktitle = {9. Workshop Virtuelle und Erweiterte Realit{\"a}t der GI-Fachgruppe VR/AR}, address = {D{\"u}sseldorf}, year = {2012}, abstract = {This paper presents an approach to integrate non-visual user feedback in today's virtual tv studio productions. Since recent studies showed that systems providing vibro-tactile feedback are not sufficient for replacing the common visual feedback, we developed an audio-based solution using an in ear headphone system, enabling a talent to move, avoid and point to virtual objects in a blue or green box. The system consists of an optical head tracking system, a wireless in ear monitor system and a workstation, which performs all application and audio processing. Using head related transfer functions, the talent gets directional and distance cues. Past research showed, that generating reflections of the sounds and simulating the acoustics of the virtual room helps the listener to conceive the acoustical feedback, we included this technique as well. In a user study with 15 participants the performance of the system was evaluated.}, language = {en} }