Abstract: Chroma Key is a special-effects technique widely used by television and motion picture industries for image composition. This technique allows users to replace sections identified by a chosen colour in a multimedia stream (like a video or a photo) with another image or video stream. In this paper, we describe an easy-to-implement technique for the creation of an Android based application for mobile devices (like smartphones and tablets) that applies Chroma Key-based effects to the video stream coming from the device camera. We discuss the algorithm used to achieve the Chroma Key effect focusing on the computational performance and on the quality of its final result. Using a picture selected from the device gallery, this application makes possible the replacement of video stream background areas characterized by a chroma value with the chosen picture.
Authors: F. Corda, F. Sorrentino, R. Scateni.
CHROMAGRAM: A Real-time Chroma Key Application for Mobile Devices.
EuroGraphics Italian Chapter 2014 (short papers), 49-52.
Cagliari, Italia, Settembre 2014.
Abstract: Navigation systems allow to discover cities and their urban areas easily and quickly, finding the shortest path to reach them and giving directions to users saving their time and energy. At present time, these systems are based over streets maps offered by the major mapping services like Tele Atlas, Navteq or OpenStreetMap. In recent years, thanks to the Google StreetView service it has been possible to discover main cities locations both indoor and outdoor. What is missing in this frame is the possibility to map small urban areas of small and medium sized cities, due to their lack of relevance for the big players. In this cities there could be very interesting areas for tourists. Example locations could be botanical gardens, archeological sites, protected natural areas among others. In this work we tried to set up a navigation system for limited extensions inside urban areas which permits to wander around and gives access to related information using augmented reality techniques. Due to the possible poor wireless coverage in these locations we designed an application that stores all required data on the user’s device, splitting the information in packages according to the chosen language. A key issue was to achieve good results combining all these features in a single device with a small display, overwhelming the constraints due to the mobile environment.
Abstract: We report on an alternative OCGM interface for a bulletin board, where a user can pin a note or a drawing, and actually shares contents. Exploiting direct and continuous manipulations, opposite to discrete gestures, to explore containers, the proposed interface supports a more natural and immediate interaction. It manages also the presence of different simultaneous users, allowing for the creation of local multimedia contents, the connection to social networks, providing a suitable working environment for cooperative and collaborative tasks in a multi-touch setup, such as touch-tables, interactive walls or multimedia boards.
Abstract: The wide availability of low-cost sensing devices is opening the possibility to easily create different interaction settings, which exploit various techniques for a more natural interaction, especially in public and shared settings. In this paper, we compared two different solutions for enhancing the interaction experience of a planetarium application, both replicable at a reasonable cost. The first version is based on a simple multitouch paradigm, while the second one exploits a full-body interaction together with a projection on geodetic sphere. We detail the technical implementation of both versions and, in addition, we discuss the results of user-study that compared the two modalities, which highlights a tradeoff between the control and the users’ involvement in the virtual environment.
Abstract: We present here the ?rst release of an SDK (Software Development Kit) for mobile devices supporting the animation of 3D talking heads: THAL-k. The SDK is constantly evolving and here we discuss the features of version 1.0. This library is thought as a support for all the developers wishing to build applications on smartphones or tablets including avatars to enhance the interaction functionalities. The main challenge we face is to provide developers with a complete SDK for the creation, customization and real-time animation of the models.