Secure and Fast Urban Visualization

Due to the rising interest in urban visualization, a number of issues have emerged that need to be solved for practical application. The most prominent of these issues are: visualization performance and security. Visualization speed concerns the usability of urban visualization. In order to make urban visualization practical, it is necessary to completely hide all latency of loading data. Here we will demonstrate techniques like multi-threading, different rendering methods and level-of-detail that our platform uses to maintain interactive frame-rates in the face of the large amounts of data that are common in urban visualization environments. The secondissue, securing the geometry and image information contained in an urban model is of eminent importance for the owner of the data. We will point out a number of techniques that have been incorporated in our viewing platform in order to maintain a high level of data security: data compression and encryption, obfuscation of access keys, compression and encryption of executables. While perfect security is an unattainable goal, the multi-staged approach of security in our system significantly raises the cost of illegally obtaining access to the geometry or image data. By demonstrating solutions for both issues our framework serves as a viable platform for urban visualization

The PRoViDE Framework: Accurate 3D geological models for virtual exploration of the Martian surface from rover and orbital imagery

In this chapter, we describe the PRoViDE (Planetary Robotics Vision Data Exploitation) framework that supports an entire workflow to generate 3D geological models of planetary surfaces from separate or fused rover and orbiter imagery, which are used for an efficient and reliable geologic analysis. PRoViDE provides a comprehensive solution for planetary geological studies including tools and data products from multi-resolution co-registered orbital imagery to multi-resolution rover derived imagery. A special processing called Super-Resolution Restoration (SRR) increases the accuracy of some orbital imagery. The main components of PRoViDE consist of a geo-database (PRoDB) to gather and manage huge volumes of data, a prototype of a planetary webGIS (PRoGIS) providing a classical map view, a processing pipeline producing multi-resolution 3D reconstructions of planetary surfaces (PRoViP) and an interactive 3D viewer for virtual exploration and visual analysis (PRo3D). This viewer relies on advanced real-time visualization and interaction methods tailored to geospatial data. Various measurement tools are provided for a quantitative analysis of geological features. In summary, the PRoViDE framework enables an efficient and accurate investigation chain for detailed geologic interpretation of a planetary region, which also serves as decision support for mission planning

Collaborative animation over the network

The continuously increasing complexity of computer animations makes it necessary to rely on the knowledge of various experts to cover the different areas of computer graphics and animation. This fact, which can be noted in many areas of scientific working, leads to increasing effort being put into research concerning cooperative working over the internet. However, it still requires substantialeffort and time to combine different animation techniques in a common virtual environment. When trying to perform collaborative animation over a network, we often face the problem of having to combine animation systems and applications based on different software and hardware and using incompatible data structures. We present an approach, based on a client-server architecture and employing a VRML-based language as common interchange format, that allows inhomogeneous systems to be easily incorporated into a collaborative animation. The applications can be freed from employing plug-ins or libraries to link into a common animation platform; they keep a local copy of the global scene and only need the ability to export the internal data representation into the so called "PaVRML" language, the language we use use to exchange data and synchronize the clients. This approach does not only allow a number of practitioners to share their know-how within a common animation without requiring the huge amount of work necessary to port their application to a common platform. It also makes it often possible in the first place to combine the capabilities of different animation systems into a single complex animation. Additionally, we investigate solutions to optimize the network load for real-time applications. In this paper we present preliminary results and discuss the future developments of thi..