Dominik Rosenbaum

An Operational System for Estimating Road Traffic Information from Aerial Images

Given that ground stationary infrastructures for traffic monitoring are barely able to handle everyday traffic volumes, there is a risk that they could fail altogether in situations arising from mass events or disasters. In this work, we present an alternative approach for traffic monitoring during disaster and mass events, which is based on an airborne optical sensor system. With this system, optical image sequences are automatically examined on board an aircraft to estimate road traffic information, such as vehicle positions, velocities and driving directions. The traffic information, estimated in real time on board, is immediately downlinked to a ground station. The airborne sensor system consists of a three-head camera system, a real-time-capable GPS/INS unit, five industrial PCs and a downlink unit. The processing chain for automatic extraction of traffic information contains modules for the synchronization of image and navigation data streams, orthorectification and vehicle detection and tracking modules. The vehicle detector is based on a combination of AdaBoost and support vector machine classifiers. Vehicle tracking relies on shape-based matching operators. The processing chain is evaluated on a large number of image sequences recorded during several campaigns, and the data quality is compared to that obtained from induction loops. In summary, we can conclude that the achieved overall quality of the traffic data extracted by the airborne system is in the range of 68% and 81%. Thus, it is comparable to data obtained from stationary ground sensor networks.

Low-cost optical Camera System for real-time Mapping Applications

Die Beobachtung von Naturkatastrophen, Grosereignissen und Unfallen mit flugzeuggestutzten optischen Sensoren in Echtzeit ist ein derzeit wichtiges Thema in Forschung und Entwicklung. In diesem Zusammenhang wird die Leistungsfahigkeit von preisgunstigen Kamerasystemen fur Echtzeitanwendungen in Hinblick auf geometrische Genauigkeit, radiometrische Eigenschaften und Prozessierungszeiten evaluiert. Der Schwerpunkt liegt bei der Analyse der geometrischen Stabilitat von preisgunstigen Kameras im langjahrigen Betrieb und den Grenzen der direkten Georeferenzierung. Weiterhin wird eine echtzeitfahige Prozessierungskette mit einer GPU (Graphical Processing Unit) basierten Orthorektifizierungsmethode fur eine maximal mogliche Aufnahmerate von 5Hz vorgestellt.

A new software/hardware architecture for real time image processing of wide area airborne camera images

This paper describes a new software/hardware architecture for processing wide area airborne camera images in real time. The images under consideration are acquired from the 3K-camera system developed at DLR (German Aerospace Center). It consists of three off-the-shelf cameras, each of it delivers 16 Mpixel three times a second. One camera is installed in nadir, whereas the other two cameras are looking in side direction. Main applications of our system are supposed to be automotive traffic monitoring, determining the workload of public road networks during mass events, or obtaining a survey of damages in disaster areas in real time. Altogether, this demands a fast image processing system on the aircraft, because the amount of original high resolution images can not be sent to ground by up-to-date transfer mode systems. The on-board image processing system is distributed over a local network. On each PC several modules are running concurrently. In order to synchronize several processes and to assure access to commonly used data, a new distributed middleware for real time image processing is introduced. Two sophisticated modules one for orthorectification of images and one for traffic monitoring are explained in more detail. The orthorectification and mosaicking is executed on the fast graphics processing unit on one PC, whereas the traffic monitoring module runs on another PC in the on-board network. The resulting image data and evaluated traffic parameters are sent to a ground station in near real time and are distributed to the involved users. Thus, with the here suggested software/hardware system it becomes possible to support rescue forces and security forces in disaster areas or during mass events in near real time.

Analysis of Image Sequences for the Detection and Monitoring of Moving Traffic

Analyse von Bildsequenzen zur Detektion und Uberwachung von fliesendem Verkehr. Dieser Artikel zielt auf das Erkennen und Verfolgen von Fahrzeugen aus luftgetragenen Bildsequenzen zur Uberwachung von fliesendem Verkehr. Zwei unterschiedliche Systeme werden beschrieben: Das Erste ist ein echtzeitnahes Tracking- Verfahren, welches auf der normalisierten Kreuzkorrelation basiert. Das zweite Verfahren bindet Modellwissen uber Fahrerverhalten, Verkehrsdynamiken und Kontext ein, um Geschwindigkeitsund Trajektorienbewertungen auszunutzen. Die Ergebnisse und die abgeleiteten Qualitatsmase zeigen die Leistungsfahigkeit der Systeme, insbesondere der Beitrag des Verkehrsmodellwissens erhoht die Korrektheit der Trackingergebnisse. Abschliesend wird ein Ausblick auf zukunftige Forschungen gegeben.

CHICAGO – An Airborne Observation System for Security Applications

The paper describes the layout of a new research aircraft for security applications. The typical applications for such an aircraft are outlined and the system requirements are derived. Furthermore, the performance of the system and a first mission is described.