39 research outputs found
Scene Analysis for Reducing Motion JPEG 2000 video Surveillance Delivery Bandwidth and Complexity
Abstract — In this paper, we propose a new object-based video coding/transmission system using the emerging Motion JPEG 2000 standard [1] for the efficient storage and delivery of video surveillance over low bandwidth channels. Some recent papers deal with JPEG 2000 coding/transmission based on the Region Of Interest (ROI) feature and the multi-layer capability provided by this coding system [2][3]. Those approaches allow delivering more quality for mobile objects (or ROI) than for the background when bandwidth is too narrow for a sufficient video quality. The method proposed here provides the same features while significantly improving the average bitrate/quality ratio of delivered video when cameras are static. We transmit only ROIs of each frame as well as an automatic estimation of the background at a lower frame rate in two separate Motion JPEG 2000 streams. The frames are then reconstructed at the client side without the need of other external data. Our method provides both better video quality and reduced client CPU usage with negligible storage overhead. Video surveillance streams stored on the server are fully compliant with existing Motion JPEG 2000 decoders
Nisin-induced changes in Bacillus morphology suggest a paradigm of antibiotic action
International audienc
Biomarkers and Tracers of Atmospheric Evolution of Exoplanets In The Spectroscopic Window of Darwin
International audienc
Biomarkers and Tracers of Atmospheric Evolution of Exoplanets In The Spectroscopic Window of Darwin
International audienc
Software Radio Spectrum Analyzer
International audienceThis paper presents the implementation of a software radio spectrum analyzer using USRP platforms form Ettus Research as a frequency translator and Simulink environment for baseband processing. The algorithms that are used and the performance that are obtained are detailed. This work can be used as a pedagogic tool. It also illustrates that software radio is not only restricted to communication devices. Moreover, it gives insight on the performance bottlenecks of a software defined radio approach mixing hardware and software considerations, especially on the software environment aspects (operating system and software environment)
Biomarkers and Tracers of Atmospheric Evolution of Exoplanets In The Spectroscopic Window of Darwin
International audienc
Infrared laboratory tests of the 4-quadrant coronograph MIRI/JWST and VLT-PF
International audienc
Infrared laboratory tests of the 4-quadrant coronograph MIRI/JWST and VLT-PF
International audienc
A flexible video transmission system based on JPEG 2000 conditional replenishment with multiple references
The image compression standard JPEG 2000 offers a high compression efficiency a well as a great flexibility in the way it accesses the content in terms of spatial location, quality level, and resolution. This paper explores how transmission systems conveying video surveillance sequences can benefit from this flexibility. Rather than transmitting each frame independently as it is generally done in the literature for JPEG 2000 based systems, we adopt a conditional replenishment scheme to exploit the temporal correlation of the video sequence. As a first contribution, we propose a rate-distortion optimal strategy to select the most profitable packets to transmit. As a second contribution, we provide the client with two references, the previous reconstructed frame and an estimation of the current scene background, which improves the transmission system performances