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An HTML demo page, based on the results of a collaboration between CRS4 and CSP, is presented explaining some image processing of meteorogical data. Raw data, obtained every 30 minutes from the METEOSAT satellite, is processed to obtain colored high-contrast images, multiple images are then compressed using the MPEG video standard. The HTML page explains the details of the transformation process and contains links to sample images and the CRS4 MPEG wheather movies archive.

Shot Change Detection (SCD) in MPEG coded videos is a complex and still open research problem whose interest is growing up more and more due to the diffusion of Video Databases and Digital Libraries. Techniques providing fully satisfactory performances on complex video domains are not yet available even if a number of proposals exist; such proposals show very often to be complementary in their results. In this context, the Authors investigated the use of Multi-Expert Systems (MES) for approaching the SCD problem. In the present paper, we propose and discuss a strategy to select the SCD techniques to be combined and a method for choosing an effective combining rule. In order to assess the performance of the proposed MES, we set up a database that is significantly wider than the ones commonly used in the field. Experimental results demonstrate that the proposed system performs better than each of the single SCD technique considered.

A high-performance versatile motion estimation processor with regular hardware and control structure capable of MP@HL is presented. It can compute 1920 × 1080 pels in 4096 cycles within search point range 64 with eight identical processors. The presented processor has 100% hardware utilization by eliminating the computation delay between stages, and the capability to compute half pel precision motion estimation. Also, by enhancing image data reuse, the I/O bottleneck problem is alleviated. With efficient scalability, the amount of hardware and computation speed can be easily adjusted for a variety of application areas. The proposed edge effect hardware can be used for object-based coding for MPEG-4. The processor was verified with C++ and VHDL based on actual image data and implemented with 0.6μm gate array. Also, a motion estimator system with image memories and PC host interface was designed.

Distance learning programs use on-line video records to deliver pre-recorded lectures. And, video communication systems can be used as a discussion tool. In this paper, we start our discussion on a multimedia presentation recording system which we had developed. We then present how the video recording concept can be further extended to realize an augmented video conferencing system, which can be used as a peer-to-peer discussion tool, as well as a lecture broadcasting system. We also point out that an object tracking technology can be further integrated to enhance the tool, to enable a more realistic and useful system for the discussion in distance education.

This paper presents a stereoscopic video compression scheme using a novel fast affine motion estimation technique. A temporal scalable approach is used to achieve backward compatibility with a standard definition TV. We use an adaptive mode selection scheme from three temporal locations in both channels. Both block-based and affine-motion based approaches are used to achieve two levels of improvements with different complexities. An innovative motion estimation technique using Gauss–Newton optimization and pyramid processing is implemented to efficiently estimate affine parameters. Unlike other Gauss–Newton approaches, our search technique uses only addition, subtraction and multiplication and it converges within four iterations, which implies great complexity reduction. An efficient and robust affine motion prediction yields significant over the disparity-based approach. Part of the disparity-based approach has been tested in the rigorous MPEG-2 bitstream exchange process, and adopted in the MPEG-2 Multi-View Profile (MVP).