| VTS(Vessel Traffic Services) system is aimed at improving vessel traffic safety, efficiency and protecting seas environment. Its development is to satisfy the increasing requirements caused by the rapid development of waterborne traffic and the rise of vessel density.Radar sub-system is an essential part of VTS system. It can get the information of the objects in its supervised water area by collecting the reflected electromagnetic wave. Because the raw radar video represents the real condition of the supervised water area, it is an important information resource for VTS centers and maritime administrative offices to get the evidence on the spot. But the bandwidth of the raw radar video is too wide to transmit directly in the common communication channel. Therefore, it is necessary to compress the raw radar video before transmission so as to satisfy the channel bandwidth.Furthermore, computer-based technologies have got widely used in this rapidly developing information era. Modern VTS is growing to be a system with uniform abilities to process and represent every kind of information, open system structure, and highly efficient man-machine interactivity.Considering practical needs and developing trend of VTS, based on analyzing the signal characters of VTS radar video, studying basic data compression principles in Information Theory, comparing international coding standards in the forefront of image processing, a VTS radar video coding system suitable for transmission in the narrow channel is proposed in this thesis. Its main block梒oder and decoder, is realized in the common PC with software. The working process is demonstrated detailed. Two coding schemes suitable for compressing radar image are also proposed, one based on JPEG algorithm and the other based on H.263 algorithm. Finally, the simulation is conducted, and the feasibility and practicality are analyzed based on the results of the experiments.
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