| Voyage Data Recorder is a kind of intelligent system that can record, save and analyze the information concerning voyage of ships. The functions of VDR are similar with those of aeronautical Black-box. The information recorded is useful to arbitrate the reasons and responsibilities of maritime affairs. Radar image acquisition module of VDR system is designed to record radar images of vessels, which will be compressed and saved on Flash. The resolution of radar image can obtain 1280 by 1024, and the period of acquisition is 15 seconds per frame.The Fractal theory is a very active branch of modern mathematics and non-linear theory. In the last decade, it has played an increasingly important role in image processing. There are wide applications of Fractal theory in the fields, such as image compression, natural image simulation, image texture analysis, pattern recognition and so on. Fractal image compression is a novel technology. Especially, Fractal image compression technology surpasses the limitation of traditional coding method and potent larger compression ratio. Although in theory Fractal image coding has great advantages, practically, the research on it is on the beginning stage.This paper presents a review on the development of VDR and Fractal theory, and introduces the knowledge about Fractal compression method briefly. Some basic mathematic theories about the Fractal image compression coding are given. The main problems that exist in the Fractal compression coding are brought into focus. The advantages and disadvantages of these methods are comprehensively analyzed. The paper uses fractal theory to compress VDR radar image and obtains some meaningful results, including:Firstly, gives a comprehensive introduction to Voyage Date Recorder.Secondly, analyzes the knowledge related to Fractal theory.Thirdly, incorporates Fractal theory into the image compression algorithm, and...
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