Abstract: The large size is a typical feature of earth observation images. The increasing number of bands simultaneously available on satellites and the launch of system able to achieve a ground resolution as low as one meter is making this problem more a nd more hot. Indeed, the large size of typical images dramatically reduces the possibility to distribute them to a wide number of interest parties. In the wide majority of cases, this problem is currently tackled either by using lossy compression schemes such as basic versions of JPEG or by narrowing the ground extension of the pictures. Of course, both of them are unsatisfactory. Indeed, the partial loss of data may be acceptable only for non-quantitative analysis while narrower pictures may not carry all the needed informant. An alternate possibility is the use of an efficient lossless algorithm. Among others, JBIG has been preferred for this purpose because it achieves very high compression rate, overperforming the well known ZIP algorithm in the wide majority of cases. Further advantages are due to its progressive nature and to its availability as an ITU international standard. In order to have a very performant syste, this algorithm has been implemented by the development of an application specific integrated circuit designed to compress/decompress large volumes of data with throughput rate greater than 1 Gb/min. The performances achieved by the system when dealing with typical visual and radar satellite images and the perspective applications are described. !3
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