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Storage of multi-component digital maps using JBIG2 image compression standard

Digital maps can be stored and distributed electronically using compressed raster image formats. Spatial access must be implemented to enable the user to operate directly on the compressed data without retrieving the entire image. In this work, we study how the latest JBIG2 standard can be used for storing the map images. The image tiling can be supported quite easily by storing each image block as its own segment. A slightly more difficult problem is how to store the multiple image components because the standard does not have any direct support for it. There are alternative ways to overcome this problem by utilizing the features of JBIG2 in creative ways. We show by experimental results that the block division of 128×128 can be implemented with about 15-30 % overhead.