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Compression of map images using code book method

Map images are widely used in variety applications such as personal navigation, mobile computing, internet and academia. The usage of raster maps in many applications especially in small storage devices has negative impacts because of its relatively large size. The efficient use of compression method is essential to meet such requirements. A fast lossless compression scheme for raster map images is proposed in this paper. The proposed scheme is a combination of two methods, Code book construction based on indexing and Row-Column Reduction coding Algorithm. The code book based on indexing is constructed from the similar blocks present in the map image and row column reduction coding algorithm is used to compress the unique blocks in the image. Our experimental results show that the proposed compression scheme has better performance and the scheme is simple and fast.