Spatial queries on compressed raster images How to get the best of both worlds

Content Provider	Semantic Scholar
Author	Pajarola, Renato Widmayer, Peter
Copyright Year	1995
Abstract	The maintenance of large raster images such as satellite pictures in geographic infor mation systems is still a major performance bottleneck For reasons of storage space images in a collection are maintained in compressed form An operation on an image can be performed by rst decompressing the compressed version This however can be a major source of ine ciency because the entire image needs to be accessed even though a small part of it might su ce to answer the query We propose to perform spatial queries directly on the compressed version of the im age With current compression algorithms this cannot be done e ciently We therefore propose a new compression technique that allows for the subsequent use of a spatial data structure to guide a search In response to a range query our algorithm delivers a com pressed partial image this response may be sent over a network as it is or it may be decompressed for further processing We have implemented the new algorithm and we have compared it with standard and sophisticated compression algorithms that do not support spatial operations Our performance evaluation with satellite images shows that the new algorithm not only supports spatial queries but is also competitive in terms of the compression that it achieves
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://www.research-collection.ethz.ch/bitstream/handle/20.500.11850/69288/eth-3332-01.pdf?isAllowed=y&sequence=1
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article