Vector-raster interoperation: A spatial query language approach

Abstract

Integration of vector and raster has long been a challenge to GIS design. This paper attempts to design a spatial query language called SQL/VecRas to provide an integrated interface for the open access of two major kinds of GIS data: vector and raster. By defining vector and raster data types, and the combined vector-raster functions, the integrated queries involving both vector and raster data sources can be expressed by this language. The combined vector-raster functions are realized by special algorithms so that mutual vector-raster data conversions, adopted in many GIS packages, are not required. The language is implemented by translating it into Avenue scripts under the ArcView environment. It was demonstrated that SQL/VecRas provides a packaged solution to vector-raster interoperation, and reduces the user's interaction significantly. It is hoped that this approach can shed light on the interoperation of other data sources or other interoperation problems.