WEB-BASED SPATIAL DATA QUALITY VISUALISATION: CONCEPTS AND IMPLEMENTATION

摘要

With the help of Internet techniques, spatial data has been used by a variety of users for a wide range of applications. However, many spatial data users are non-experts, who rely on metadata attached to the spatial data to assist their understanding and usage. This requires that the presentation of the metadata should be informative and easy to understand. Although at present there are some metadata standards available in the world and metadata is routinely documented with the spatial data, the current metadata presentation via the Internet still has some defects, especially in the area of data quality. It is indispensable to enrich the data quality presentation for spatial products via the Internet, providing users with more capabilities so that they can decide on data fitness for specific applications more confidently. This paper describes a prototype system aiming to combine visualisation functionality with web-based spatial data quality information, which allows users to browse and analyse positional accuracy for vector data at the feature level in a visible way. Concepts of spatial data quality visualisation are introduced. The process of implementing such an interactive visualisation system for vector data positional accuracy using Scalable Vector Graphics (SVG) is discussed.