Fast Updating National Geo-Spatial Databases with High Resolution Imagery: China's Methodology and Experience

Abstract

ABSTRACT:Geospatial databases are irreplaceable national treasure of immense importance. Their up-to-dateness referring to its consistency with respect to the real world plays a critical role in its value and applications. The continuous updating of map databases at 1:50,000 scales is a massive and difficult task for larger countries of the size of more than several million's kilometer squares. This paper presents the research and technological development to support the national map updating at 1:50,000 scales in China, including the development of updating models and methods, production tools and systems for large-scale and rapid updating, as well as the design and implementation of the continuous updating workflow. The use of many data sources and the integration of these data to form a high accuracy, quality checked product were required. It had in turn required up to date techniques of image matching, semantic integration, generalization, data base management and conflict resolution. Design and develop specific software tools and packages to support the large-scale updating production with high resolution imagery and large-scale data generalization, such as map generalization, GIS-supported change interpretation from imagery, DEM interpolation, image matching-based orthophoto generation, data control at different levels. A national 1:50,000 databases updating strategy and its production workflow were designed, including a full coverage updating pattern characterized by all element topographic data modeling, change detection in all related areas, and whole process data quality controlling, a series of technical production specifications, and a network of updating production units in different geographic places in the country.

Application of semi-automated settlement detection for an integrated topographic map information system update in South Africa

“…Chen et al, (2014) concur highlighting the importance of topographic information applications for different government agencies, non-governmental organisation, private sector and citizens at large.…”

Information from imagery: ISPRS scientific vision and research agenda

“…At the national level, rapid updating of geospatial databases has become a top priority of national mapping agencies (Heipke et al 2008;Chen et al 2014b). A recent survey conducted by ISPRS with the help of the United Nations Global Geospatial Information Management group (UN-GGIM) shows that some UN member states update their geospatial databases once per year and many other countries have succeeded in completing or updating their mapping requirements at the critical scales 1:5000 to 1:50 000 (Konecny 2013).…”