Cartographic generalisation of lines based on a B‐spline snake model

Abstract

The automation of cartographic map production is still an important research field in Geographical Information Systems (GIS). With the increasing development of monitoring and decision‐aid systems either on computer networks or wireless networks, efficient methods are needed to visualise geographical data while respecting some application constraints (accuracy, legibility, security, etc.). This paper introduces a B‐spline snake model to deal with the current operators involved in the cartographic generalisation process of lines. This model enables us to perform those operators with a continuous approach. In order to avoid local conflicts such as intersections or self‐intersections, the consistency of the lines is checked and discrete operations such as segment removal are performed during the process. We apply the method to map production in the highly constrained domain of maritime navigation systems. Experimental results of marine chart generalisation yield some discussions about generalisation robustness and quality.

Keywords:

• Cartographic generalisation
• B‐spline curve
• Snake
• Contour lines

Acknowledgements

The work described in this paper is supported by Hong Kong RGC Direct Grant for Research C001/2020880. We are grateful to the Oceanographic and Hydrographic Service of the French Navy (Brest, France) for their cartographic data and valuation of the results.