Isobathymetric Line Simplification with Conflict Removal Based on a B-spline Snake Model

Abstract

This paper introduces a new method for the smoothing of isobathymetric lines for marine chart construction. Specific constraints have to be observed as the chart must be legible and safe for navigation. The method, based on a snake model, respects these constraints of legibility and safety which impose a direction for curve deformation. Conflicts such as self-intersections are also considered. These two points are the main contributions of the paper as current methods cannot deal with such constraints. Several case studies are presented and results obtained on real data are discussed.

Keywords:

• Cartographic generalization
• B-spline curve
• snakes
• smoothing
• maritime GIS

Acknowledgements

The work described in this paper is supported by RGC Direct Grant for Research C001/2020880. The authors would like to thank Mr. Michel Faramin for his valuable comments.