Volume II-2
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., II-2, 1-7, 2014
https://doi.org/10.5194/isprsannals-II-2-1-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., II-2, 1-7, 2014
https://doi.org/10.5194/isprsannals-II-2-1-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.

  11 Nov 2014

11 Nov 2014

An ontology for the generalisation of the bathymetry on nautical charts

J. Yan1,2, E. Guilbert3, and E. Saux1 J. Yan et al.
  • 1Institut de Recherche de l’École Navale, GIS group, Lanvéoc-Poulmic, CC600, 29240 Brest Cedex 9, France
  • 3Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
  • 2Département des Sciences Géomatiques, Pavillon Louis-Jacques-Casault, Université Laval, Québec (Québec) G1V 0A6, Canada

Keywords: Cartography, Bathymetry, Generalization, Representation, DEM/DTM

Abstract. On nautical charts, undersea features are portrayed by sets of soundings (depth points) and isobaths (depth contours) from which map readers can interpret landforms. Different techniques were developed for automatic soundings selection and isobath generalisation from a sounding set. These methods are mainly used to generate a new chart from the bathymetric database or from a large scale chart through selection and simplification however a part of the process consists in selecting and emphasising undersea features on the chart according to their relevance to navigation. Its automation requires classification of the features from the set of isobaths and soundings and their generalisation through the selection and application of a set of operators according not only to geometrical constraints but also to semantic constraints.

The objective of this paper is to define an ontology formalising undersea feature representation and the generalisation process achieving this representation on a nautical chart. The ontology is built in two parts addressing on one hand the definition of the features and on the other hand their generalisation. The central concept is the undersea feature around which other concepts are organised. The generalisation process is driven by the features where the objective is to select or emphasise information according to their meaning for a specific purpose. The ontologies were developed in Protégé and a bathymetric database server integrating the ontology was implemented. A generalisation platform was also developed and examples of representations obtained by the platform are presented. Finally, current results and on-going research are discussed.