Specialized knowledge in visualization software packages such as Visualization Toolkit (VTK), Generic Mapping Tools (GMT), and NCAR Command Language (NCL) is almost always a requisite for writ- ing applications that visualize datasets or information. Technical under- standing of visualization packages including rendering capabilities and data format ingestion is needed before it can be determined whether a package can satisfy some set of visualization requirements. Even after identification of satisfactory visualization packages, an application must still be built on packages that generate the required visualizations. Visualization Knowledge (VisKo) modularized ontology set encodes knowledge about visualization software packages using semantic Web technologies (e.g., RDF, OWL, and Pellet) in order to facilitate the scientist task of visualizing data and information. In the presence of VisKo, users may move away from writing visualization applications and move towards an environment where they can request for visualizations declaratively and without being fully aware of a wide range of visualization package implementation details.
The use of VisKo ontologies is supported by a fully implemented environment composed of a query language, a visualization knowledge base, and a set of visualization services. The VisKo ontology and supporting environment has been in use by many scientific initiatives including visualizing artifacts associated with a seismic tomography, gravity anomalies, and brightness temperature.