The use of different media in visualizing spatial data

Abstract Multimedia technology changes the visualization of spatial data. The map, the traditional presentation of spatial data, is complemented by other media like pictures, animation, sound and video. Each of these additional media has particular abilities to communicate information. For instance some media are suitable to give a vivid picture about a phenomenon and others, on the contrary, are efficient to mediate the idea of spatial concepts. The selection and combination of different media for data visualization in cartography and geosciences have to be guided by two different aspects: by the particular function a medium has to fulfil in a multimedia presentation and by the application context. The functions of media can be derived from human cognition process and from communication purpose. Cognition process explains how media may support perception and cognition. Communication purpose determines what type of media are suitable. The application context of a multimedia presentation is either visual thinking, the graphical exploration or verification of spatial data by an expert or visual communication, the demonstration of spatial data for non-experts. In the first case media have to assist the scientist in finding questions from unstructured data sets and in verifying a derived hypothesis; in the second case media have to present information in a way that people without great knowledge of a subject can perceive and understand that subject. The media design for visual thinking and visual communication have to regard the media functions which were derived from cognition process and communication purpose.