Modelling Spatial Video as part of a GIS Video Analysis Framework

摘要

It is now common for video; real-time and collected, mobile and static, to be georeferenced and stored in large archives for users of expert systems to access and interact with. In the ground-based terrestrial context georeferenced video is also becoming more commonly collected from Mobile Mapping Systems (MMS) in recent years. However, significant problems exist for access to large volumes of archived georeferenced MMS video data in a GIS context. These include the semantics behind the modelling of its spatial content and the development of a computationally efficient query model that can isolate video sequences of geographical interest. These specific problems highlight a core difficulty when a geographical based video access query is required. Firstly, how can an optimised model of the video's spatial content be defined and, secondly, how can this spatial model be used to generate a meaningful spatial result. This paper outlines a georeferenced-video framework where a GIS-viewshed oriented approach to modelling and querying terrestrial mobile imagery is detailed. Following on from this, an operational result is described where a GIS based query operation can be used to determine a more logical scene representation using known geographical constraints. This approach has enable a significantly different spatial context to be defined for the geographic space that terrestrial mobile video captures by optimising it in terms of areal coverage and perceptible depth.