Lidar, Multi-beam sonar and 3D Laser scanners are used to map and monitor heights, depths, areas and objects. These measurements result in so called point clouds. A point cloud consists of large amounts, often millions, of 3D points with per point one or more attributes.
More and more information products are based on point clouds. Examples are depth and height contours and three dimensional CAD and GIS reconstructions of objects. In many cases it is possible to combine multiple point clouds. In the Netherlands the AHN2/3 is an example of a country wide point cloud based on multiple underlying point clouds.
Point clouds in GeolinQ
Point clouds are easy to import and manage in GeolinQ. GeolinQ supports LAS as well as ASCII as import file format. Multiple attributes per point are supported. These attributes are to be configured by the user and must be linked to the attributes of the point in the input file. GeolinQ supports all EPSG coordinate transformation so virtually every point cloud in any coordinate systems can be imported.
Point cloud retrieval
The ISO19115 metadata standard is available as metadata schema for point clouds. It can be used ‘as is’ or it can be extended with user-defined attributes to comply with organisational metadata schemas. Point clouds can be queried on their metadata attributes. GeolinQ provides color scales for visualisation of heights and depths and offers functionality to publish individual point clouds or collections of point clouds as WMS layers..
Point cloud datasets are generally large and may contain millions or even a billion of points. Efficient storage, indexing, tiling and dynamic data pyramiding are used to allow fast retrieval and visualisation at all scale levels.