Glossary for Geospatial Science

control point:  Points, elevations, and/or cells which are used to establish map coordinate control for ungeoreferenced objects or objects that are to be used in a process such as Stereo Modeling.  In the manual mosaic process, a control point is a feature in a piece of the mosaic (such as a road intersection) for which the map coordinates are known.  In the raster-to-vector calibration process, a control point is a feature that is co-located between the ungeoreferenced raster object, and the georeferenced vector object overlay.  A control point may be something like a bend in a river or a road intersection that shows on both a raster object and an overlying vector object.  Tying control points together lets TNTmips adjust scale, orientation and geometric distortion between rasters and vectors.

TNTmips’ georeferencing and registration processes rely on control points introduced and identified on the display with the mouse.  (See also: tie points)