Digital orthoimages are composed of an array of georeferenced pixels, or picture elements, that encode ground reflectance as a discrete digital value. Framework - collection of basic geospatial data upon which users may collect, register or integrate geospatial information. It is the essential ingredient in developing a common coordinate reference for all other geographic features. Features that are connected to one another hydrologically form a skeletal structure representing the branching patterns of surface-water drainage systems. These linear surface water features comprise the streams coverage.
Shores are polygonal features for any body of standing water, such as lakes or ponds.
Any standing body of water that is connected to a linear feature will be represented in the streams coverage as a line. A digital orthophoto may be made up of several images mosaicked together to form the final image. Photo Control Points - points for which ground coordinates have been determined by a ground control survey. Triangulation Points - points for which ground coordinates must be determined by analytic triangulation. Texas Geographic Information Systems Standards Committee.