The resolution, or density of wires in the grid, vary from 1,000 to 10,000 lines per inch. An optical device that translates electronic analog representations of images into an array of digital values called pixels. A video digitizer may be used in place of a manual digitizer but, since it produces a raster-based image, software must be provided to convert the data into vector mode for plotters and monitors. The method of manually digitizing data that describes the frequency and relationship among digitized points. Point mode is used to enter a single point.
Line mode is used to enter straight lines by digitizing only the end points.
Stream mode causes a continuous stream of points to be entered as the cursor is moved along a curve. The process of removing boundaries between adjacent polygons having the same values for a specified attribute. DLG Digital Line graph - A common format for transferring vector data from one GIS package to another. Edge detection A software technique for automatic determination of boundaries of plane figures, such as borders between polygons. Ellipsoid A mathematical formulation of the shape of the Earth which is defined by a semimajor axis and its eccentricity.