ABSTRACT
The transfer of data from analog map documents to digital form represents one of the most time consuming and costly steps in creating an operational geographic information system. Much of this encoding activity typically involves a human operator who is interacting with instrumentation (e.g., a digitizer) that transforms two-dimensional, or sometimes three-dimensional, data stored in hardcopy map form into precise digital coordinates. In some cases, which are limited by the quality and complexity of the map documents available, automatic or scan digitizing may be used to create the digital files. The speed of map encoding is substantially increased through the use of scan digitizing, but the cost of scan digitizing instrumentation which is capable of retaining cartographic accuracy is significantly greater than in manual digitizing systems.
