Data Identification: a user needs assessment is carried out in order to identify user information This helps identify the data required for their applications. Subsequently, the appropriate data sources and their location are identified.
Analogue data collection: in many cases, a lot of the available data are in the form of analogue These maps are collected and evaluated as to their quality, completeness and complexity. If acceptable, they may then be prepared for digitization. In large projects, where maps will be digitized over a long time, maps should be stored in optimum temperature and humidity conditions while awaiting digitization.
Analogue Data Preparation: at this stage, the features to be digitized are chosen and feature codes assigned to them. If necessary, they are highlighted for easy recognition. The manuscript may also require reformatting to conform to the digitization method to be used, e.g reduction in size, opaquing, cleaning etc.
Digitization and Editing: digitization is the conversion of analogue data to digital by a variety of techniques. During editing, the digital data are displayed, checked and corrected for errors. If no attribute data were entered during digitization, they are entered at this stage.
Methods of Digitization
- Vector format: manual digitizing; onscreen digitization
- Raster format: manual gridding; scanning; video digitizing