These types of savings are important in hard-drive infrastructure. As an analogy, Microsoft Windows-based GIS commonly allows users to store algorithms sufficient to reconstruct the image using a common database. ER Mapper allows users to visualize geographically distributed descriptive data in various ways. For example, data can be viewed as a flat map, a three-dimensional map, or a scattergram. The scattergram allows users to zoom in on selected map regions and to visualize whether pixels are concentrated or dispersed.
Users can also analyze cell values in tabular form.
All these functions flowed comfortably. The only rough spots we encountered were some unrefined transitions of ER Mapper from UNIX to Windows 95. For example, the signature by band was difficult to implement and was incorrectly documented in the manual. ER Mapper allows a variety of options for manual and automatic contrast stretching. Users can specify contrast stretching by altering a curve of digital numbers while viewing screen-output values.