Discovery Software, STEMgis, Temporal GIS

STEMgis consists of three components:

STEMgis Manager - data loader, management and archive system
STEMgis Viewer - retrieval and multidimensional visualization and analysis tool
STEMgis Publicist - data dissemination including a freely distributable version of the Viewer (STEMgis FreeView)

All spatial and attribute data are stored within STEMgis databases. Every spatial feature and attribute value is stored with a time stamp and a unique identifier. The spatial definition of a feature may change with time, for example, the position of a car or the meandering of a river.


  • ESRI Shape files and DBF attribute files
  • MapInfo MIF files
  • DXF files
  • CSV files
  • GeoTIFF images
  • Other bitmap formats, BMP, PNG, TIF, JPG
  • manual digitizing of vectors

Temporal Queries

  • up to 10 attributes per query
  • specify spatial and temporal limits
  • linear time aggregations using multiples of seconds, minutes, hours, days etc.
  • cyclical time aggregations, e.g., months of the year or days of the week
  • specify depth aggregations
  • on the fly recalculation of temporal and depth statistics

Multitemporal Analysis Tools

  • interpolation
  • point to polygon aggregation
  • point to point aggregation
  • raster arithmetic
  • raster statistics
  • clipping
  • vector to raster conversion
  • volume and area calculation
  • drainage network analysis
  • flood plain analysis
  • distance and border calculation
  • concatenation, extract, combination of raster tiles
  • kernel based statistics
  • slope and aspect calculation
  • determine delta time differences between grids
  • tracking analysis - movement of features within restricted areas or from curfew zones


  • control over feature names, icons, colours, palettes, projections, attributes, features types
  • NGDF metadata related to features and/or attributes, export to XML
  • full database referential integrity
  • comprehensive data checking prior to loading
  • compaction
  • levels of security attached to feature types, affording different levels of access to data types


  • AVI animations
  • Bitmap formats
  • CSV files
  • SIPS images
  • Arc generate format
  • ESRI Shape files and DBF attribute files

Mapping Features

  • 2000 European Petroleum Survey Group (Version 6.3) map projections
  • 100+ user-defined projections
  • unprojected view
  • zoom, pan, zoom to layer, zoom to time etc
  • layer manipulation, on/off, ordering, properties
  • location window
  • datum transformations
  • datum offset calculation
  • reprojection of raster data


  • play, playback, step through
  • play once
  • multilayer animations
  • select any time slice or depth range using time and depth bars
  • perspective view animation of 2.5D surfaces
  • animation of temporal transects


  • publish datasets and distribute with a free version of the STEMgis Viewer
  • customizable splash screen and installation
  • include coastline maps, powerpoint presentations, Adobe PDF documents, workspace files
  • specify selected projection
  • allows STEMgis FreeView to be started from external programs displaying a particular set of layers and views
  • customizable license file
  • customizable web links



System requirements

  • Pentium II processor (minimum)
  • 64Mb RAM (minimum)
  • 250Mb free disk space
  • Windows 98, ME, NT4, 2000, XP, Server 2003


  • Creates data model in Microsoft Access, or,
  • Creates data model in Microsoft SQL Server


  • quick preformatted print
  • layout designer with access to temporal views


  • proportional symbols
  • palette shading, points, lines, polygons, grids
  • pie charts
  • speedometer graphs
  • bar charts
  • proportional line widths
  • 3D perspective views, including real-time view angle, vertical exaggeration and lighting conditions
  • pairwise attribute display, e.g., size for one attribute and colour/symbol type for the second
  • temporal graphs
  • depth graphs
  • attribute versus attribute graphs
  • transects
  • transects along a route, e.g., along a river
  • transects of depth profile data
  • plot path of rain drop on a terrain and view transect of height profile
  • display vector field data as arrow
  • display raster data as arrows
  • display raster data as full RGB or HSV combinations
  • Lambertian shading of raster data
  • display image, movies and documents relating to spatial features

Workspaces and Views

  • can open any STEMgis database from a Viewer session
  • save and open STEMgis workspace files which will perform all the queries and graphical setup from a previous session
  • double-clicking workspace files opens Viewer with saved datasets
  • save hierarchical list of views and animations