DEMBroker Home Page |
Introduction
Digital Elevation Models represent the heights of land above some datum (think of it as a definition of mean sea level).
There aren't any widely adopted formats for DEM data sets, and they tend to be large.
DEMBroker provides applications with consistent access to digital elevation data from a variety of sources.
Currently, two data sources are linked to DEMBroker
| Database | Region covered | Spatial Resolution(cells per degree of lat.) | Spatial Resolution(cells per degree of log.) | Pixel size(approx.) | Size of entire set |
|---|---|---|---|---|---|
| GTOP30 | World | 120 | 120 | 1km | 2GB |
| Japan Map Center | Japan | 2400 | 1600 | 50m | 2GB |
Demos
| Click to Run | Applet | Description | Pictures |
|---|---|---|---|
| Quick DEM viewer |
 |
This applet uses colours to show the elevation of different points on the globe. You can zoom, pan, or switch between the two data sets. (If you select the Japan 50m dataset while in a different part of the world you will be returned to viewing Japan). | Mt Tsukuba area |
| Quick DEM viewer 2(temporarily out of action) |
|
This applet uses colours to show the elevation of different points on the globe. You can zoom, pan, or switch between the two data sets. (If you select the Japan 50m dataset while in a different part of the world you will be returned to viewing Japan). This version lets you use CountryServer to choose the country of interest |
Applet links above should automatically install the required Java 2 Runtime Edition (JRE) if it isn't already installed on your machine. If the automatic install doesn't work, click here to download the Java 2 Standard Edition (JRE version) from Sun.
DEMBroker client documentation (javadoc)
DEMBean documentation (javadoc)
The applet communicates with DEMBroker using four Java RMI method calls:
demBroker.getConnection() to make a connection
demBroker.listDEMSourceDetails() to list the available data sources for the selection combo
demBroker.getRegion(new DEMSpatialRequest(requestRegion,pixelsPerLatitude,pixelsPerLongitude))
to get the data each time you change the viewing area or the selected DEM source
and
demBroker.disconnect() when it finishes
New datasources can be added to DEMBroker without too much difficulty.
At the moment, DEMBroker can only handle data sets which store data in a regular latitude and longitude grid.
We plan to use DEMBroker to build weather interpolation mechanisms.
Downloads and sample applications
Return to AgModels home page
