licensing of terrain data?

CesiumJS
1

Hi,

There is increasing interest in improving geo browsing capabilities
here at work [0]. We've been doing some prototyping work in Cesium as
from what I've seen so far it appears to be an excellent base for a
variety of applications. Over the coming few weeks we'll be required
to do demos from time to time. In order to be less dependent on
external resources, is it possible for me to serve my own copy of the
terrain data that is currently being hosted at [1]?

Thanks,
Chris

[0] http://www.nicta.com.au
[1] http://cesium.agi.com/terrain

2

Hi Chris,

Glad to hear you like what you see in Cesium so far!

The terrain data hosted on cesium.agi.com is a processed version of the SRTM data from CGIAR [0]. I processed the data using GDAL’s gdal2tiles.py script [1], which I modified to generate TIF files instead of PNGs. I then converted those to PNGs with the Cesium height encoding technique using custom code adapted from the “proxy” project in the Cesium tree [2]. You can follow these same steps to produce the data yourself if you’d like.

As you may know, I work for a company called AGI [3], as do most of the other current Cesium contributors. AGI is currently hosting a public terrain server with this data for free, and will continue to do so for for the foreseeable future (if I get my way - I can’t promise it, of course). However, we will also sell a terrain server pre-loaded with the data for use on private networks, as a means to offset the cost of acquiring, processing, and hosting the data publicly. So that might be an option for you guys down the road.

In the meantime, though, I have no problem with you caching a bunch of our terrain tiles locally for demos. The entire dataset is 7.5 million tiles, so please don’t download the whole thing. But feel free to download a few tens of thousands of tiles comprising the globe at low detail and an area of interest or two at high detail.

I hope that helps,

Kevin

[0] http://srtm.csi.cgiar.org/

[1] http://www.gdal.org/gdal2tiles.html

[2] https://github.com/AnalyticalGraphicsInc/cesium/blob/imagery_layers/Tools/proxy/src/com/agi/TerrainTranscodingHandler.java

[3] http://www.agi.com/

3

Thanks Kevin, I've done some caching of an area for now.