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“DTED is Dead” Map


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Oh, yeah.

The good news is that the European Union finally seems to send directives to member states to open their land survey databases to the general public (for free, or at least for marginal fees covering the costs of filling out a web form, data retrieval, and transmission), including LIDAR scans. Over time we will see high-res data percolating into future Steel Beasts releases, probably as additional map package installers.

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3 hours ago, Gibsonm said:

Ah no updated UK terrain then I suspect (not meant as a political statement).

I think the high res data for the UK is already available regardless of any affiliation with the EU. At the same time, several EU countries had their high res data available for a few years already, like Spain, the NL and others.

Edited by stormrider_sp
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4 hours ago, stormrider_sp said:

I think the high res data for the UK is already available regardless of any affiliation with the EU.

Yes but I suspect it isn't "free"/"marginal fee", as per the new EU directive.

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1 hour ago, Gibsonm said:

Yes but I suspect it isn't "free"/"marginal fee", as per the new EU directive.

Yes, free, at least for european citizens. As I remember, the problem was always both Airbus and DLR, the german space agency trying to make good profits on their data. The UK, NL, Spain, DK and others already provided high res data for free, including Lidar. Btw, same thing for the US.

Edited by stormrider_sp
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Airbus/DLR are a different case, and compared with traditional prices, their were actually pretty low. They used protogrammetry from archived satellite images to create between 10m and down to 4m resolution terrain databases based on the time stamps & position reconstruction of the satellites as correction factors. This is a completely different approach than traditional and aerial land surveys, or LIDAR scans.

 

To give an example, German law actually stipulated that public expenses to generate data were to be recouped by the actual users of said databases, hence the prices of up to 200 EUR per square kilometer (which is sorta-kinda okay if you need five square kilometers of terrain data for a twenty kilometer long stripe to plan pouring concrete for a new road with knowledge about adjacent terrain, 200m left and right.

But it's impossible to work with once that you'd like 20,000 square kilometers for some obscure computer game, even if you get an 80% discount). If you generate waste, you pay waste disposal fees. If you want terrain data, pay for their generation. In a way it's a fair principle. The only problem is that the fees were so high that less than 1% of the actual costs were recouped, at which point insisting on the traditional method is becoming a very German debate about "principles". ;)

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On 1/7/2021 at 9:40 AM, Ssnake said:

Airbus/DLR are a different case, and compared with traditional prices, their were actually pretty low. They used protogrammetry from archived satellite images to create between 10m and down to 4m resolution terrain databases based on the time stamps & position reconstruction of the satellites as correction factors. This is a completely different approach than traditional and aerial land surveys, or LIDAR scans.

Airbus / World DEM is radar data from the Tandem-X satellites.

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Tandem-x in my opinion is one of the most interesting sources. In comparison with SRTM or Alos Palsar which operate in the C and L bands, TerraSAR-X/Tandem-X operates on the X band. It provides data with a lot less noise because of its lower ground penetration. Think that in a desert like environment like the Iraq Kuwaiti border, C band can penetrate up to a few meters in the dry sand while X band will only go a few centimeters. To make matters worse, in that particular environment, prone to floods and which was sometime in the planet's history, the sea bottom, there are several areas of high salinity and thus high water retention: named sabkhas or quicksand, and are not penetrated by radio waves. You end up with a very bumpy terrain when it's just flat.

 

*SRTM also had a X band sensor; the data is provided by DLR, but I find it to be worse in quality than SRTM itself.

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