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<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif">Greetings,<br>
<br>
Our team decided to use GDAL in our code to support certain business requirements. Each time we do an analysis we need the elevation profile lines, our analyses run through 10,000s of such cases across a large area. Which means we need to extract these elevation
profile lines 10,000s per session. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif">Currently, we have a partially-working solution in C# (we’re using C# bindings for GDAL) but when we load several DTED files and increase their resolution we run into “OutOfMemoryExceptions”.
We are “manually” extract all of the elevations out of these files into large lists in memory (10’s of millions of elevations, spread over large area). How would you go about making sure that you could do this quickly and efficiently? We need technical guidance
on how to support the objectives we outlined below within the GDAL/OGR framework.<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Segoe UI",sans-serif">Objectives:<br>
1) We have a large set of terrain files in DTED format, we want to load these into the application<br>
2) We want to potentially warp the terrain data (increase resolution or crop the extents of the terrain data) which they have loaded into the application<br>
3) Once the terrain data is loaded into the application, we want to:<br>
• extract elevation profile lines from the terrain data (i.e., the list of elevations, in meters, between two input lat/lon coordinates).<br>
• extract elevation, in meters, at a single input lat/lon coordinate.<br>
<br>
Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Nabil Adechoubou<o:p></o:p></p>
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