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<p class="MsoNormal">Dev’s,</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">I have a set of 55,501 bil files in a single directory. They are DEMS data that cover the US in 7.5 minute tiles. I would like to randomly access elevations at a given lat/lon’s from the whole dataset. I created a vrt file from the directory
of bil files, and have been able to access the elevation at a given lat/lon using gdallocationinfo, but because of the size of the dataset, this operation is somewhat slow. Can the vrt be indexed? Or, is there a faster, better way to access the pixels? I
would first like to do this with the utilities before diving into code (C#). The files are regularly named base on their location within a 1 arc-second grid.</p>
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<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal">David</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"><i><span style="font-size:10.0pt; font-family:"Arial","sans-serif"; color:black">David M. Bake<b>r</b></span></i></p>
<p class="MsoNormal"><span style="font-size:10.0pt; font-family:"Arial","sans-serif"; color:black">Senior Advisor – Geoscience Technology</span></p>
<p class="MsoNormal"><span style="font-size:10.0pt; font-family:"Arial","sans-serif"; color:black">Chesapeake Energy Corporation</span></p>
<p class="MsoNormal"><span style="font-size:10.0pt; font-family:"Arial","sans-serif"; color:black"><a href="mailto:david.m.baker@chk.com"><span style="color:blue">david.m.baker@chk.com</span></a></span></p>
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