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Ha! Ok, my gut was right. Rasters it is.<br>
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And by massive, I just mean 80k images worth of photogrammetric point clouds over 300km2. I know I estimated how many points that is at one point, but I don't recall now.
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<span style="font-family:Helvetica,sans-serif"><strong>Stephen V. Mather</strong></span><br style="font-family:Helvetica,sans-serif">
<span style="font-family:Helvetica,sans-serif"></span></span><span style="font-size:11pt; color:rgb(0,108,86); font-family:Helvetica,sans-serif"><span style="font-family:Helvetica,sans-serif">GIS Manager</span><br style="font-family:Helvetica,sans-serif">
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Howard Butler <howard@hobu.co><br>
<b>Sent:</b> Monday, June 29, 2020 12:50 PM<br>
<b>To:</b> Stephen V. Mather <svm@clevelandmetroparks.com><br>
<b>Cc:</b> pdal <pdal@lists.osgeo.org><br>
<b>Subject:</b> Re: [pdal] Digitized building footprints</font>
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<p><strong><span style="font-size:9px; font-family:Arial"><span style="font-size:9px">WARNING: This email originated outside of Cleveland Metroparks. DO NOT CLICK links or attachments unless you recognize the sender and know the content is safe.</span></span></strong></p>
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<div class="">On Jun 29, 2020, at 10:18 AM, Stephen V. Mather <<a href="mailto:svm@clevelandmetroparks.com" class="">svm@clevelandmetroparks.com</a>> wrote:</div>
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Hi All,</div>
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I am processing a dataset for which I have a digitized building footprints. It'd be even cooler if I had vegetation, but beggers != choosers.</div>
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In principle, I could use filters.overlay, but this is a massive dataset, so I am curious if it makes more sense to rasterize, tile things up, and use filters.colorization.</div>
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<div>Define massive ;)</div>
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<div>I think your instinct to rasterize the footprints is the right one here. filters.overlay is going to do point-in-polygon for every point/poly combo. Most are quickly thrown out, but you're going to be checking every one. A raster mask is going to be much
quicker, and you can control the resolution with gdal_rasterize.</div>
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<span class="" style="font-size:12pt">Happy to test and report back on what is fastest, but in case someone has a hunch, or an alternative recommended approach, I thought I would ask.</span></div>
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<div>I'm curious in how different things might be, but I suspect the approaches will separate quite quickly for significantly sized polygon and point cloud sets.</div>
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<div>Howard</div>
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