<div dir="ltr"><div><div>Hey,<br></div><div>I'm not M.Ramsey, I'm just a pointcloud user.</div><br>1. : you can "colorize" based on any attributes of points. Traditional point cloud softwares expect usually R G B attributes, but for some you can choose which attributes to use for coloring (CloudCompare).<br>
<br></div>2 : We have thought about visualisation (in this area it's about Level Of Details). The best we tried (because of lack of time) is to make another PC_Explode so it returns only a certain number of points per patch.<br>
<div><br></div><div>The next step is to writte points in patch following a quad tree structure (not deep first but breadth-first) (maybe using <a href="http://www.postgresql.org/docs/9.3/static/spgist-examples.html">http://www.postgresql.org/docs/9.3/static/spgist-examples.html</a> , not sure about this).</div>
<div>This way when taking only the first XX points in patches, you ensure these points are always well distributed in the patch.</div><div><br></div><div>This is the best we thought of without duplicating data (not an option with so big data anyway).</div>
<div><br></div><div>3 : about générating a raster from pointcloud :</div><div>You can do it in QGis , Grass Gis, or using GDAL or LasTool. (also in CloudCompare) Usually you have access to sophisticated interpolation methods (square inverse distance, etc etc). It is a hard problem in practice because of memory limitation and possible multiple holes in data.<br>
<br><br>Please feel free to ask if you want more details.<br><br>Cheers,</div><div><br></div><div>Rémi-C</div><div><br></div><div><br></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">2013/10/18 Basques, Bob (CI-StPaul) <span dir="ltr"><<a href="mailto:bob.basques@ci.stpaul.mn.us" target="_blank">bob.basques@ci.stpaul.mn.us</a>></span><br>
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<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Hi all,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Juat watched Paul Ramseys video on point cloud storage and it made me think of a few questions to ask.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Quesitions:<u></u><u></u></span></p>
<p><u></u><span style="font-size:8.0pt;font-family:Symbol"><span>·<span style="font:7.0pt "Times New Roman"">
</span></span></span><u></u><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Sort of a DB processing question, probably not thought about yet, but can the pointcloud be colorized based on a raster/vector of view passed in? As in aerial photos obviously,
but less obvious would be for oblique photos. <u></u><u></u></span></p>
<p><u></u><span style="font-size:8.0pt;font-family:Symbol"><span>·<span style="font:7.0pt "Times New Roman"">
</span></span></span><u></u><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Generalizing of the pointclouds, from my perspective to be used for zoom in/out processes for visualization. Could a average height based on a (pyramid) tiling possibly
be used to get close to a generalizing scheme, I know this approach might offend purists as far as data integrity . .<u></u><u></u></span></p>
<p><u></u><span style="font-size:8.0pt;font-family:Symbol"><span>·<span style="font:7.0pt "Times New Roman"">
</span></span></span><u></u><span style="font-size:8.0pt;font-family:"Comic Sans MS"">There was a question in the video that I watched related to building a surface grid from the pointcloud, I wonder about a simple tile averaging as a method for generating
a grid. Anyone tried and have available some benchmarks for this idea?<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Thanks<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS"">Bobb<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Comic Sans MS""><u></u> <u></u></span></p>
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