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<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;">Hi!</div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;"> </div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;">You can use LAStool to generate the vectors ("las2iso" for example).<br />
SPDlib for Qgis is very interesting too.</div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;"><br />
For the geomorphological analysis , I work with the DTM, but I don't know if it's the best method, I'm not topographer...;-)</div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;"> </div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13.33px; font-style: normal; font-weight: 400;"> </div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 13px; font-style: normal; font-weight: 400;"> <em style="background-color: rgba(255, 255, 255, 0);">Cordialement,</em>
<div><em style="background-color: rgba(255, 255, 255, 0);"> </em></div>
<div><span style="font-size: 9pt;"><span style="color: rgb(0, 102, 255);"><strong><em style="background-color: rgba(255, 255, 255, 0);"> Guayente CORRAL BROTO</em></strong></span></span></div>
<div><span style="color: rgb(0, 102, 255); font-family: "Tahoma",sans-serif; font-size: 9pt;"><em> </em></span><span style="font-size: 8pt;"><span style="color: rgb(0, 102, 255); font-family: "Tahoma",sans-serif;"><em>Hydrogéologue / EurGeol n°1336 </em></span></span></div>
<div> </div>
<div><img height="162" src="cid:WC20170313071824.802613@topodoc.com" style="width: 97px; height: 42px;" width="351" /></div>
<div><span style="background-color: rgba(255, 255, 255, 0);"><em> </em></span></div>
<div>
<div><span style="font-size: 8pt;"><em style="background-color: rgba(255, 255, 255, 0);"><span style="color: rgb(0, 102, 255);"> </span><a href="http://www.survey-groupe.fr/" target="_blank"><span style="color: rgb(0, 102, 255);">http://www.survey-groupe.fr</span></a></em></span></div>
</div>
<div><span style="font-size: 8pt;"><span style="color: rgb(0, 102, 255);"><span style="background-color: rgba(255, 255, 255, 0);"> </span></span></span></div>
<div><span style="font-size: 8pt;"><strong><a href="x-apple-data-detectors://1/0" style="background-color: rgba(255, 255, 255, 0);" target="_blank"><span style="color: rgb(0, 102, 255);">Chemin d'Enrobert</span></a></strong></span></div>
<div><span style="font-size: 8pt;"><strong><a href="x-apple-data-detectors://1/0" style="background-color: rgba(255, 255, 255, 0);" target="_blank"><span style="color: rgb(0, 102, 255);">32200 Gimont</span></a></strong></span></div>
<div><span style="font-size: 8pt;"><span style="background-color: rgba(255, 255, 255, 0);"> - <u>Tél</u>: <a href="tel:+33%20%280%295%2062%2065%2067%2065" target="_blank"><span style="color: rgb(0, 102, 255);">+33 (0)</span></a><a href="tel:+33%20%280%295%2062%2065%2067%2065" target="_blank"><span style="color: rgb(0, 102, 255);">5 62 65 67 65</span></a></span></span></div>
<div><span style="font-size: 8pt;"><span style="background-color: rgba(255, 255, 255, 0);"> - <u>Mob:</u> <a href="tel:+33%20%280%296%2048%2074%2043%2067" target="_blank"><span style="color: rgb(0, 102, 255);">+33 (0)6 48 74 43 67</span></a></span></span></div>
<div> </div>
</div>
<div style="color: rgb(0, 0, 0); font-family: Tahoma; font-size: 16px; font-style: normal; font-weight: 400;">
<blockquote style="padding-right: 0px; padding-left: 5px; margin-right: 0px; margin-left: 5px; border-left-color: rgb(0, 0, 0); border-left-width: 2px; border-left-style: solid;">-----Original Message-----<br />
From: dandrigo <lcelati@latitude-geosystems.com><br />
To: qgis-user@lists.osgeo.org<br />
Date: Sat, 11 Mar 2017 02:33:02 -0700 (MST)<br />
Subject: [Qgis-user] Geomorphological microstructures 's footprint extraction?<br />
<div style="font-family: monospace, courier new, courier;">Good morning,<br />
<br />
<br />
We have as input a lidar point cloud (800 000 points) which is the result of<br />
one our classification (this cloud represent only our geomorphological<br />
structures class.) Then,from this cloud we generated a DTM (20cms).<br />
<br />
Our goal is to delimit automatcally the footprint of these microstructures<br />
with a polygonal vector.<br />
<br />
Pouvez vous nous éclairer sur les différentes méthodes et outils permettant<br />
de faire celà?<br />
Could you throw light for us about methods and tools doing this task?<br />
<br />
Is it possible to capture this polygonal layer directly from the points<br />
cloud? (hull).<br />
Or would it be preferarable to work from the DTM raster or one of this<br />
derivatived (vector level curves, slope raster map, exposure raster map,<br />
shading, etc.)? For instance, the slope raster map seems to be an<br />
interesting criterion to identify and isolate the base of these<br />
microstructures. Is would be possible to do an automatic vectorization?<br />
<br />
Below, a screenshot showing the points cloud and another showing slope<br />
raster :<br />
<br />
<<a href="http://osgeo-org.1560.x6.nabble.com/file/n5311838/SS_cloud.jpg" target="_blank">http://osgeo-org.1560.x6.nabble.com/file/n5311838/SS_cloud.jpg</a>><br />
<br />
<<a href="http://osgeo-org.1560.x6.nabble.com/file/n5311838/SS_raster_slope.jpg" target="_blank">http://osgeo-org.1560.x6.nabble.com/file/n5311838/SS_raster_slope.jpg</a>><br />
<br />
Thank you very much for your usefull help.<br />
<br />
<br />
<br />
<br />
--<br />
View this message in context: <a href="http://osgeo-org.1560.x6.nabble.com/Geomorphological-microstructures-s-footprint-extraction-tp5311838.html" target="_blank">http://osgeo-org.1560.x6.nabble.com/Geomorphological-microstructures-s-footprint-extraction-tp5311838.html</a><br />
Sent from the QGIS - User mailing list archive at Nabble.com.<br />
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</blockquote>
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