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--></style></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Andrew,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You can use filters.sample and just set a small radius.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Mike<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:10.5pt;color:black'>-- <o:p></o:p></span></p><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'>Michael Smith<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'>Remote Sensing/GIS Center<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'>US Army Corps of Engineers</span><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:12.0pt;color:black'>From: </span></b><span style='font-size:12.0pt;color:black'>pdal <pdal-bounces@lists.osgeo.org> on behalf of Andrew Cunliffe <andrewmcunliffe@gmail.com><br><b>Date: </b>Monday, May 13, 2019 at 8:21 AM<br><b>To: </b>PDAL Mailing List <pdal@lists.osgeo.org><br><b>Subject: </b>[pdal] filtering duplicate points<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>Dear all,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I am hoping someone might be able to help me to use PDAL to filter for duplicate points in a point cloud. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>By duplicate, I mean points that are less than a threshold distance (e.g. 0.001 m) from other points in the cloud. I'm working with photogrammetrically-generated point clouds, in some cases ca. 20-30% of the points are 'duplicates' so removing these has some big benefits later in the pipeline.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm looking for a filter that functions like '<a href="https://www.cloudcompare.org/doc/wiki/index.php?title=Remove_duplicate_points">Remove duplicate points</a>' in CloudCompare. I wasn't able to see anything suitable under the filters > cull documentation, unless<span class=gmail-s2> filters.voxelcenternearestneighbor</span> would achieve this with cell set to 0.001?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>If anyone else thinks that a filter.duplicate function might be helpful, I'm happy to submit a feature request via Github.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks<o:p></o:p></p></div><div><p class=MsoNormal>Andy<o:p></o:p></p></div><div><p class=MsoNormal><br>-- <o:p></o:p></p><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><p class=MsoNormal><span style='font-size:7.5pt;color:#999999'>Dr Andrew Cunliffe<br><br>Research Fellow<br>School of Geography<br>University of Exeter</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><p class=MsoNormal>_______________________________________________ pdal mailing list pdal@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/pdal<o:p></o:p></p></div></body></html>