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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">OK thanks for the comments. I’ll update the pdal (yes, older version) and look at using the witers.gdal to see how I get on. Many thanks
for your input. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Jon.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Howard Butler <howard@hobu.co>
<br>
<b>Sent:</b> 20 August 2018 14:18<br>
<b>To:</b> Murray, Jon <j.murray3@lancaster.ac.uk><br>
<b>Cc:</b> Andrew Bell <andrew.bell.ia@gmail.com>; pdal@lists.osgeo.org<br>
<b>Subject:</b> Re: [pdal] DSM and DTM mismatch.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I see "writers.p2g". Which version of PDAL are you using? We have refactored writers.p2g to something now called writers.gdal [1], which has many more features and probably some bug fixes. writers.gdal supports setting of an explicit bounds.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">[1] <a href="https://pdal.io/stages/writers.gdal.html">https://pdal.io/stages/writers.gdal.html</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Aug 20, 2018, at 8:09 AM, Murray, Jon <<a href="mailto:j.murray3@lancaster.ac.uk">j.murray3@lancaster.ac.uk</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Ah – apologies. My first post as I explained. As below:</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">DSM:</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">{</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "pipeline":[</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "input1.las",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "type":"filters.reprojection",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "in_srs":"EPSG:27700",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "out_srs":"EPSG:27700"</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "type":"filters.range",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "limits":"returnnumber[1:1]"</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "type":"writers.p2g",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "filename":"dsm1",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "output_format":"tif",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "grid_dist_x":0.5,</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "grid_dist_y":0.5,</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">}</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">DTM</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "pipeline":[</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "input1.las",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "type":"filters.reprojection",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "in_srs":"EPSG:27700",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "out_srs":"EPSG:27700"</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "type":"writers.p2g",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "filename":"dtm1",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "output_type":"idw",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "output_format":"tif",</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> "grid_dist_y":0.5</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"> ]</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">}</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">And the CHM:</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">gdal_calc.py -A dtm1.idw.tif -B dsm1.idw.tif --calc="B-A" --outfile chm1.tif –overwrite</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Regards,</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Jon.</span><o:p></o:p></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span class="apple-converted-space"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></span><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Andrew
Bell <<a href="mailto:andrew.bell.ia@gmail.com">andrew.bell.ia@gmail.com</a>><span class="apple-converted-space"> </span><br>
<b>Sent:</b><span class="apple-converted-space"> </span>20 August 2018 13:58<br>
<b>To:</b><span class="apple-converted-space"> </span>Murray, Jon <<a href="mailto:j.murray3@lancaster.ac.uk">j.murray3@lancaster.ac.uk</a>><br>
<b>Cc:</b><span class="apple-converted-space"> </span><a href="mailto:pdal@lists.osgeo.org">pdal@lists.osgeo.org</a><br>
<b>Subject:</b><span class="apple-converted-space"> </span>Re: [pdal] DSM and DTM mismatch.</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">You should post pipelines to show how exactly you're creating the files.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">On Mon, Aug 20, 2018 at 8:49 AM, Murray, Jon <<a href="mailto:j.murray3@lancaster.ac.uk" target="_blank"><span style="color:purple">j.murray3@lancaster.ac.uk</span></a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Hello PDAL users,<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">This is my first post to you all, having just joined the mailing list, so I hope this post is appropriate. I have a problem that I hope there is a PDAL (or possibly GDAL) based solution for. I have created both DSM and DTM from LiDAR (.las)
data, using the appropriate PDAL filters/writers etc. It all works well, however there is a slight mismatch in output file sizes.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">The DSM comes out at (3069,1094) and the DTM at (3069,1092), from the same input.las file. This prevents the CHM from being created (GDAL side now) as of course, the dimensions must match. I have tried reprocessing the DSM/DTM and changing
grid sizes x/y, but no success.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Can anyone recommend a solution to this problem please? In short what can I do to make the DTM/DSM sizes match?<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Many thanks,<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Jon.<o:p></o:p></p>
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<p class="MsoNormal"><br>
_______________________________________________<br>
pdal mailing list<br>
<a href="mailto:pdal@lists.osgeo.org"><span style="color:purple">pdal@lists.osgeo.org</span></a><br>
<a href="https://lists.osgeo.org/mailman/listinfo/pdal" target="_blank"><span style="color:purple">https://lists.osgeo.org/mailman/listinfo/pdal</span></a><o:p></o:p></p>
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<p class="MsoNormal">--<span class="apple-converted-space"> </span><o:p></o:p></p>
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<p class="MsoNormal">Andrew Bell<br>
<a href="mailto:andrew.bell.ia@gmail.com" target="_blank"><span style="color:purple">andrew.bell.ia@gmail.com</span></a><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Helvetica",sans-serif">_______________________________________________<br>
pdal mailing list<br>
<a href="mailto:pdal@lists.osgeo.org">pdal@lists.osgeo.org</a><br>
<a href="https://lists.osgeo.org/mailman/listinfo/pdal">https://lists.osgeo.org/mailman/listinfo/pdal</a></span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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