<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">count includes everything in the interpolation radius.<div><br></div><div>Use binmode=True on writers.gdal if you want the points only in the pixel. It is discussed in more detail in the docs at <a href="https://pdal.io/en/latest/stages/writers.gdal.html">https://pdal.io/en/latest/stages/writers.gdal.html</a> </div><div><br></div><div>Howard</div><div><br id="lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>On Dec 14, 2023, at 11:57 AM, lefsky--- via pdal <pdal@lists.osgeo.org> wrote:</div><br class="Apple-interchange-newline"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div><p><font face="monospace">I wrote the following code to calculate point density. While it produces results that have the correct spatial pattern, the absolute values appear to be incorrect. The image is 3938 pixels by 3938 pixels and the mean pixel value is 32.8, so the total number of points from the PDAL calculation is <br>
</font></p><p><font face="monospace">3938*3938 * 32.8 = 483403808.8 </font></p><p><font face="monospace">but there are only 164022975 points in the original laz file, so the estimate of </font><span style="font-family:monospace">483403808.8 is just about 3 times larger than the number of points in the las (2.947 top be exact) </span><br></p><p><span style="font-family:monospace">Or have I misunderstood something?</span></p><p><span style="font-family:monospace">M</span></p><p>Image Statistics:</p><p><img alt="image.png" height="101" style="margin-right: 0px;" src="cid:ii_lq5h0c3i4"></p><p>json:</p><p><font face="monospace">
"pipeline":[<br>
{<br>
"type":"readers.las",<br>
"filename":"/home/lefsky/time_trials/tile_67_136_sub_2.laz"<br>
},<br>
{<br>
"type":"writers.gdal", "filename":"/home/lefsky/time_trials/tile_67_136_sub_2_density.tif", "dimension":"Z",<br>
"data_type":"Float32",<br>
"output_type":"count",<br>
"resolution": 1<br>
}<br>
]<br>
}<br>
<br>
</font></p></div><div><font face="monospace"><br></font></div><font face="monospace"><br clear="all"></font><div><font face="monospace"><br></font></div><font face="monospace"><span class="gmail_signature_prefix">-- </span><br></font><div dir="ltr" class="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div><font face="monospace">Michael Lefsky (He/His) <br></font></div><div><font face="monospace">Home Location: HVHF+GH<br></font></div><div><font face="monospace">Cell: 970-980-9036</font></div><div><div><font face="monospace"><span style="color:rgb(51,51,51);font-size:12px;white-space:nowrap"><a href="http://www.researcherid.com/rid/A-7224-2009" target="_blank">http://www.researcherid.com/rid/A-7224-2009</a></span><br></font><div><font face="monospace"><br></font><div><em style="color:rgb(96,96,96);font-size:11px"><font face="monospace"><strong>“</strong><strong>for being prematurely, and worse, intuitively right — there’s a heavy price. But for being wrong — no, not so long as you’re wrong in a pack.</strong><strong></strong><strong>" Gary Brecher / Portis</strong></font></em></div></div></div></div><div><em style="color:rgb(96,96,96);font-size:11px"><strong><font face="monospace"><br></font></strong></em></div><div><div style="color:rgb(34,34,34)"><font size="1" face="monospace">*I acknowledge that I live and work on stolen land. This is the land of the Cheyenne, Arapaho, Ute, and Ocheithi Sakowin people. To learn more about these nations, please visit;</font></div><div style="color:rgb(34,34,34)"><font size="1" face="monospace"><a href="http://www.utemountainutetribe.com/" style="color:rgb(17,85,204)" target="_blank">http://www.utemountainutetribe.com/</a><br></font></div><div style="color:rgb(34,34,34)"><font size="1" face="monospace"><a href="http://www.cheyennenation.com/" style="color:rgb(17,85,204)" target="_blank">http://www.cheyennenation.com/</a><br></font></div><div style="color:rgb(34,34,34)"><font size="1" face="monospace"><a href="https://cheyenneandarapaho-nsn.gov/" style="color:rgb(17,85,204)" target="_blank">https://cheyenneandarapaho-nsn.gov/</a><br></font></div><div style="color:rgb(34,34,34)"><font size="1" face="monospace"><a href="https://native-land.ca/" style="color:rgb(17,85,204)" target="_blank">https://native-land.ca/</a><br></font></div></div><div><br></div></div></div></div></div></div></div></div></div>
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