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Be very careful converting vertical units. Especially when there is a different datum or ellipsoid. Often, it's not a simple conversion from ft to meters. I would run a test in corpscon first.<br><br>D
<br>David C Finnegan
<br>Research Physical Scientist
<br>CRREL
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<br>Message sent via my BlackBerry Wireless Device
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<b>From</b>: liblas-devel-bounces@lists.osgeo.org <liblas-devel-bounces@lists.osgeo.org>
<br><b>To</b>: Howard Butler <hobu.inc@gmail.com>
<br><b>Cc</b>: liblas-devel@lists.osgeo.org <liblas-devel@lists.osgeo.org>
<br><b>Sent</b>: Mon Nov 01 22:52:59 2010<br><b>Subject</b>: Re: [Liblas-devel] las2las vertical unit conversion
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<div>Hello Everyone,</div>
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<div>This process " converting vertical units from foot to meter and vise versa" is very important and it is usually needed when comparing multiple LiDAR data from different sources.</div>
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<div>Example: " When studying erosion in certain area, we need to have LiDAR data taken in different time epochs. These data, if you have them, are usually not in the same measuring units". </div>
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<div>In my case, I have the elevation in one set of data in "US Survey feet" and the other set is in "meter". For now, I'm thinking to do las2txt, then convert the elevation value, then back to las file.</div>
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<div>It would be really nice to have this process implemented in las2las.</div>
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<div>Thank you very much,</div>
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<div>Best regards,</div>
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<div>Ibraheem<br><br></div>
<div class="gmail_quote">On Mon, Nov 1, 2010 at 8:14 PM, Howard Butler <span dir="ltr"><<a href="mailto:hobu.inc@gmail.com">hobu.inc@gmail.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class="gmail_quote"><br>On Nov 1, 2010, at 4:10 PM, Brady Callahan wrote:<br><br>> Is there a way to use las2las to convert or scale Z units? I just used las2las to translate data from EPSG:26910 to EPSG:2992 and it worked fantastic! It took less than 25% of the time that LP360 (GeoCue) does for the same operation! However, my Z units (meters) still need to be converted to international feet. Is that possible with las2las?<br>
<br>I don't see any reason why we couldn't, but it is not possible just now.<br><br>What about:<br><br>--point-translate "x*1.0 y*1.0 z*3.2808399"<br>--point-translate "z+20"<br>--point-translate "z-20"<br>
<br>I'd be interested in hearing feedback on this before implementing for 1.6.0b2's las2las. Look good?<br><br>Howard<br><br>_______________________________________________<br>Liblas-devel mailing list<br><a href="mailto:Liblas-devel@lists.osgeo.org">Liblas-devel@lists.osgeo.org</a><br>
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