<html><body><div style="color:#000; background-color:#fff; font-family:verdana, helvetica, sans-serif;font-size:10pt"><div><span>Hello Luis,</span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><span>I'm about to commit a sacrilegious act on the GRASS-user list but it would seem that Martin Isenburg's LAStools software is more appropriate for this stage of your lidar processing.</span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color:
transparent; font-style: normal;"><span>http://rapidlasso.com/lastools/</span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><span>My workflow is to do the tasks you mention below (including the point cloud visualization and DEM generation) in LAStools and then import the DEM / DTM to GRASS for all subsequent processing.<br></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style:
normal;"><span>Best,</span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: verdana,helvetica,sans-serif; background-color: transparent; font-style: normal;"><span>Rebecca</span></div><div><br>
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<div style="font-family:Tahoma; font-size:13px"><font size="2" face="Tahoma">Rebecca Bennett<br>
Postdoctoral Associate, Wired! Group<br>
Department of Art, Art History and Visual Studies<br>
Duke University, Durham, NC<br>
<a href="http://www.pushingthesensors.com/">www.pushingthesensors.com</a></font></div>
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</div><div><br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; margin-top: 5px; padding-left: 5px;"> <div style="font-family: verdana, helvetica, sans-serif; font-size: 10pt;"> <div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"> <div dir="ltr"> <hr size="1"> <font size="2" face="Arial"> <b><span style="font-weight:bold;">From:</span></b> Luis Ramirez <lu.ramirez.c@gmail.com><br> <b><span style="font-weight: bold;">To:</span></b> grass-user@lists.osgeo.org <br> <b><span style="font-weight: bold;">Sent:</span></b> Monday, 26 August 2013, 9:03<br> <b><span style="font-weight: bold;">Subject:</span></b> [GRASS-user] v.lidar.edgedetection, v.surf.bspline and visualization issues<br> </font> </div> <div class="y_msg_container"><br>Hi there,<br><br>I´m being working with Grass Gis just for few weeks. I´m trying to <br>generate a dsm and dtm from LIDAR data. I imported my data as LAS and i
<br>was following the steps explained in the Grass Gis Book of neteler and <br>mitasova. However, I'am having some problems that are transforming an <br>easy task into a time-consuming-nightmare. the first thing that I do not <br>understand is why v.lidar.edgedetection works under Grass Gis 6.4. and 7 <br>instaled in a Virtual machine with Ubuntu but not in Grass Gis 6.4. and <br>7 in a windows 7 Computer. after calculating the first two regions (from <br>9) it crashes. I tried to increment the parameters "see" and "sen" up to <br>the value 10. it is able to calculate a bit more but it still craches. <br>after googleing it i Just get information about a bug detected in 2006. <br>I would really apreciate to be able to run this module in a windows 7 <br>computer. do you maybe have a clue?<br>the second issue is related to v.surf.bspline. I am using a very small <br>map of 1km2 with 118798 points for testing (the goal is to use the <br>procedure for a map
at least 20 times larger than this one). However, <br>Grass Gis 6.4 and 7 (for Ubuntu and For Windows) show me a warning <br>message. it says that it could take too long depending on the amount of <br>points. I already tried with different values for the parameters" sie" <br>and "sin" but it doesnt get any better. I just left the computer <br>calculating for few hours but I´m not really getting any result. do <br>anyone have an Idea what I´m doing wrong?<br>Finally, I´m being trying to get a 3D visualization of the points but <br>both the monitors of the GUI and the wxs ended up crashing before I can <br>see a thing. is that a known problem? there is any known reason for such <br>a problem or even better, a solution or an alternative?<br><br>Thank you in advance!<br><br>Luis<br><br>_______________________________________________<br>grass-user mailing list<br><a ymailto="mailto:grass-user@lists.osgeo.org"
href="mailto:grass-user@lists.osgeo.org">grass-user@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/grass-user" target="_blank">http://lists.osgeo.org/mailman/listinfo/grass-user</a><br><br></div> </div> </div> </blockquote></div> </div></body></html>