<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">
<div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">I have not had enough time to seriously spend finding an OpenSource alternative.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">UNBC GIS Lab (University of British Columbia) <a href="http://www.gis.unbc.ca/"><font color="#001ed9" style="color: #001ed9"><u>http://www.gis.unbc.ca</u></font></a>/ They are doing some fantastic work there.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">uhmm I believe Stacy Porter did some work which is similar in nature to what you are wondering Morten.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" color="#001ed9" style="font: 13.0px Helvetica; color: #001ed9"><a href="http://www.gis.unbc.ca/courses/geog499/projects/2005/proters1/index.html"><u>http://www.gis.unbc.ca/courses/geog499/projects/2005/proters1/index.html</u><u></u></a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">yes, and it appears she used PCI Geomatics orthoengine for extraction. </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Here are a couple links to investigate further:</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" color="#001ed9" style="font: 13.0px Helvetica; color: #001ed9"><a href="http://www.pcigeomatics.com/cgi-bin/pcihlp/OESE"><u>http://www.pcigeomatics.com/cgi-bin/pcihlp/OESE</u><u></u></a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" color="#001ed9" style="font: 13.0px Helvetica; color: #001ed9"><a href="http://www.pcigeomatics.com/cgi-bin/pcihlp/PACE"><u>http://www.pcigeomatics.com/cgi-bin/pcihlp/PACE</u><u></u></a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Now, there is a very old opensource solution that can also do the parallax maths I believe, although I have not been able to test it, and I do not know anyone who has.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">I am sure the theory is solid though.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">You can also check out <a href="http://mpa.itc.it/markus/spectral_unmixing/"><font color="#001ed9" style="color: #001ed9"><u>http://mpa.itc.it/markus/spectral_unmixing/</u></font></a> about spectral angle mapping. </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Thanks to Markus Neteler and company from Trento Italy, </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">not too sure how that project developed but seeing as he replied here ...</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Anyways there is a good paper in the above link covering image registry using i.ortho.photo (?) in GRASS.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">And you may also want to check out OpenDX, they may have some tricks over there as well.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" color="#001ed9" style="font: 13.0px Helvetica; color: #001ed9"><a href="http://www.opendx.org/"><u>http://www.opendx.org</u><u></u></a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">There is some really good info on methodology of photogrametry analysis there anyways: ie. <a href="http://activetectonics.asu.edu/LabDocs/Orthomax.html"><font color="#001ed9" style="color: #001ed9"><u>http://activetectonics.asu.edu/LabDocs/Orthomax.html</u></font></a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">As for hardware, there are specialized systems that will Externally display a pseudo-3D of stereo pairs, </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">but I do not believe they actually physically process stereo pairs into useable elevation maps for GIS data. </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Perhaps I am wrong, but I am sure these systems are crippling in cost anyways and a fully licensed software solution would be much cheeper.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">This is pretty much all the informations I have attained a few months ago in investigating the same end.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">So hopefully there is something in here that will guide you to your final destination point. </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">Good luck, and I would really love to hear how things develop at your end.</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 13px/normal Helvetica; min-height: 16px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="4" style="font: 13.0px Helvetica">cheers!</font></div> <div><br class="webkit-block-placeholder"></div>Mars<div><br><div><div>On 30-Jun-07, at 7:20 PM, Glynn Clements wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Markus Neteler wrote:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div> <blockquote type="cite"><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I am involved in a project using aerial photographs, earlier we have</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">been using dias and an 'old fashioned' stereoscope for interpretations.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Now we are to get the pictures as files. What kind of hard- and software</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">do we need to view stereoscopic images on screen? Is this possible</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">within grass / ossim or otherwhere in the free software family? Do we</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">need to get some special hardware, or is is possible to calculate the</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">heightinformation from a couple of georeferenced images and then use eg</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">nviz? Does anyone here have any experience on that kind of work?</div> </blockquote><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">As far as I know, there is some stereo support in openGL</div> </blockquote><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I don't think that helps here. AFAICT, Morten is interested in</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">converting a stereo pair of 2D images to 3D, while OpenGL's stereo</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">support amounts to support for rendering to a stereo pair (you still</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">have to render each view separately).</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--<span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Glynn Clements <<a href="mailto:glynn@gclements.plus.com">glynn@gclements.plus.com</a>></div> </blockquote></div><br></div></body></html>