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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Several years ago I constructed a GIS library for our application out of various bits of libgeotiff, libtiff, libkml and proj.<o:p></o:p></p><p class=MsoNormal>(this was still the Proj4 era, I think!)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>One thing I tried to get working at the time, but never really did, was to read to geo-data from a GeoTIFF and convert<o:p></o:p></p><p class=MsoNormal>the coordinates to UTM, such that I could then position the image in a UTM space. This worked fine when it did nothing<o:p></o:p></p><p class=MsoNormal>(i.e., when the GeoTIFF was already in UTM) but any other transformation seemed a bit off.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>At the time this wasn’t a big deal, as only a few of our users were making forays into GIS type stuff. Now it is becoming<o:p></o:p></p><p class=MsoNormal>more and more common I wondered if there was a quick and easy way to fix my code in the short term – with a view to <o:p></o:p></p><p class=MsoNormal>more rigorous GIS support when I have more time (ultimately it would be nice to transform between any two ‘arbitrary’ systems)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>To be honest I haven’t looked at this in a long while and feel like I’ve forgotten a lot of what I must have known then<o:p></o:p></p><p class=MsoNormal>in order to get it to the stage it is at currently. Would anyone with more Proj familiarity on the list be willing to glance<o:p></o:p></p><p class=MsoNormal>through my GeoTIFF importation code and comment on what I have done incorrectly, if anything? Or even just outline the<o:p></o:p></p><p class=MsoNormal>steps I should take to get the correct projection info out of a GeoTIFF and convert it?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;mso-fareast-language:EN-NZ'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;mso-fareast-language:EN-NZ'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;mso-fareast-language:EN-NZ'>Dan<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial",sans-serif;mso-fareast-language:EN-NZ'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>