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<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Hello,</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">We wrote a GDAL</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">driver</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">for our own format but I have recently noticed that gdalinfo is reporting incorrect corners</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> for our driver, but not for the equivalent datafile in ENVI format. </FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">It looks like the ENVI driver is correctly determining the sign on the pixel size (which appear to always</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">be positive), whereas our driv</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">er is not and giving y-coordinates</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">in the</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> opposite direction from the origin then what they are.</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> To be more spe</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">cific we currently use UTM projection and it</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">s giving the coordinate of the lower right hand corner as higher than top left coordinate</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> when it should be lower (for northern hemisphere). I thought it was because our header file was reporting a positive y-scale when it should be negative (and in fact it does work as expected if I manually edit the header file and give it a negative y-scale), but the ENVI .hdr file also ha</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">s a positive y-scale, so the driver must be checking and assigning the proper sign.</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Rather than dig through the code for a while I was hoping someone might be able to point me in the right direction for where this check might be</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">occurring</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">, and where it should be done</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">? </FONT></SPAN><SPAN LANG="en-us"> </SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Thanks in advance!</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">matt</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
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