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</font><p style="margin:0cm 0cm 0pt"><span style="color:black;font-family:"Arial","sans-serif";font-size:10pt">Hey guys,</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span style="color:black;font-family:"Arial","sans-serif";font-size:10pt"> </span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">We have
DigitalGlobe image strips which come with a *.til file.</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">The
geotransform of the til and the separate images have a shift of half a pixel
when opened with GDAL.</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">The reason is
that in the GDAL TIL driver the coordinates are treated as outer pixel edge,
where as it seems like they describe the pixel center, at least in our cases.</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">Does 
anyone know of a description for the TIL format to verify if the GDAL driver or
the TILs from DigitalGlobe are wrong?</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">For now we
fixed it on our side, but you might consider changing the TIL driver to treat the
coordinates as pixel center.</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt"> </span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">Best Regards,</span></p><font color="#000000" face="Times New Roman" size="3">

</font><p style="margin:0cm 0cm 0pt"><span lang="EN-US" style="color:black;font-family:"Arial","sans-serif";font-size:10pt">Dennis</span></p><font color="#000000" face="Times New Roman" size="3">

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