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<DIV><FONT face=Arial size=2>Greetings,<BR><BR>My apologies in advance if the
following is stupid but I am not a GIS expert (probably not even a GIS
novice).<BR><BR>Some time ago I had call to transform corner coordinates from
"Australian Geodetic Datum 1966" to WGS84 so that I could accurately drape some
nautical charts in GeoTiff format onto Google Earth. I used a utility called
GEOTRANS2 which produced excellent mathematical results but is decidely clunky
to integrate.<BR><BR>I recently discovered the GDAL utilities and have been
trying to replicate this transformation without success.<BR></FONT></DIV>
<DIV><FONT face=Arial size=2>----------------------------</FONT><FONT face=Arial
size=2></DIV>
<DIV><BR>I have netted down my efforts as follows:<BR><BR>(1) Environment is
Windows XP SP3 and I have installed FWTools 2.2.9.<BR><BR>(2) I have a file
[C:\fwtest\agd66.wkt]
containing:<BR><BR>GEOGCS["AGD66",<BR>DATUM["Australian_Geodetic_Datum_1966",<BR>SPHEROID["Australian
National
Spheroid",6378160,298.249999999996,<BR>AUTHORITY["EPSG","7003"]],<BR>AUTHORITY["EPSG","6202"]],<BR>PRIMEM["Greenwich",0],<BR>UNIT["degree",0.0174532925199433],<BR>AUTHORITY["EPSG","4202"]]<BR> <BR>(3)
I have a file [C:\fwtest\wgs84.wkt] containing:<BR><BR>GEOGCS["WGS
84",<BR>DATUM["WGS_1984",<BR>SPHEROID["WGS
84",6378137,298.2572235630016,<BR>AUTHORITY["EPSG","7030"]],<BR>AUTHORITY["EPSG","6326"]],<BR>PRIMEM["Greenwich",0],<BR>UNIT["degree",0.0174532925199433],<BR>AUTHORITY["EPSG","4326"]]<BR><BR>(4)
I have a file [C:\fwtest\agd66 point.txt] containing a point in
AGD66<BR><BR>-151.1025110 -33.7738883<BR><BR>(5) I have a file [C:\Program
Files\FWTools2.2.9\fwtest.bat] containing a single line:<BR><BR>gdaltransform
-s_srs "c:\fwtest\agd66.wkt" -t_srs "c:\fwtest\wgs84.wkt" < "c:\fwtest\agd66
point.txt" > "c:\fwtest\wgs84 point.txt"<BR><BR>(6) I launch the FWTools
shell via the [FWTools Shell] shortcut on the desktop and within the
FWTools shell I key:<BR><BR>fwtest<BR><BR>(7) I inspect the resulting file
[C:\fwtest\wgs84 point.txt] which shows:<BR><BR>-151.102511 -33.7738883
0</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>i.e. no transformation has occurred, with GEOTRANS2
I would have expected a result like:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>-151.103659 -33.7723069 0</FONT></DIV>
<DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>----------------------------</FONT><FONT face=Arial
size=2></DIV>
<DIV><BR>I have tried numerous permutations, including using [-s_srs EPSG:4202
-t_srs EPSG:4326] instead of the *.wkt files (same result) and inserting garbage
into the *.wkt files to see if gdaltransform is actually reading them (which it
seems to be doing).</DIV>
<DIV> </DIV>
<DIV>I have spent some considerable number of hours on this to no avail so time
to run up the white flag - any and all comments
appreciated.</DIV></FONT></FONT></DIV>
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