[gdal-dev] gdal.AutoCreateWarpedVRT returning different results than osr.CoordinateTransformation

[Billy Newman]

I ran a quick test and confirmed that gdal.AutoCreateWarpedVRT is returning
different results than osr.CoordinateTransformation.

I.E. I opened a file using:
Dataset dataset = gdal.Open("/images/image.tif");

I grabbed the corner point and used
osr.CoordinateTransformation.TransformPoint(), to transform the point into
EPSG:4326.

I warped the dataset using gdal.AutoCreateWarpedVRT, grabbed the corner
point and the corner point was a little different.

I am not sure if that is expected behavior or not.  Hopefully I am just
missing some static files and one of the transformations was not quite
right.  I tried all the different sampling algos available for the
AutoCreateWarpedVRT and that did not make a huge difference.

Is warp using a different method to transform the points?  If so is that
transformation available via the API?

I understand that not all calcs may be exact between these two but I would
expect the corner point to be almost exact.

Any ideas?

Thanks,
Billy
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