[gdal-dev] gdalwarp - Erroneous Outputs

[Even Rouault]

On lundi 8 avril 2019 08:55:49 CEST Bryant wrote:
> Hello!
> 
> I've been trying to use /gdalbuildvrt/ and /gdalwarp/ to merge, project, and
> crop a set of overlapping images with a new resolution.
> 
> However, I've been running into an issue where the edges of the resulting
> image have nondeterministic, erroneous values (ie. very large and small
> values) and values in regions that I would expect only NoDataValues. The
> images are Float32, 1 banded, and have nodata =
> -340282346638528859811704183484516925440.

That's likely a precision issue in how you specify the nodata value or how it 
is serialized in the VRT. There have been fixes in that area (thinking to
https://github.com/OSGeo/gdal/issues/1071 ), but this is always fragile.

Even

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