<div dir="ltr">Hi Even.<div>Thanks for the feedback.<br></div><div><br></div><div>Sorry... I'm using GDAL 1.11.3.</div><div>I'm going to double check to make sure I didn't make any mistake.<br></div><div>I'll let you know.</div><div><br></div><div>Cheers,</div><div>Daniele</div><div><br></div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, May 2, 2016 at 2:49 PM, Even Rouault <span dir="ltr"><<a href="mailto:even.rouault@spatialys.com" target="_blank">even.rouault@spatialys.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">Le lundi 02 mai 2016 14:37:39, Daniele Romagnoli a écrit :<br>
> Hi List,<br>
><br>
> I have a reprojectiion tool which creates GeoTIFFs with NoData = NaN.<br>
> I'm creating couple of GeoTIFFs with partially overlapping areas where<br>
> GeoTIFF1 has NaNs in a region and GeoTIFF2 has proper values in the same<br>
> overlapping region and viceversa (GeoTIFF2 has some NaN area while GeoTIFF1<br>
> has valid pixels for same area).<br>
> I have built a VRT on top of them and then translated into a single<br>
> GeoTIFF. However, the result has NaN in those regions.<br>
> I was hoping that the area containing NaNs would have been ignored instead,<br>
> in favor of proper values from the other file.<br>
> Is there any flag, properties or suggestions to make it working?<br>
><br>
> If I configure the reprojection tool to write NoData = -9999 and then use<br>
> gdalbuildvrt -srcnodata -9999, things are working fine.<br>
> So I'm just wondering if the same can be achieved dealing with NaN instead<br>
> of custom values.<br>
<br>
</span>Daniele,<br>
<br>
You didn't mention which GDAL version you use. It is possible that support for<br>
NaN as a nodata value in gdalbuildvrt & the VRT driver was fixed at some point.<br>
>From a quick test with trunk, it works (works with 1.11 branch as well):<br>
<br>
$ cat in1.asc<br>
ncols 3<br>
nrows 3<br>
xllcorner 440720.000000000000<br>
yllcorner 3750120.000000000000<br>
cellsize 60.000000000000<br>
NODATA_value nan<br>
1.0 1.0 1.0<br>
1.0 nan 1.0<br>
1.0 1.0 1.0<br>
<br>
$ cat in2.asc<br>
ncols 3<br>
nrows 3<br>
xllcorner 440720.000000000000<br>
yllcorner 3750120.000000000000<br>
cellsize 60.000000000000<br>
NODATA_value nan<br>
nan nan nan<br>
nan 2.0 nan<br>
nan nan nan<br>
<br>
$ gdalbuildvrt nan.vrt in1.asc in2.asc<br>
<br>
$ gdal_translate nan.vrt /vsistdout/ -of aaigrid<br>
ncols 3<br>
nrows 3<br>
xllcorner 440720.000000000000<br>
yllcorner 3750120.000000000000<br>
cellsize 60.000000000000<br>
NODATA_value nan<br>
1 1 1<br>
1 2 1<br>
1 1 1<br>
<span class="HOEnZb"><font color="#888888"><br>
<br>
Even<br>
<br>
--<br>
Spatialys - Geospatial professional services<br>
<a href="http://www.spatialys.com" rel="noreferrer" target="_blank">http://www.spatialys.com</a><br>
</font></span></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><span style="font-size:12.8px">==</span><br></div><div dir="ltr"><span style="font-size:12.8000001907349px">GeoServer Professional Services from the experts! Visit</span><br style="font-size:12.8000001907349px"><a href="http://goo.gl/it488V" style="color:rgb(17,85,204);font-size:12.8000001907349px" target="_blank">http://goo.gl/it488V</a><span style="font-size:12.8000001907349px"> for more information.</span><br>
==<br>
<br>Ing. Daniele Romagnoli<br>Senior Software Engineer<br><br>GeoSolutions S.A.S.<br><span style="font-size:12.8px">Via di Montramito 3/A</span><br>55054 Massarosa (LU)<br>Italy<br>phone: +39 0584 962313<br>fax: +39 0584 1660272<br><br><a href="http://www.geo-solutions.it" target="_blank">http://www.geo-solutions.it</a><br><a href="http://twitter.com/geosolutions_it" target="_blank">http://twitter.com/geosolutions_it</a><br><br>-------------------------------------------------------<br><p><span lang="IT"><font size="1"><b>AVVERTENZE AI SENSI DEL D.Lgs. 196/2003</b></font></span></p><p><span lang="IT"><font size="1">Le
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