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<DIV><FONT face=Arial size=2>Hello guys !</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I currently have some problems in the quality of
the images produced by GDAL/Mapserver.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>We are using MapServer to serve raster imagery to
NASA Worldwind.</FONT></DIV>
<DIV><FONT face=Arial size=2>Our files are in UTM and Worldwind needs WGS84
images so we do reprojection on the fly.</FONT></DIV>
<DIV><FONT face=Arial size=2>Using this, we can clearly see image quality
artefacts between Worldwind (using WGS84, no choice) and a custom internal tool
(showing original data).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I can reproduce the problem using gdalwarp tool
using a very simple command line :</FONT></DIV>
<DIV><FONT face=Arial size=2>gdalwarp -multi -t_srs EPSG:4326 -srcnodata 0
-dstnodata 0 -r near %FileSrc%/*_p_*8bit.tif %FileDest%</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>You can see the result on <A
href="http://benoit.andrieu.free.fr/mapserver/Clipboard02.png">http://benoit.andrieu.free.fr/mapserver/Clipboard02.png</A> :
on the right, the original image and on the left, the resulting
output.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I suspect that using some others settings,
I could improve the quality on gdalwarp's output in a first time and on
mapserver's output in a second time but I don't know where to
start...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So if anyone could help or suggest anything, he
will be welcome !!!</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks in advance,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial
size=2>Benoît</FONT></DIV></DIV></FONT></DIV></BODY></HTML>