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<DIV><FONT face="Courier New" size=2>Not sure if this has been covered yet but I
read a thread recently that discussed image resampling with GDAL. The results
with one resampling pass were not quite satisfactory ... </FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>At any rate, here is technique you can use
to create smooth, anti-aliased resampled images with GDAL. It's not perfect and
it is a bit more work but it does generate good results.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>===============================================================</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sample Batch File</FONT></DIV>
<DIV><FONT face="Courier New"
size=2>===============================================================</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV>
<DIV><FONT face="Courier New" size=2>gdalwarp -of GTiff -ts 900 900
<STRONG>input_filename.tif</STRONG> -rcs resampled_01.tif<BR>gdalwarp -of GTiff
-ts 800 800 resampled_01.tif -rcs resampled_02.tif<BR>gdalwarp -of GTiff -ts 700
700 resampled_02.tif -rcs resampled_03.tif<BR>gdalwarp -of GTiff -ts 600 600
resampled_03.tif -rcs resampled_04.tif<BR>gdalwarp -of GTiff -ts 500 500
resampled_04.tif -rcs resampled_05.tif<BR>gdalwarp -of GTiff -ts 400 400
resampled_05.tif -rcs resampled_06.tif<BR>gdalwarp -of GTiff -ts 300 300
resampled_06.tif -rcs resampled_07.tif<BR>gdalwarp -of GTiff -ts 200 200
resampled_07.tif -rcs resampled_08.tif<BR>gdalwarp -of GTiff -ts 128 128
resampled_08.tif -rcs resampled_09.tif</FONT></DIV>
<DIV><FONT face="Courier New"></FONT> </DIV><FONT size=2>
<DIV><BR><FONT face="Courier New">gdal_translate -of BMP resampled_09.tif
resampled_10.bmp</FONT></DIV>
<DIV><FONT face="Courier New"></FONT> </DIV>
<DIV><FONT face="Courier New">del resampled_01.tif<BR>del
resampled_02.tif<BR>del resampled_03.tif<BR>del resampled_04.tif<BR>del
resampled_05.tif<BR>del resampled_06.tif<BR>del resampled_07.tif<BR>del
resampled_08.tif<BR>del resampled_09.tif</FONT></DIV>
<DIV><FONT face="Courier New"></FONT> </DIV>
<DIV><FONT
face="Courier New">===============================================================</FONT></DIV>
<DIV><FONT face="Courier New"></FONT> </DIV>
<DIV><FONT face="Courier New">This will generate a nicely smoothed image by
using successive passes. Please forgive the redundancy if this has been
suggested already.</FONT></DIV></FONT></DIV></BODY></HTML>