<br><font size=2 face="sans-serif">I might try this..is it the good way
to do what I need?</font>
<br>
<br><font size=2 face="sans-serif">1- Use gdal_polygonize.py to create
a boundary (excluding pixels with no value) of each image and save the
boundary as a .shp</font>
<br><font size=2 face="sans-serif">2- Somehow find the intersected region
of the 2 polygons (boundaries) created above and save the result to .shp</font>
<br><font size=2 face="sans-serif">3- Use gdal_rasterize on one of the
original image to burn a nodata value based on the polygon representing
the intersection area</font>
<br>
<br><font size=2 face="sans-serif">I didn't try yet because I don't have
gdal_polygonize.py</font>
<br><font size=2 face="sans-serif">My installation is from MS4W and this
script is not there. I just install GDAL with OSGEO4w and it seems that
this script doesn't exist.</font>
<br>
<br><font size=2 face="sans-serif">If the method above is valid, </font>
<br><font size=2 face="sans-serif">- how can I create a boundary excluding
pixels with nodata?</font>
<br><font size=2 face="sans-serif">- And, of course, where can I get gdal_polygonize.py</font>
<br>
<br><font size=2 face="sans-serif">Thanks!</font>
<br><font size=2 face="sans-serif">Steve</font>
<br><font size=2 face="sans-serif"><br>
</font><font size=3 color=#0066ff><i>Steve Toutant, M. Sc.</i></font><font size=3><br>
Analyste en géomatique<br>
Secteur environnement<br>
Direction des risques biologiques, environnementaux et occupationnels<br>
Institut national de santé publique du Québec<br>
945, avenue Wolfe<br>
Québec, Qc G1V 5B3 </font>
<p><font size=3>Tél.: (418) 650-5115 #5281<br>
Fax.: (418) 654-3144</font><font size=3 color=blue><u><br>
</u></font><a href=mailto:steve.toutant@inspq.qc.ca><font size=3 color=blue><u>steve.toutant@inspq.qc.ca</u></font></a><font size=3 color=blue><u><br>
</u></font><a href=http://www.inspq.qc.ca/><font size=3 color=blue><u>http://www.inspq.qc.ca</u></font></a>
<p><font size=3> </font>
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<td width=40%><font size=1 face="sans-serif"><b>Steve Toutant/INSPQ/SSSS</b>
</font>
<p><font size=1 face="sans-serif">17/07/2009 11:26 AM</font>
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<div align=right><font size=1 face="sans-serif">A</font></div>
<td><font size=1 face="sans-serif">gdal-dev@lists.osgeo.org</font>
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<div align=right><font size=1 face="sans-serif">cc</font></div>
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<div align=right><font size=1 face="sans-serif">Objet</font></div>
<td><font size=1 face="sans-serif">clip intersected </font></table>
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<br><font size=2 face="sans-serif">Hi,</font>
<br><font size=2 face="sans-serif">I have 2 Erdas (.img) images that overlap.
See attached image.</font>
<br><font size=2 face="sans-serif">I need to clip one of the 2 images by
removing the intersected (dark red) part. </font>
<br><font size=2 face="sans-serif">If it's possible, how should I accomplish
this?</font>
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<br><font size=2 face="sans-serif">thanks for your help,</font>
<br><font size=2 face="sans-serif">Steve </font>
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<br>
<br><img src=cid:_1_0722ADB40722AB60005AB972852575F6>
<br>
<br><font size=2 face="sans-serif"><br>
</font><font size=3 color=#0066ff><i>Steve Toutant, M. Sc.</i></font><font size=3><br>
Analyste en géomatique<br>
Secteur environnement<br>
Direction des risques biologiques, environnementaux et occupationnels<br>
Institut national de santé publique du Québec<br>
945, avenue Wolfe<br>
Québec, Qc G1V 5B3 </font>
<p><font size=3>Tél.: (418) 650-5115 #5281<br>
Fax.: (418) 654-3144</font><font size=3 color=blue><u><br>
</u></font><a href=mailto:steve.toutant@inspq.qc.ca><font size=3 color=blue><u>steve.toutant@inspq.qc.ca</u></font></a><font size=3 color=blue><u><br>
</u></font><a href=http://www.inspq.qc.ca/><font size=3 color=blue><u>http://www.inspq.qc.ca</u></font></a>
<p><font size=3> </font>
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