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<DIV><SPAN class=296491402-22032006><FONT face=Arial size=2>Hi
there,</FONT></SPAN></DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial size=2> I am totally
new in this forum and I am just a GeoTIFF user. Now I have to process GeoTIFF
imagery and have some general problems.</FONT></SPAN></DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial size=2> I have to
process a number of tiles and have to identify no data areas. The TIFF images
are 24BIT and the "no data" area is a black and a WHITE area in a
tile.</FONT></SPAN></DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial size=2> I would like
to identify all tiles (filenames), which have a cluster of at least 4 pixels in
one (white) or the other (black) color. </FONT></SPAN></DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial size=2> I tried to
find a way using gdal, but was not successfully. May somebody has an idea to
process the GeoTIFF imagery.</FONT></SPAN></DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=296491402-22032006><FONT face=Arial
size=2>Cheers</FONT></SPAN></DIV>
<DIV align=left>
<P align=left><FONT face=Arial><FONT color=#000080><FONT size=2><STRONG>rainer
spittel</STRONG></FONT></FONT></FONT></P></DIV></BODY></HTML>