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<font size="-1"><font face="Helvetica, Arial, sans-serif">I don't know
if it is my misunderstanding of the way the "no data" flag should be
handled, or if there is a bug in QGIS 1.40 (Linux) geotiff support.<br>
<br>
I have a 24-bit GeoTIFF image in which gdal_warp has set the 'no data'
flag as zero. When I display this image in QGIS, any pixel which has
*either* the red, green or blue value as zero is displayed as
transparent. I expected transparency only when all three values were
zero.<br>
<br>
You can see the geotiff files and jpeg screen captures at
<a class="moz-txt-link-freetext" href="http://gotslack.org/unisips/nodata">http://gotslack.org/unisips/nodata</a> .<br>
<br>
The file '0255.tif' does not have the no_data flag set (you can see
this in data.jpg), while the file 0255_nodata.tif has no_data set as
zero (nodata.jpg).<br>
<br>
Is this the expected behavior? If so, how can I display this image
with transparency only when all three values (RGB) are zero?<br>
<br>
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