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<p class="MsoNormal">Hi List,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using GDALAutoCreateWarpedVRT() to warp datasets which then get transformed to bitmaps. When warping images sometimes they get rotated leaving black around the edges of the resulting image (especially when warping to another UTM
zone). How can I produce images without the black edges? As far as I can tell, GDAL won’t probuce bitmaps with alpha layering. I have read about GDAL’s noData masks but
<span style="color:#1F497D">am</span> having trouble figuring out how to produce them. They would work well because I don’t need opacity I just want to mask out the black edges
<span style="color:#1F497D">when I display the </span>bitmaps.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Jeremy<o:p></o:p></p>
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