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<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black">Seems like this is a straightforward issue but finding it difficult to solve online.<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black">I have a new crop of 4-band orthoimages, as GeoTIFFs. I want to create mosaics of some tiles. There is a slight pixel overlap at the edges. When I run gdalwarp it always treats
the 4th band as alpha, which causes the overlap edges to be lighter than everything else in the mosaic, creating an odd grid pattern were these edges were (when viewing the CIR bands 4-1-2).<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black"> <o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black">How can I disable this treatment of the 4th band as alpha?<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="color:black">===============================<br>
</span><b><span style="font-size:10.0pt;font-family:"Calibri","sans-serif";color:black">Michael Smith MS GISP</span></b><span style="font-size:10.0pt;font-family:"Calibri","sans-serif";color:black"><br>
State GIS Manager, Maine Office of GIS<br>
State of Maine, Office of Information Technology<br>
michael.smith _at_ maine.gov<br>
207-215-5530<br>
<br>
Board Member, Maine GeoLibrary<br>
Board Member, Maine GIS Users Group<br>
State Rep, National States Geographic Information Council<br>
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<br>
</span><span style="font-size:10.0pt;font-family:"Calibri","sans-serif";color:black">***NOTE NEW ADDRESS***<br>
<br>
</span><span style="font-size:8.0pt;font-family:"Calibri","sans-serif";color:black">State House Station 145<br>
51 Commerce Drive<br>
Augusta, ME 04333-0145<br>
69<sup>o</sup> 47' 58.9"W 44<sup>o</sup> 21' 54.8"N</span><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black"><o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:black"><o:p> </o:p></span></p>
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