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<p class="MsoNormal"><span lang="EN-US">Attached are two tinny indexed images created with GMT but via GDAL.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The .tif file looks right but if look at the .png (it needs lots of zoom) we can see that the top left pixel is missing. That happens, I think, because the transparency column has a first value of 0 whilst all the others
are 1’s. I checked this both with GDAL and Matlab.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The code that writes it is <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><a href="https://github.com/GenericMappingTools/gmt/blob/master/src/gmt_gdalwrite.c#L343">https://github.com/GenericMappingTools/gmt/blob/master/src/gmt_gdalwrite.c#L343</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">where .c4 is well set to 255. However when it lands on the file, the first was converted to 0.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Again, I’m doing this the Julia bindings so have no C code to provide a MWE.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><img border="0" width="118" height="277" style="width:1.225in;height:2.8875in" id="Picture_x0020_1" src="cid:image003.jpg@01D603A8.F88800A0"><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Joaquim<o:p></o:p></span></p>
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