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<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Funny, I made it nodata = 1 and the zero moved to second place.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><img width="317" height="151" style="width:3.3in;height:1.575in" id="Picture_x0020_1" src="cid:image002.jpg@01D603C5.0A070080"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> Even Rouault <even.rouault@spatialys.com>
<br>
<b>Sent:</b> Thursday, March 26, 2020 8:47 PM<br>
<b>To:</b> gdal-dev@lists.osgeo.org<br>
<b>Cc:</b> Joaquim Manuel Freire Luís <jluis@ualg.pt><br>
<b>Subject:</b> Re: [gdal-dev] Issue with writen colortables<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:9.0pt;font-family:"Courier New"">On jeudi 26 mars 2020 19:58:52 CET Joaquim Manuel Freire Luís wrote:<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">> images created with GMT but via GDAL.<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">> The .tif file looks right but if look at the .png (it needs lots of zoom) we<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">> can see that the top left pixel is missing. That happens, I think, because<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">> the transparency column has a first value of 0 whilst all the others are<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">> 1's. I checked this both with<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-paragraph-type:empty;-qt-block-indent:0">
<span style="font-size:9.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">You should probably not set the nodata value to 0. This will cause the alpha component for entry 0 of the color table to
be set to 0 when writing PNG<o:p></o:p></span></p>
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<span style="font-size:9.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">Even<o:p></o:p></span></p>
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<span style="font-size:9.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
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<span style="font-size:9.0pt;font-family:"Courier New""> <o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">--
<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New"">Spatialys - Geospatial professional services<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;-qt-block-indent:0;-qt-user-state:0"><span style="font-size:9.0pt;font-family:"Courier New""><a href="http://www.spatialys.com">http://www.spatialys.com</a><o:p></o:p></span></p>
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