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<p class="MsoNormal">Hi Sean,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The background is actually not transparent : ) Just for your reference, I followed the following post and removed the background:<o:p></o:p></p>
<p class="MsoNormal"><a href="https://stackoverflow.com/questions/765736/using-pil-to-make-all-white-pixels-transparent">https://stackoverflow.com/questions/765736/using-pil-to-make-all-white-pixels-transparent</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for your help on my question!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Guodong<o:p></o:p></p>
<p class="MsoNormal"><b>From:</b> gdal-dev <gdal-dev-bounces@lists.osgeo.org> <b>
On Behalf Of </b>Sean Gillies<br>
<b>Sent:</b> Friday, March 6, 2020 1:22 PM<br>
<b>To:</b> gdal dev <gdal-dev@lists.osgeo.org><br>
<b>Subject:</b> Re: [gdal-dev] Using Python gdalwarp to read gif file and world file, re-project to another picture<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Guodong,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Thu, Mar 5, 2020 at 2:16 PM Guodong Zhu <<a href="mailto:gd.zhu@outlook.com">gd.zhu@outlook.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Sean,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks a lot for your answer! It works for me. I have one follow up question: is there a way to make the background transparent instead of being white?
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I really appreciate your help!<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The background is transparent, I think it may appear white due to details of your image viewer. If you convert the warped GeoTIFF to a PNG like<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">gdal_translate -of PNG warped.tif warped.png<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">you'll have a file that looks properly transparent in a browser or image viewer.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Sean Gillies<o:p></o:p></p>
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