<div dir="ltr">I have never tried it but I think this may be what you are looking for  (with the -setalpha flag)<br><br><a href="https://gdal.org/programs/nearblack.html#nearblack">https://gdal.org/programs/nearblack.html#nearblack</a><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, 3 Oct 2022 at 21:23, <<a href="mailto:liglio.pessoal@nexxa.com.br">liglio.pessoal@nexxa.com.br</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg292977749392577352"><div lang="PT-BR" style="overflow-wrap: break-word;"><div class="m_292977749392577352WordSection1"><p class="MsoNormal">Hi,<u></u><u></u></p><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal"><span lang="EN-US">I have a PNG image RGB (3-band), and I want to set the background transparent. How do I do it  using GDAL ?<u></u><u></u></span></p><p class="MsoNormal"><span lang="EN-US"><u></u> <u></u></span></p><p class="MsoNormal"><span lang="EN-US">Regards,<u></u><u></u></span></p><p class="MsoNormal"><span lang="EN-US"><u></u> <u></u></span></p><p class="MsoNormal"><span lang="EN-US">Liglio<u></u><u></u></span></p><p class="MsoNormal"><span lang="EN-US"><u></u> <u></u></span></p></div></div>_______________________________________________<br>
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