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<p class="MsoNormal"><span lang="EN-GB">Hello, I am using GDAL version 3.6.2 to make a Hillshade map from an elevation map (tif) using the gdaldem command.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">My question is because I need the background of the image generated with the previous command to be transparent,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I have tried different ways but it usually gives me this error:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">ERROR 1: Error: band 1 has no color table<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">These are the commands I have tried:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">gdal_translate -b 1 -b 1 -b 1 -b 1 -ot UInt16 --> Generates image with four bands, but all in white<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">gdal_translate -co PHOTOMETRIC=RGB -co ALPHA=YES--> gives ERROR1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">gdal_translate -expand rgba --> gives ERROR1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">gdalwarp -dstalpha -->creates an image with a transparent background with two bands, but AUTOCAD does not recognize it well and considers the entire image transparent and not just the background.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Could you give me any solution? <o:p></o:p></span></p>
<p class="MsoNormal">Thanks and regards.<o:p></o:p></p>
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