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<div class="moz-cite-prefix">Le 21/05/2025 à 20:53, Abel Pau a
écrit :<br>
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cite="mid:PAXPR07MB777564031052C02146D85593FA9EA@PAXPR07MB7775.eurprd07.prod.outlook.com">
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Okay, thanks!</div>
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So the interpretation we are aiming for is option <b>a)</b>:<br>
Each band is treated independently, and each one has its own
NODATA value. The NODATA value of one band is unrelated to that
of the others.</div>
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That said, the question is whether this behavior is consistently
supported across all formats, or if it only works this way in
our custom implementation.<br>
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<p>GDAL core (and most algorithms) should work fine, but if you want
to convert to GeoTIFF or COG, they only support the same nodata
value for all bands (although we could potentially extend the
GDAL_NODATA tag to support one value per band, but that would be
debate for another thread), and the same band type for all bands.<br>
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If not, perhaps the more robust approach would be to separate
bands with different NODATA values into different subdatasets.</div>
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<p>That's a possibility indeed. I'm not sure any implemented format
has done such effort, but there is nothing inherently wrong if you
want to do that.<br>
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<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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