Hi I have a GeoTIFF with this characteristics: - 6 bands - last band is "Alpha" (with values 0 or 255, nothing else) - Float32 - NoData value = -10000
The 5 first bands may have "nodata" pixels, not necessarily on all bands simultaneously. (nodata pixels are usually broken or saturated pixels from the sensor, and each band comes from a different sensor). The valid pixels have values between 0 and 1 When I try to generate embedded overviews (with average interpolation) with C++ or CreateCopy as COG (with default values), looks like it is using the -10000 values as valid values, and producing results in the overviews like -9990.6... that obviously are not anymore considered "nodata". The first noticeable effect opening the file in QGIS, is that the min and max value for each band are not anymore 0 and 1, but nonsense negative numbers. Can both Alpha and NoData live together properly? Thanks. PS I have the impression that with external ovr file it does not happen. I am testing more. .___ ._ ..._ .. . ._. .___ .. __ . _. . __.. ... .... ._ .__ Entre dos pensamientos racionales hay infinitos pensamientos irracionales.
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