[gdal-dev] Issue with writen colortables

[Joaquim Manuel Freire Luís]

Attached are two tinny indexed images created with GMT but via GDAL.
The .tif file looks right but if look at the .png (it needs lots of zoom) we can see that the top left pixel is missing. That happens, I think, because the transparency column has a first value of 0 whilst all the others are 1's. I checked this both with GDAL and Matlab.

The code that writes it is
https://github.com/GenericMappingTools/gmt/blob/master/src/gmt_gdalwrite.c#L343
where .c4 is well set to 255. However when it lands on the file, the first was converted to 0.

Again, I'm doing this the Julia bindings so have no C code to provide a MWE.


[cid:image003.jpg at 01D603A8.F88800A0]

Thanks

Joaquim
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