[Gdal-dev] Maximum image size with PAux driver

[Frank Warmerdam]

Sébastien Grignard wrote:
> Hello All,
> I am assembling a couple of RGB Tiff images in one big PAux using the 
> gdal_merge.py utility, but the output image is incorrect. I suspect this 
> is due to its huge size : 133000x88000. I have already looked a bit in 
> the paux/raw driver code and changed the offset types to long long 
> without success...
> Do you have any idea of what could cause this ?


Sébastien,

I have briefly reviewed the PAux driver and no band can start after the 2GB
mark since signed 32bit integers are used  for the offset to the beginning
of the band data.

Since GDAL currently always creates band interleaved files, this is likely
your problem.  One solution would be to allow the band offset to be large;
however, I am a bit nervous about how to portably format, and atoi() large
integers.  I don't want alot of hassles with platform specific solutions
to this problem.  The other approach would be to add creation options to the
PAux driver so that you can create a line interleaved or pixel interleaved
data file.  Even though larger than 4GB the bands would start within the
first 2GB so there should be no problem.

Let me know if you would like a patch for this.

Best regards,

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