[Gdal-dev] Format limitations in 64-bit architecture

[Frank Warmerdam]

Simon Perkins wrote:
> Thanks Frank for taking the time to actually look at the code... So, 
> there's no reason in theory why MEM and NITF can't support files larger 
> than 4GB (assuming a 64-bit OS in the case of MEM), but right now the 
> drivers are not capable of doing that.

Simon,

Right.  I might be able to fix and test the MEM driver assuming my AMD64
has enough swap space.  If you want to file a bug on it, that would be
helpful.

> I would think that there's a particular need for the NITF support to be 
> fixed up - I've seen several NITF files larger than 4GB - though I don't 
> unfortunately have any to hand that I could lend you for debugging. 
> Anyone out there have one they could lend to Frank? Or does someone have 
> NITF creation software that could be used to make such a file?

Well, in fact the changes aren't that complicated.  If you, or someone else
has a large NITF file that doesn't currently work, I could prepare a fix, and
then have you test it.  No need to transport/release the file to me.  But
the first step is to figure out if it currently works for the large file.
In fact, for an image file with one image that starts before the 4GB (or
perhaps 2GB) mark, but extends past the 4GB mark it would likely still work.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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