[gdal-dev] Problems with reading large NITF files

[Frank Warmerdam]

Sophia Parafina wrote:
> I'm reading large nitf files (>2gb) with gdal and it seems to only read 
> the upper left hand corner first, then it seems to perform a second pass 
> which reads the entire file.  You can see this behavior in openev.
> 
> The problem I'm having is that I'm using gdal_translate to read the 
> file, I call gdal_translate from java and it seems to return that the 
> file has been read, but it only seems to read the upper left hand 
> corner.  Am I crazy of is gdal using 2 passes to read a large nitf file?

Sophia,

OpenEV sometimes does a prepass to get a rough histgram so it's behavior
can be fairly variable.

But gdal_translate (for a one band file) should just read top to bottom.

The problem sounds a bit like you might have built GDAL without large file
support.  If that happened, it would not (generally) successfully read
past the 2GB mark and for some drivers it might not even realize that it
isn't working properly.  What platform is this on?

In the configure results you are looking specifically for this item:

   checking for 64bit file io... yes

In particular, getting 64bit io enabled on exotic unix operating systems
can be a bit of a hassle.

Best regards,
-- 
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