[gdal-dev] Raster algebra with Gdal and Python

[Mateusz Loskot]

Zoltan Szecsei wrote:
> Alexander Bruy wrote:
>> Hi again,
>>
>> with your help I've fix problem with "integer overflow" and now I get
>> correct results.
>>
>> Also I clean up my code for reduce memory usage but problem with large 
>> files is
>> remain. I have raster with size 11779*10663 and 5 bands. When I 
>> calculate NDVI
>> on Linux box (2 Gb RAM, 2Gb swap, GDAL 1.6.3) all works fine and I get 
>> correct
>> results.Peak memory consumption during this operation is 1900 Mb RAM and
>> 300 Mb swap (monitored with htop).
>>
>> When I run same code with same raster on Windows box (2 Gb RAM, swap 
>> size is
>> selected by OS ~1.3 Gb, GDAL 1.6.3) I get MemoryError. Peak memory 
>> consumption
>> during this operation is 600 Mb RAM and 700 Mb swap. I've try smaller
>> raster with size
>> 8500*7600 pixels but get MemoryError too.
>>
>>   
> Hi,
> I'll bet the problem is that you are hitting the normal 2GB user address 
> space in Windows.
> Google for "/3GB" and you will find how to increase this to 3GB.

http://blogs.msdn.com/oldnewthing/archive/2004/08/16/215089.aspx

http://blogs.msdn.com/oldnewthing/archive/2004/08/22/218527.aspx

Best regards,
-- 
Mateusz Loskot, http://mateusz.loskot.net