[gdal-dev] gdalbuildvrt, gdal_translate, and MODIS HDF files

[Even Rouault]

Le mardi 03 mai 2011 15:34:16, Jose Gomez-Dans a écrit :
> Hi,
> 
> > > > I have recently come across the mosaicking magic that is 1) build a
> 
> vrt
> 
> > > > usin gdalbuildvrt and then 2) gdal_translate the vrt to whatever
> 
> format
> 
> > > > I want -- I'm noticing this is a crazy-fast way to do mosaicking
> > > > compared
> 
> I had a similar question on this a while ago, and one thing you have to be
> wary about is that the HDF libraries usually have a finite number of HDF
> files open simultaneously (see <http://trac.osgeo.org/gdal/wiki/HDF>). If
> you plan on using more than (say) 32 files simultaneously, you'll need to
> recompile the HDF library.

There should be no problem assembling more than 32 files in a VRT while keeping 
the number of files opened simultaneously below a certain threshold.

By default, it is set to 100. But you can change it by setting the 
GDAL_MAX_DATASET_POOL_SIZE configuration option/environment variable to another 
value, e.g. 30 in your case.


> 
> Jose