[Gdal-dev] Several questions

[Frank Warmerdam]

Romano J M Silva wrote:
> What is this caching limit?

Romano,

The default caching limit is currently 10MB but was 5MB up until
recently.  It can be controlled by various means, including the
GDAL_CACHE_MAX environment variable (set it to a cache size in bytes).

> I am commonly loading small window of data in a scanline mode. Is it
> possible to  "create" a tiled GeoTiff?

It is possible to create a tiled GeoTIFF.  The following is an example
of using gdal_translate to convert an input file into a tiled GeoTIFF
image.

gdal_translate -of GTiff -co TILED=YES in.tif out.tif

> How do I retrieve an overview to get its bands?

The GDALRasterBand::GetOverview() method can be used to fetch overviews
of a given band.  The GetOverviewCount() method returns the number of overviews
available.  There are C and Python analogs of course.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent