[gdal-dev] GDAL/OGR 1.8.1 Advance Warning

[Armin Burger]

On 29/06/2011 19:53, Even Rouault wrote:
> Le mardi 28 juin 2011 21:32:01, Armin Burger a écrit :
>> Frank
>>
>> a functionality that I would find useful in combination with clients
>> like ArcGIS or Erdas are the Erdas overviews in *.rrd files. When
>> creating overviews with gdaladdo using the "--config USE_RRD YES"
>> option, aux files instead of rrd files are created. They are not fully
>> recognized by ArcGis/Erdas, depending on the image format.
>
> I'm afraid I know very little of the subtleties of Erdas overviews, but I see
> that the HFA_USE_RRD config option can also be set to YES and produces a .rrd
> file. Perhaps this is was you are looking for.  See
> http://gdal.org/frmt_hfa.html . I've found also a past thread where this is
> somehow discussed : http://www.mail-archive.com/gdal-
> dev at lists.osgeo.org/msg00129.html

Even

thanks a lot for pointing me to the thread. I was not aware of this 
double option
  --config HFA_USE_RRD YES --config USE_RRD YES

since the documentation and the --help of gdaladdo just mention the 
USE_RRD option, which puts the overview inside a single big .aux file. 
It looks a bit like the small .aux file created with the 2 config 
options contains also image statistics, but I will check this tomorrow 
at work.

Armin