[gdal-dev] Raster from temporary tiles

[Matthias Kuhn]

On 20/07/16 08:20, Even Rouault wrote:

> Le mercredi 20 juillet 2016 08:08:07, Matthias Kuhn a écrit :
>> Hi Even
>>
>> On 20/07/16 08:04, Even Rouault wrote:
>>> Hi Matthias,
>>>
>>> The GPKG driver is a full-blown raster driver with similar capabilites to
>>> the GeoTIFF one. That is you can use GDALCreate() to initialize an empty
>>> raster and then write arbitrary portions of it with GDALRasterIO(, ...,
>>> GF_Write, ...).
>>> You can also initialize empty overviews with GDALBuildOverviews( ...,
>>> "NONE", ... ) and write arbitrary raster content in them with
>>> GDALRasterIO() on the overview bands.
>>>
>>> Even
>> Thanks, good to know it's possible!
>> Is that available in
>>
>>   * command line tools
> For creation of an empty raster, I can't think of an existing easy way.
> For creation of empty overviews, yes with
> "gdaladdo -r NONE your.gpkg 2 4 ...."
> For update of an existing raster, with "gdalwarp in.tif out.gpkg"
> For update of overviews, likely with
> "gdalwarp in.tif out.gpkg -doo ZOOM_LEVEL=2" (caution the zoom level is in the 
> GPKG meaning, and not with the GDAL convention. ie ZOOM_LEVEL=0 is the less 
> detailed overview level)
>
>>   * the python API
> Sure. The Python API wraps alls those basic calls
> driver_obj.Create()
> band_obj.WriteRaster()
> gdal.BuildOverviews()
>
> The driver tests might be a useful resource:
> https://svn.osgeo.org/gdal/trunk/autotest/gdrivers/gpkg.py
>
Awesome, thanks a lot Even!