Frank Warmerdam wrote:
Is there any mechanism currently for creating overviews? How have you been testing overviews?
Frank, I suppose you are asking for the GDAL driver. However, just to confirm, gdal2wktraster can generate WKT Raster datasets with overviews (in regular blocking mode).
Under DOUBTs you ask what happens if the bounding box of a block does not match any real block in the table, what should happen. In this case IReadBlock() should fill the buffer with the nodata value (zero if nodata is not set).
This is exactly what gdal2wktraster does when tiles (blocks) of downsampled rasters have to get some padding along right-most or bottom-most column: http://trac.osgeo.org/postgis/browser/spike/wktraster/scripts/gdal2wktraster.py#L801 Certainly, it's client's (or perhaps GDAL driver too) responsibility to clip padded tiles and remove such areas of invalid raster data.
You also mention a doubt about how to handle the 16BF type, which is apparently "16-bit float". I have never seen such a thing before and I'm not sure why it is part of the WKTRaster specification. I would suggest removing it.
I had same impression and I simply don't use this data anywhere in gdal2wktraster script. I believe the right person to ask about this 16-bit float type is Sandro (strk) - he is the author of original specification documents: http://trac.osgeo.org/postgis/browser/spike/wktraster/doc Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
