[Gdal-dev] GDAL raster output to GE Add -> Image overlay ...

[Roger Bivand]

Hi,

Does anyone have any experience of outputting rasters for adding as image
overlays to Google Earth? I have success with a Byte type GTiff (just
integers in the 0-255 range), but have to type the bounding box into the
form directly. 

Attempts to set an alpha channel crash GE when reading the file (it does
say alpha only with PNG, so I'm not surprised - my GE 4.0.2413 (beta) on
RHEL). I have not tried an RGB GTiff yet. Because PNG is a CreateCopy, and
we've used Create in writing from R, I haven't tried that route yet. The
target is to provide gridded interpolations in a readily distributable
format for users without access to GIS.

Thanks for any insights,

Roger

PS. Trial single band file at:

http://spatial.nhh.no/misc/grey.tif

is IDW of Meuse bank zinc ppm soil pollution, with bbox:

       min     max
s1  5.7209  5.7649
s2 50.9555 50.9879


-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no