[udig-devel] Re: [Geotools-gt2-users] How to open a large tiff

[Andrea Aime]

Adrian Custer ha scritto:
> Hey all,
> 
> I'm trying to digest a 1/2 global land cover tiff. The source is:
> http://earthobservatory.nasa.gov/Newsroom/LCC/
> and the specific file is
> http://earthobservatory.nasa.gov/Newsroom/LCC/Images/lcc_east_1km.tif
> 
> nothing on my machine can open this file. Is there a way to add the
> location information to the file so uDig can open it? Also, is there a
> way to pre-tile the file into one of those image pyramids I keep hearing
> about? 

With current uDig, you'll have hard times, 25MB is a bit big for it,
give it plenty of memory. And you have to write a .tfw file for it,
see some docs here:
http://www.omg.unb.ca/~jonnyb/processing/geotiff_tifw_format.html
http://www.gdal.org/frmt_various.html#WLD

In the future, with a uDig that uses geotools 2.3.x or trunk, it's going
to be relatively quick, especially if you do use gdal_translate to pre 
tile it, and gdaladdo to add overviews to it.
Pyramids, forget about them, the pyramid generator is broken at the 
moment, but besides this, you don't need a pyramid for such a "small" 
file (it's only 25MB).

Cheers
Andrea