On Monday 21 July 2008, milton ruser wrote:
Dear all,
I have a very large BINARY image (60,000x50,000 pixels) and need to
generate the distance map from the 1 values.
When the images are small than my image, I can generate the distance map
using ArcGis (my image is in .IMG format), but ArcGis return error for this
large one.
I am running R 2.7.1 under windows/xp. Is there a way of do this job using
R ou RSaga? (unfortunately I don?t have GRASS installed), and my
experience with RSAGA is near zero. My computer is 4GB ram. I can load the
images on ArcGis and Erdas without problem, but I only don?t know how do
this task.
Try and use GRASS. It is made for these types of operations. Since R is
memory-bound (for most practical purposes) a sequential-access approach like
GRASS should work much better. There is a windows installer for GRASS, or you
can just install the latest QGIS: this comes with GRASS!
Cheers,
Dylan
--
Dylan Beaudette
Soil Resource Laboratory
http://casoilresource.lawr.ucdavis.edu/
University of California at Davis
530.754.7341