[GRASS-user] Nodata & r.thin

[Nicolas Devaux]

Hi all, is it possible to recode Nodata cells in a raster map?
How does r.thin handle Nodata value cells? In my case,  it changes 
Nodata value cells of the original raster (surrounding cells obtained 
after the georeference operation of a scanned map) to the value 1. 
Hence, I get a message error when I try to use r.to.vect command because 
of these surrounding cells that have the value 1 instead of Nodata and 
that constitute an area instead of a simple line.

thanks for any help....