[GRASS-user] raster to vector conversion

Hello,

I am wondering if there is a way to convert raster to vector in GRASS without the smoothing. I want to keep the “blocky” look of the raster boundaries to their original pixel extents. I find too much detail is lost with the smoothing. Are there any other open source methods to do this if not in GRASS. Thanks !
Tom

from the GRASS help: “To produce a better-looking vector map, r.to.vect smoothes the corners of the vector data as they are being extracted. At each change in direction (i.e., each corner), the two midpoints of the corner cell (half the cell’s height and width) are taken, and the line segment connecting them is used to outline this corner in the resultant vector map. (The cell’s cornermost node is ignored.) Because vectors are smoothed by this program, the resulting vector map will not be “true” to the raster map from which it was created. The user should check the resolution of the geographic region (and the original data) to estimate the possible error introduced by smoothing.”

Tom Miewald wrote:

I am wondering if there is a way to convert raster to vector in GRASS
without the smoothing. I want to keep the "blocky" look of the raster
boundaries to their original pixel extents. I find too much detail is lost
with the smoothing. Are there any other open source methods to do this if

from the GRASS help: "To produce a better-looking vector map,
*r.to.vect*smoothes the corners of the vector data as they are being
extracted.

It only does this if you use the -s flag; otherwise, you get hard
corners.

--
Glynn Clements <glynn@gclements.plus.com>