[GRASS-user] filtering raster clumps before r.to.vect

Hi,

From a classification process we are developing, we created a

unsupervised classification from the image. We then want to select
random locations from the unsup raster as a training area for the 2nd
level of classification. I think it can be done by: r.to.vect,
v.random, v.extract. The problem is r.to.vect reports an out of
memory when converting the whole region. I tried r.neighbors to to
reduce 2-3 pixels clumps. Probable solution would be r.to.vect at a
smaller region then v.overlay. Is there a more straighforward way?
Like filtering the raster to include only large clumps from a randomly
selected points before r.to.vect?

cheers,
maning

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On Wed, Jun 4, 2008 at 1:01 PM, maning sambale
<emmanuel.sambale@gmail.com> wrote:

Like filtering the raster to include only large clumps from a randomly
selected points before r.to.vect?

You can try r.neighbors with method=mode and play with the size
parameter.

Markus