[GRASS-user] How to convert multi-bands clusters in a vectorial

GRASS GRASS user
1

Greetings
(This may sound as a complicated question but it’s not :slight_smile: )

I have used an external tool to produce clusters from Landsat images. For each input bands, I obtain clusters with a desginated value (mean of the values in that cluster). So, if I use 4 bands, I obtained 4 outputs with clusters. in each image I obtain the same clusters but with different values (depends on pixel values). What I want to obtain is a single map (raster or vectorial) with all clusters. in GRASS, how can I “merge” this 4 bands in order to obtain a labeled product? it can be a single raster or vectorial but it has to be a single band/layer…

Thanks
(if needed, I can better explain this with an example)

Monica

2

On Tue, Jul 20, 2010 at 2:17 PM, Monica Buescu
<monicabuescu1985@gmail.com> wrote:

Greetings
(This may sound as a complicated question but it's not :slight_smile: )
I have used an external tool to produce clusters from Landsat images. For
each input bands, I obtain clusters with a desginated value (mean of the
values in that cluster). So, if I use 4 bands, I obtained 4 outputs with
clusters. in each image I obtain the same clusters but with different values
(depends on pixel values).

How did you do this? (which commands)?

What I want to obtain is a single map (raster or
vectorial) with all clusters. in GRASS, how can I "merge" this 4 bands in
order to obtain a labeled product? it can be a single raster or vectorial
but it has to be a single band/layer...
Thanks
(if needed, I can better explain this with an example)

Yes please :slight_smile:

Did you see
http://grass.osgeo.org/wiki/Image_classification
?

Markus

3

Hi there

I have used an external tool to produce clusters from Landsat images. For
each input bands, I obtain clusters with a desginated value (mean of the
values in that cluster). So, if I use 4 bands, I obtained 4 outputs with
clusters. in each image I obtain the same clusters but with different values
(depends on pixel values).

How did you do this? (which commands)?

I have used an external tool based on Segmentation paper. (coded in C++).

What I want to obtain is a single map (raster or
vectorial) with all clusters. in GRASS, how can I “merge” this 4 bands in
order to obtain a labeled product? it can be a single raster or vectorial
but it has to be a single band/layer…

Yes please :slight_smile:

Eheheeh here goes :slight_smile:
I have 4 bands and in each one pixel values are calculated based on band cluster mean. I mean, pixels included in a certain cluster, are all with the same value that correspond with average of pixels included in the same cluster. This happens in all 4 bands. What I want is to merge 4 bands in a single one in which I will have labeled clusters with an integer (1,2,3,4,5…) isntead of pixel mean.

How can I do this merge?

Thanks Monica