All Questions
Tagged with vectorization grass-gis
15
questions
0
votes
0
answers
143
views
How to convert raster to vector by generating center lines?
I need to vectorize the raster by keeping one center line trough the boundary pixels. My solution would need to be very similar to this question: Converting raster to vector by generating center lines?...
- 1
0
votes
0
answers
47
views
Why r.to.vect process takes too much time with topology analysis?
My task is to vectorize a standard landuse map (PROBA-V discrete classification) for extent 118.747182 54.231218 124.946218 60.060467 degrees. Raster is too detailed for me, so I generalize it.
I use:...
1
vote
1
answer
130
views
Issues with vectorisation of thinned flow accumulation through r.to.vect on QGIS
I'm trying to produce a shapefile river network from a flow accumulation raster using the r.to.vect function and I've overcome some difficulties regarding bit depth and thinned raster.
n.b. I don't ...
- 339
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votes
1
answer
271
views
r.thin (GRASS) not giving correct result
I have raster image of road feature. I want to extract line feature from it. So I run r.thin tool on it of parameter -
{ 'GRASS_RASTER_FORMAT_META' : '', 'GRASS_RASTER_FORMAT_OPT' : '', '...
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answers
57
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v.surf.idw raster file conversion into a vector with same colours style
Is it possible to convert from raster to vector the raster file resulting from grass interpolation algorithm "v.surf.idw" coloured with the quantile method and maintain such colours in the vector file ...
- 161
1
vote
0
answers
177
views
Grass GIS table creation error during r.to.vect
When I execute r.to.vect the following error appears:
r.to.vect input=sreviLC815109_-120_-120 output=temp feature=area --o --q
DBMI-DBF driver error:
ERROR: Unable to create table: create table temp ...
- 901
1
vote
0
answers
63
views
Grass GIS r.to.vect: Prevent neighboring cells with equal values from being unified
I've got different satellite image bands as GRASS rasters, which I want to convert to vector dataset. As I want to compare the IDs of the cell polygons later on, the neighboring cells with ...
- 901
2
votes
3
answers
638
views
Grass GIS: ArcGIS' "Raster to polygon" equivalent
I've got a small clipped extent of a LANDSAT image and I need to have the single pixels as polygons in order to tell the overlap proportions of overlaying polygons.
In ArcGIS I used "Raster to polygon"...
- 901
1
vote
0
answers
140
views
Convert manual colored maps to vector
Is there a way to colorimetrically and automatically vectorize georeferenced rasters that came from manually colored, scanned maps? Currently we Print the topography maps 20k scale --> hand-coloring ...
- 271
2
votes
1
answer
223
views
Preserving polygon boundaries when vectorizing raster according to polygon vector? [closed]
I have a raster which I clip by some polygons and then convert to polygon. I would like to obtain the same number of polygons in both my vector files.
The problem is that some areas in the vector ...
- 3,785
7
votes
1
answer
927
views
Generalize large polygon-file
I have a large polygone file with landuse information (6 classes). Its vectorised from a raster classification so the polygons are all angular. Any of my tries to generalize with v.generalize (sneaks, ...
- 8,338
15
votes
2
answers
7k
views
How to smooth large vector polygons from Raster
I have a landuse classification raster file (6 classes) of a large area. But I need it in vector polygons so I vectorised it. No problem so far, but the result is - of course - that every pixel is ...
- 8,338
13
votes
5
answers
6k
views
How to generalize and vectorize a LandUseClassification raster file?
I want to vectorize that rasterfile with its 6 landuse classes. The classification is very noisy and have to be generalized before.
The result should be a polygone vector file.
I use SAGA, (GRASS) ...
- 8,338
2
votes
2
answers
540
views
River drain: r.watershed to vector is not working
I want to vertorize the result of r.watershed (accumulation). After using r.to.vect I got the message that I have to use r.thin before. So I did, but the message comes again and again.
What I am ...
- 8,338
4
votes
2
answers
4k
views
How to vectorize a Raster-Classification? (QGIS, GRASS)
I classified my raster-DHM into elevation levels using colormap. Its not a "real" classification, just a colormap. So I can't vectorize the classes to get polygons for every class.
What's the best ...
- 8,338