Questions tagged [vectorization]
The conversion of raster data (an array of cell values) to vector data (a series of points, lines, and polygons).
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Converting image of map into vector format [closed]
What is the best way of converting a gif of a map into a vector format, such as a shapefile?
The only relevant parts that I am interested in are the outline of the island so I realize some manual ...
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Creating polygon with extents of raster file in QGIS
I have a tiff image file and want to get a polygon with the extent of the tiff.
Is there a direct way of doing this?
Right now I have to convert the image to vector (with gdal_polygonize) and then ...
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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 ...
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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) ...
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Converting raster to vector by generating center lines?
I have a binary raster containing boundary pixels with the value 1 (white) and no-boundary pixels with the value 0 (black):
I would like to vectorize the raster by keeping one center line trough the ...
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How to convert float raster to vector with python GDAL
I have float raster and now I want to convert it to vector. How is it possible with the Python GDAL library?
I have tried with gdal_polygonize.py of GDAL utilities on the command line and it worked ...
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Tools for importing historical maps into modern GIS systems?
What tools exist to derive geometries for use with modern GIS systems from older scanned maps?
I am referring more to libraries that generate actual data rather than present an interface for ...
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How to "clean" and vectorize a raster map?
I'd like to make use of a geological map as shown in the example below, which is only a pretty small and downsized part of the map, so editing/redrawing doesn't seem to make sense in the end.
My idea ...
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Spatial statistics tools : clustering analysis on raster data
I've an apparently simple problem, but i can't find a clear methodology to use.
I'm tasked to delimit "urban areas" by vector convex polygons, using the Gridded Population of the World dataset from ...
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Creating vector (with lines/polygons) from raster based on paper map in QGIS
For a task I have several maps created with GIS that look like the following:
I am mainly interested in the colored zones that aren't roads (red) or rivers (blue) and would like to turn these into ...
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Scriptable alternative to ArcScan (particularly vectorising lines within tolerances)?
Sadly the answer to Can you access ArcScan from a python script? suggests that it is not possible to script ArcScan from within a python script.
Therefore, does anyone know of any alternatives to ...
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Estimating resolution of vector data?
I got an old vector dataset with polygons covering a continent. The data was first published on paper at scale 1:5 000 000 and was later digitalized. I don't have the original data and no information ...
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Creating a seamless vector dataset from raster with gdal, R or Python
I'm trying to create a seamless vector dataset from an integer raster. "Seamless" as in: not gaps between features and no overlapping features.
The tools gdal_polygonize, pkpolygonize, terra:...
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Selecting and extracting data from TIFF files
I have some tiff files (2 for example) and a shapefile.
The real format of the tiff files is geoTiff.
I want to get the points inside the shape boundary. Each point should have 4 parameters: geom(...
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Simplification by constrained anti-aliasing in PostGIS
I vectorized a raster data set, therefore, I'm facing a "steps" effect, or aliasing, due to the fact that the vectorization strictly follows the raster cells. So, the geometry is quite large ...
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