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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QGIS .tiff to shapefiles by extracting colours
So I have the following raster file:
I would like to edit it so that I export all green, blue or purple areas as a single, new .tiff. Afterwards I would make a vectorization to be able to process the ...
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What are strategies to simplify a vectorized raster layer?
For a GIS web viewer I am building, I plan to use large sets of vector data on coral reefs (source: Allen Coral Atlas). When viewing the downloaded data, it seems that the original source was raster ...
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Create clipping masks using contour lines in QGIS
I'm new to QGIS and GIS in general. I'm trying to find a way to create height layers automatically and then use them to clip other layers.
In detail: Below is my area of interest. I have a raster ...
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Visualization and vectorizing for AI in Google Earth Engine
I'm glad to find this space, I come from a background in economics and do not know the first thing about GIS (hope to learn as I go with this project).
I found an interesting dataset (https://...
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Polygonize/Vectorize large raster
A raster(.tif) of 6.70GB needs to be converted into polygons. The raster is binary (0 & 1), currently I am using Polygonize (raster to vector) and its taking a considerable amount of time and the ...
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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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Extracting raster outline to a vector geometry
I have a raster data set with an irregular outline (every value outside is NaN) in Python (loaded from rasterio v.1.3a3 ):
I'd like to extract its outline to a vector shape, such as a Shapely ...
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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 ...
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How to transfer simple GeoTiff data into a database
I'm trying to turn a relatively simple GeoTIFF file into a dataset readable by an API.
End goal:
Build a GET method for an API like
/search_by_coordinates?lat=-73.1221&lng=44.4924 and get ...
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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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Converting Raster into Vector in QGIS
I am in process of converting one raster file ( JBA Flood score) into Vector file But due to raster size ( Possibly) process seems endless i.e. even after 9 hours process still continue. Is there any ...
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How to polygonize NDVI raster using GDAL?
I have raster with NDVI values. I would like to polygonize the raster to get vector where each polygon is a pixel.
I have tried gdal.Polygonize as described in the documentation and that runs without ...
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Contour Polygon Alternatives on QGIS
I am trying various ways to make polygons from raster data using 1 m DEMs. I am using QGIS 3.16 Hannover I have tried vectorizing my data, which does work OK, but I would like smoother boundary lines ...
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Symbol recognition on a scanned image (map)
I have a specific task and I'm looking for possible approaches. What I'm trying to do is this:
I have a high resolution (600dpi) scanned, and georeferenced image of a map, and I need to be able to ...
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Seeking GIS tool to automatically extract polygon geometries from images
Let's say I have multiple png images like the following one:
I'd like to find a way where I can automatically draw polygon geometries on this image. Something like the following:
My expectation is ...
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