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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Runtime problem gdal:polygonize processing algorithm
I have a c. 60 MB file containing the GTOPO30 30-arc second (c. 1 km) digital elevation model of Africa. The dataset is described here: https://databasin.org/datasets/2965da954b114ff3b47621e99e3b29ba.
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Converting raster to polygon through ModelBuilder?
I have a set of raster which I want to convert to the polygon.
Below is the model I prepared, but its showing below error.
I checked the error code, which explains Alter the name to remove any ...
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Custom vector data drawing
I'm trying to create a map for a fictional map. I'm using Leaflet to display the map, with tiles, different levels of zoom and so on.
Now I need to generate, to "draw", some vector data. Specifically,...
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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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QGIS is flipping my rasters when I vectorize them
I am using QGIS to vectorize some raster layers. I was able to do this fine a week ago, but now every time I use the vectorize tool, the resulting vectors are flipped upside down. Any suggestions?
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Telling gdal_polygonize.py how to interpret colors / what does the `DN` field mean
I have lots of raster files I am converting to polys with gdal_polygonize.py. All these images have a consistent palette which I'd like to map to an attribute in the resulting polygons.
On most ...
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Generate multiple polygons based on JPEG image?
I have a number of image files depicting polygons (the original shapefiles are lost). Is there a way to automatically create new polygons in GIS, based on the form of the shapes visible in the image?
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Load GeoTIFF band value into PostGIS
I am trying to upload a geoTIFF file into my PostGIS database. Using raster2psql, it works.
raster2pgsql -I -C -M *.tif -F -t auto mytablename > mytable.sql
psql -d mydatabase -f mytable.sql
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Refine Raster Layer / remove Color bleeding
I have a Raster layer of Population density in a low resolution.
These raster layer has color bleeding between the different population areas. Is there a way, to remove them in QGIS like color ...
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Finding external boundary of bunch of vectors (using R libraries)
I have vectorized raster as in the image. This is actually 1419 polygons in SpatialPolygons class object.
I'm looking for a method which would allow me to extract the one most external polygon (...
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Converting historic map data (raster) into polygon format? [closed]
How do I convert historical buildings from map data (raster) into a polygon format?
The historic maps that I am referencing are the Sanborn Fire Insurance Maps. Here is the link to an example in case ...
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Digitizing contour lines from a picture in QGIS
I have a map with isobaths (water depth), like in this picture, and I would like to digitize them. Is there any tool or procedure in QGIS that can recognize the lines in the picture and create a ...
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Polygon to Raster conversion: Raster shifted ~10m horizontally. How to fix?
I converted a number of polygons into a raster. The cell size is correct but the raster has shifted ~10m horizontally.
Is there an issue with my method or is there a tool I can use to fix this?
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Extracting GeoTIFF colours and adding to equal geometry shapefile
I have the following map in .png-format that I would like to replicate, but I cannot obtain the original data.
The map shows the current water supply vulnerability for local municipalities in South ...
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Loading georeferenced map TIFF image into shapefile using ArcMap?
I need to add this Lake County townships map into a shapefile that contains other counties' townships. The shapefile's fields are: Township, Shape, Shape_Length, Shape_Area and County.
How can I do ...
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