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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Fastest way to clip millions of small polygons and storing results as JSON [closed]
I have a dataset with couple million farm polygons (around 2.5 million and only expected to grow in the future), and I need to calculate the NDVI for these farm polygons, with some basic stats (...
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Convert a PNG file to a line layer in QGIS
I have a map in PNG-format that looks like this:
I have imported it into QGIS as a raster. I want to create a line layer as a network based on the blue and pink lines. Is there a way to create a line ...
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Converting vectorization (raster to vector) with small steps in values in QGIS
I have a raster file that contains water depths in m. The water depths are the only attribute and should be transferred to the vector layer.
The raster files have a cell accuracy of 1m x 1m. I would ...
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Extract a vector from a raster with a single boundary in QGIS
I have a "problem", I need transform a raster in a vector and it works but some pixels like the one in the print it is separated from the boundary, and for my use (a specific use of ...
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ReducetoVectors in Google Earth Engine not working with the Mollweide transformation. Need to calculate zonal statistics for global scale analysis
My study is a global-scale analysis of the factors driving forest gain, with grid cells as the unit of analysis. I need to calculate the amount of forest gain per ~65km2 hexagonal grid cell at the ...
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Generate points from raster image in QGIS
I'm hoping to generate a new vector file from select points from a raster image in QGIS. I don't know if it is possible.
For instance, I would like to generate a vector point file that puts a point ...
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Convert topographic map to vector and text
I have a topographic map in TIFF format and I vectorized it in QGIS (3.22.0). For my project I needed the settlements, which I was able to extract. More importantly are the names of the settlement. ...
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GEE Export individual FeatureCollections as shapefiles from an image Collection
I have run an NDWI index for an Image collection and thres holded the results, which I want to import as individual FeatureCollections (shapefiles).
My code is of course longer, but teh most importan ...
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Differentiate vertical and horizontal shapes
I have the following shape file:
Each polygonal area (the lines are areas) is one feature in a single Shapefile.
Can anyone think of a simple method that can be implemented with qgis to separate the ...
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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?...
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Abrupt error when trying to run model with viewshed as batch process
I am trying to run the following model as a batch process. In summary, I take a DEM raster layer and a number of individual points as separate .gpkg files in a directory (these points have been ...
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Smoothing a vector layer in Google Earth Engine
I extract riverbanks out of Landsat images at Google Earth Engine. After the vectorization of my raster image I receive a shapefile of the riverbank with many unwanted vertices. How can I smooth the ...
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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:...
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Chain the output of gdal_polygonize to ogr2ogr
I am doing a two step process:
Polygonize a PNG raster via gdal_polygonize.py
Add a custom field named id
Upload the resulting vector to PostGIS via ogr2ogr
I am currently doing it in two steps, ...
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Vectorizing all pixels as separate polygons using rasterio
I use rasterio.features.shapes and use the geometry of pixels in raster data to create polygons for each pixel. Pixels with the same value merge these pixels if they are adjacent.
What I want is for ...
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