Questions tagged [vectorization]
The conversion of raster data (an array of cell values) to vector data (a series of points, lines, and polygons).
165
questions
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22 views
Vectorizing large slope based raster dataset
I need to vectorize my slope rasters into polygons and currently I have tried reclassification-> raster to polygon but even for an area of 30x30 km, it created 1 crore 21 lacs of polygon and this ...
0
votes
1answer
27 views
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 ...
2
votes
0answers
33 views
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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27 views
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 ...
3
votes
1answer
169 views
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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0answers
14 views
Align polygon borders by underlying raster values
I have an interesting problem: I have polygon borders that correspond roughly to "value-boundaries" in a raster (areas where the raster values are clearly distinguishable between two areas).
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26 views
Draw polygon (vectorize) raster based on same colored pixels -- getting bad polygons
So, I have a TIF georeferenced map and a rather messy shape that I need to digitize. It is green but has a lot of holes in it that are light green color. So, I want to capture all green pixels and ...
2
votes
1answer
29 views
Scaling a soil profile Raster to georeference and vectorize Raster data
I have pictures of root patterns, where each root is marked by a point. We worked on soil profile walls, so there is no coordinate system to use as a basemap. I loaded it to QGIS and classified it ...
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32 views
Conceptual question on comparing rasterized data with vectorized (polygons) data
I've got this doubt on how to best proceed with the following situation: I would like to compare two datasets, one (model_data) is a raster (NetCDF format), with lat, lon and time as coordinates, ...
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38 views
Automatic extraction of ditches and breaklines from point clouds/ DEM
I am trying to automatically find Ditches and break lines from a point cloud of a rural but flat area.
So far I tried to covert LAS to DEM and generate 'streams' using Flow direction, Flow ...
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33 views
QGIS Polygonize algorithm, converting raster to vector files different from Mac and Windows
We are trying to convert a single-band raster files with values 0s & 1s to Vector. When using the QGIS's internal algorithm 'Polygonize', the result is slightly off from a Mac then the ones from ...
1
vote
1answer
88 views
Wrong features when exporting vectorized raster data to a file using GeoPandas after applying a filter and a dissolve operation
I have a raster file with black areas having a value of 0 and white areas having a value of 1, resulting from a visibility analysis:
I vectorized this raster after loading it with rasterio:
import ...
0
votes
1answer
22 views
Transforming a raster .png image to vector file
I have been working with FEMA flood maps to georeferenced and then digitize the maps by hand drawing polygons of the flood zone features. I have tried some workarounds to make the digitization process ...
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0answers
31 views
How is it that ArcMap and QGIS produce feature classes with different numbers of points and different coordinates from the same TIFF?
I have a 300m by 300m B&W TIFF map of Brazil, and I need to convert all the pixel values into a point feature class. When I do it in ArcMap using Raster to Point, I get a feature class with 92,054,...
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46 views
Google Earth Engine Reducing Landsat Global Inland Waters Raster to Vector
I'm trying to create a vector outline of the water areas of the Landsat Global Inland Water raster in Earth Engine. I get the error "Line 3: water.addBands is not a function" from the ...
2
votes
2answers
191 views
Vectorizing raster with values between 0 and 1 in QGIS
I am working on QGIS. I have a raster of EVI, in which values are comprised between 0 and 1. I need to vectorize this raster in order to make an intersection with another vector.
My issue is that when ...
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0answers
62 views
Auto vectorization of raster in QGIS 3.14
Is it possible to do an auto digitize of a raster (downloaded and WMS)?
I would like to create vector polygons out of it.
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0answers
185 views
Thresholding distance raster and vectorizing in Google Earth Engine
I am struggling to convert a raster to a vector using Google Earth Engine.
I have produced an image using the ee.Image.distance() function where each pixel represents that pixel's distance in meters ...
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0answers
16 views
Distance between two vector lines in each east-west raster row (in QGIS)
I have 2m-resolution raster LiDAR data of a marsh edge from two moments in time and I am trying to calculate how much the marsh has "retreated" between the datasets.
I used the LiDAR data to ...
0
votes
1answer
26 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' : '', '...
3
votes
1answer
58 views
Removing additional lines from vectorized stream network
I have a large raster stream network (excerpt below) in QGIS that has been thinned using r.thin (light blue squares) and then vectorised using r.to.vect (pink lines). However, because some of the ...
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100 views
How can I vectorize contour lines from a DTM in QGIS?
I'm using QGIS 3.16. I am trying to do the following: Starting with a DTM model (geoTIFF format) I am computing the contour lines (100m) with QGIS. So far, so good. In order to import the results into ...
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0answers
47 views
QGIS does not polygonize [closed]
I have a .tif which I want to have polygonized. I take the Raster/Conversion/Raster to Polygon. QGIS 3.12 starts the process but never ends (once I waited half an hour). I maybe don't see a mistake.
...
1
vote
1answer
208 views
Creating a polygon from all raster values >0 in QGIS?
I have a raster layer with two values, 0 and 1. I want to create a polygon shape from all the 1 values.
I expected the "raster to vector" tool to achieve this, but this created another grid ...
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0answers
23 views
Raster Values into Gridded Polygons with Same Cell Size using ArcMap
I have data in the form of a raster with 1 km x 1 km cells. I need to transfer it into a vector polygon grid layer (USNG) which also has 1 km x km cells, but has divergence around UTM zones and does ...
1
vote
1answer
137 views
Using TIFF file in Intersect tool of ArcMap
I am attempting to do some geoprocessing with a CSV file and a TIFF file (trying to use the Intersect tool), but am experiencing some trouble with it. I can't seem to be able to input the TIFF file as ...
0
votes
0answers
24 views
FireCCI51 on Google Earth Engine: burnt area as shapefiles
How can I export my results as shapefiles (polygons) from the burnt area results (raster)?
I intend to export these shapefiles to ArcGIS for further anlysis on a specific national scale.
Link to ...
1
vote
1answer
166 views
Vectorize a raster TIFF based on its different class colors
I am using QGIS 3.16 and I have an int ratser tiff file, which shows classified land covers obtained from Sentinel-2. I need to create polygons over each class to classify and visualize each group in ...
0
votes
0answers
46 views
Creating shapefile of a raster image in QGIS 3.6
I use QGIS 3.6 on Windows and I have been trying to convert raster images into shapefiles. I managed to do that for Digital Terrain Models only, using the conversion --> vectorize tool in the qgis ...
1
vote
1answer
254 views
Converting Raster to Polygon in ArcMap
I've prepared my Shapefile in ArcMap 10.7.1 by Raster to Polygon. When I am opening this shapefile in ArcMap its showing a rectangular polygon around the shapefile like this:
When I select this ...
4
votes
0answers
52 views
Optimizing identification of tree stand boundaries
I am working on a workflow to identify tree stand boundaries. My desired result is the blue lines - I know it will never be like that, but I need it to be as good as possible. My best result is the ...
2
votes
2answers
1k views
Extract cells above certain values of raster file
I have a very large raster layer and with the values for noise emission. I'd like to extract all cells which are above a certain threshold value (e.g. 50 db) and convert them to an ESRI Shapefile so ...
5
votes
2answers
228 views
Identifying tree stand boundaries
I have a forest area, where I need to identify all the dividing lines between tree stands. I have a different amount of rastar files (RGB, NIR, DTM, DSM), and need an output with the boundaries as a ...
1
vote
0answers
30 views
Vectorizing a raster zone map without the lines turning into squares QGIS
Raster zone lines turn into squares after vectorizing my raster because of pixels between color zones QGIS
2
votes
0answers
48 views
Is my raster too large to realistically vectorize in ArcGIS Pro?
I'm new to ArcGIS Pro so go easy on me. I have a raster file(.img) of the continental US broken up into 30x30m grid resulting in about 10 billion individual pixels. I need to index each of these ...
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vote
0answers
256 views
ArcScan equivalent in QGIS
Is there any thing in QGIS which can perform operations like ArcScan? I put WMS polygon layer as a base map. I save it as PNG and when I add it as a raster layer, I can vectorize it with ArcScan. I ...
1
vote
1answer
85 views
Automatic Vectorisation in ArcGIS
Is there any method or tool/model for ArcGIS to draw automatic line based upon raster data values.
E.g i have a DEM and i want to automatically generate a line feature passing through all those pixels ...
0
votes
1answer
130 views
Error in overlay - formula not vectorized
I've run into another error while trying to get my predictive model to work. My base model is basically done (extracting locational parameters from archaeological sites in an area, and calculating a ...
2
votes
1answer
291 views
Split single band layer in QGIS
I have a single band raster layer, namely the USGS Global Mountain Explorer Home K3 dataset.
It is a 8 bit unsigned integer GeoTIFF of 200 Mb, with 4 grey values each corresponding to a mountain ...
0
votes
2answers
46 views
Two-value raster to generalized polygons (join pixels close together into one polygon) with short computation time in QGIS or ArcMap [closed]
I want to create application map for agriculture based on NDVI map. I have theoretical way how to do it.
My raster has two values (1 - red, 0 - green), the raster is quite big (100 hectares with 6 ...
2
votes
1answer
163 views
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. ...
1
vote
2answers
337 views
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 ...
1
vote
3answers
76 views
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,...
9
votes
1answer
613 views
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 ...
2
votes
0answers
180 views
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?
4
votes
0answers
101 views
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 ...
2
votes
0answers
35 views
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?
...
0
votes
1answer
84 views
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
...
1
vote
0answers
36 views
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 ...
3
votes
1answer
210 views
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 (...