Questions tagged [vectorization]

The conversion of raster data (an array of cell values) to vector data (a series of points, lines, and polygons).

Filter by
Sorted by
Tagged with
0 votes
1 answer
30 views

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 ...
0 votes
1 answer
81 views

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 ...
1 vote
1 answer
96 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 ...
7 votes
3 answers
164 views

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 ...
1 vote
1 answer
58 views

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 (red in the figure below) ...
0 votes
0 answers
18 views

Vectorize and export table in GEE

I have a classified image obtained from RF algorithm in GEE. I want to extract and export each class separately to drive. First as an image by this script (for example for class water of ...
1 vote
1 answer
26 views

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 ...
1 vote
1 answer
119 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 ...
6 votes
0 answers
116 views

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:...
5 votes
1 answer
2k views

Convert image in KMZ to polygon

I have a KMZ file that contains several image overlays (RF coverage plots). I would like to convert the image overlays to polygons to decrease loading time in Google Maps. Currently I'm tracing a ...
0 votes
0 answers
54 views

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 ...
7 votes
1 answer
162 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
1 answer
2k views

Converting raster to line vector layer

I would like to convert all values having the value 1 in a binary raster to a line vector layer. The following image shows the binary raster (1=white and 0=black): The optimal output would look like ...
5 votes
2 answers
90 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 ...
2 votes
1 answer
223 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. ...
0 votes
1 answer
89 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
0 answers
51 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 ...
0 votes
0 answers
40 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
1 answer
247 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 ...
1 vote
0 answers
44 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 ...
1 vote
3 answers
90 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,...
2 votes
1 answer
34 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 ...
2 votes
1 answer
2k views

Converting large raster to vector?

I have a shapefile which contains 10.000 polygons and I want to know how many of them falls on a specific land use. Unfortunately, the land use map that I have to use is a raster map and not a vector ...
2 votes
0 answers
264 views

R raster rasterToPolygon Error

I'm trying to convert a RasterBrick to polygon, across four different resolutions. It works for the coarsest three resolutions, but for the finest resolution, I get an error that I can't find much ...
28 votes
5 answers
33k views

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 ...
1 vote
0 answers
36 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, ...
0 votes
0 answers
75 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 ...
0 votes
0 answers
50 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 ...
9 votes
3 answers
11k views

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 ...
0 votes
1 answer
46 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 ...
0 votes
0 answers
32 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,...
0 votes
0 answers
62 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
2 answers
332 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 ...
0 votes
1 answer
143 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 ...
1 vote
0 answers
18 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
1 answer
34 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
1 answer
679 views

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 ...
0 votes
1 answer
3k views

How to polygonise a binary raster with python?

I already asked this in StackOverflow, but maybe it's better here. I have a ndvi raster that I binarized (I put my threshold at 0.35) with a script python and I wanted to polygonize this raster, in ...
0 votes
0 answers
153 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 ...
24 votes
5 answers
25k views

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 ...
1 vote
0 answers
59 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
1 answer
428 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 ...
0 votes
0 answers
28 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
1 answer
255 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 ...
14 votes
2 answers
6k views

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 ...
0 votes
0 answers
29 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
1 answer
282 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
1 answer
870 views

Raster to polygon fails in ModelBuilder iteration

I need to vectorize some rasters to polygons and to do so, I use the "Raster to Polygon" tool in ArcGIS Desktop 10.4. As there are many rasters, I use a iteration in ModelBuilder. The output ...
0 votes
0 answers
67 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
1 answer
362 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 ...