Questions tagged [distortion]
The distortion tag has no usage guidance.
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Align set of satellite images
I have a problem my set of four satellite images (4 different years of observations) of the same area are not aligned and more than that I see that there is a distortion problem also.
I found this ...
CommunityBot
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CRS selection for global product with minimal area distortion
I am building a model that takes data from different sites around the world as input where each pixel has a 10m resolution. I am now seeking a CRS system that works best for my use case. The ...
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Distorted h3 hexagons using h3js with Mapbox
When a user clicks on a Mapbox streets-v11 map, I'm attempting to:
Take the clicked point, and identify the h3 hexagon (at resolution 10) around the point
Convert the hexagon coordinates into the ...
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Add projection warp calculation to preserve correct scale when exporting map for printing
I'm working on my own widget for printing large maps based on the ArcGIS printing service. The main feature of the service will be dividing the large area to separate parts in specified paper format.
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Check geometries distorting polygons when removing gaps
Using QGIS 3.10.9 with the check geometries plugin (v0.1), and I have a simple polygon layer as a test run with a deliberate gap.
I use the check geometries plugin with the topology check 'check for ...
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Export distortion grid and displacement vectors from MapAnalyst and use them in QGIS: incorrect projection
I use MapAnalyst, a FOSS tool for the accuracy analysis of old maps. The tool creates, between else, Distortion Grids and Displacement Vectors/Circles (see screenshot). These can be exported as ...
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Artefacts in Sentinel 1 Imagery
When loading Sentinel-1 imagery using the GEE template script and zooming to the Arabian Peninsular some areas appear distorted with higher values for VV and VH bands independent of the time frame ...
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Rotating a set of points with an angle with rotation matrix: why is result "distorted"
What might be going wrong with my rotation of set of points as result look distorted? I have a set of points (X,Y). I calculate the mean (= "center of gravity") of them and subtract it from ...
- 76.1k
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Evaluating map projection scale error
This is related to a previous question How to determine projection parameters when customizing a projection
I posted.
I am trying to quantitatively evaluate scale distortion associated with choosing ...
CommunityBot
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Shift country polygons to other world-regions in QGIS, adapting it's size corresponding to the true area
On the website The true size of ..., you can shift the shape of countries to other world regions to see the true size (area) on a distorted map (mercator projection). Dragging Greenland over Africa ...
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Keep the map straight with arcgis projections
I need to overlap DEM file with an historical map.
The historical map doesn't have georeferencing so I need to add some control points, but when I do this the map is distorted.
There is a way to ...
- 76.1k
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Converting coordinate system produces distorted image
I have a GeoTIFF file produced from a LAZ file. I would like to convert its coordinate system to the WGS84. However, after the conversion the resulting image is skewed (has a perspective distortion).
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Avoid area distortion when moving features
I'm a newbie to QGIS. I have a map (vector layer) of the American states + DC with the EPSG:2163 projection, and I want to move Alaska down to southwest of California, as in many political maps. How ...
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Leaflet activearea interferes with esri-lealet imagelayer
I am creating a leaflet application that uses various data sources / map layers. I found a great source for global ground cover from esri. It is an imageLayer. Using an esri-leaflet imageLayer, I ...
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ST_AsMVT vector tiles distort at low zoom levels
I'm serving up a data from PostGIS by converting it into a tile and then bytes and then onto a leaflet map. It all works, with one exception, the latitudes stretch ever greater towards the poles when ...
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Distorted H3 hexagons - even though projection is matching
Using H3-py's h3_to_geo_boundary a WKT linestring (via shapley polygons) can be generated.
When later visualizing the hexagons, why are they distorted? How can this be fixed?
To my best knowledge, ...
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What is the area of my shapes?
I created overlapping geometries and I would like to know the area of the intersection.
import geopandas as gpd
from shapely.geometry import Polygon
polys1 = gpd.GeoSeries([Polygon([(0,0), (0,1), (1,...
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How do I rectify a distorted aerial image in QGIS?
When I place an aerial image in QGIS 3.4.15 it becomes distorted (in the attached the left image is correct, the right image is distorted). How to I rectify this?
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Creating time-space map by distorting city-points polygons using QGIS?
I've already 3 main layers on shp in qgis: the points of some places, the cities polygons and a grid of 10km, as you can see on the image. I would like to distort the map using time values to modify ...
CommunityBot
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ArcMap QGIS different distortion
I have a problem with a shapefile (EPSG:31287 MGI_Austria_Lambert). I tried to solve it on my own, but I just have no clue as to what's the error.
So I use a basemap from basemap.at (WMTS: https://...
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QGIS distorted contour from DEM
The contour map that I generate from a Maps Made Easy (MME) DEM produces a distorted result and I’d like to learn how to correct the problem.
Shown is a pool that has been physically measured to be ...
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Fix distortions when reprojecting cshapes world maps?
I am using the cshapes package in R as a source of historically accurate country borders. While the default WGS 84 maps plot fine, I would like to reproject the maps. This introduces some distortions ...
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How can I project a raster DEM and not get serious distortion in the resulting DEM?
Please see this link to see a fine example of what I am dealing with.
Distortion in projected raster
My specific situation is that I have downloaded DEM data from the National Map (USA) and it comes ...
- 76.1k
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Distance in SRTM image vs. Google Earth/etc
I am producing DEMs and various maps for own book project; just learned to use GIS software for this project. I am using QGIS (2.14.21) and SRTM data (CRS:WGS84 EPSG:4326). I want square maps that ...
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Clipping vector layers with different CRS
I have two vector layers:
provinces (Belge_Lambert_1972, EPSG:103300) - clip layer
building (WGS 84/ Pseudo Mercator, EPSG:3857) - input layer
I would like to overlay them, however there is ...
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548
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Distorted image of KML in QGIS
I just started using QGIS and I used Google Earth to export images as KML ground overlays. I then bring the KML into QGIS, then georeference the raster. I tried using de CRS 6370. However, the image ...
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Resampling WGS84 to ETRS89 causes change in pixel dimension
I'm a first time QGis user and got some resolution troubles. I need to create a DEM for whole Europe using SRTM 1-arc second (30m) from USGS. As I need the slope algorithm in a later step, I have to ...
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True non-projected 3D grid world modeling
I did a search on this but I did not find anything much relevant yet. I was wondering how come there is no GIS software that would take a sufficiently accurate 3D surface model of the world (such as ...
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How to calculate zonal statistics of buffer zone with minimum distortion
I want to create 50km buffers around a large set of polylines that have a global extent. My objective is to calculate average raster values within each buffer zone.
The matter of confusion: I want ...
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After how much distance does the x,y coordinate system become noticeably distorted?
I'm working with maritime sensors that give information of moving objects it detects, in azimuth, range and elevation, and we convert it to x,y coordinates for our application to be able to process it....
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