Questions tagged [transform]
The transform tag has no usage guidance.
14
questions with no upvoted or accepted answers
4
votes
0
answers
72
views
How to reduce the clothesline-effect in ST_Transform?
When we use standard ST_Transform (e.g. PostGIS implementation), from a SRID to another that curves straight lines, the original straight lines represented by two points, that must be transformed into ...
- 2,292
3
votes
1
answer
337
views
Wrong transformation between British National Grid and WGS84
I have access to a remote DB with the following specifications:
PostgreSQL 11.12
POSTGIS="2.5.2 r17328" [EXTENSION] PGSQL="110" GEOS="3.7.0-CAPI-1.11.0 673b9939" PROJ=&...
- 309
2
votes
0
answers
67
views
Transform coordinates from ITRF2014 (2020.39) to ITRF2008 (2010.0) using PROJ4?
Due to the fact that I cannot convert the coordinates obtained at epoch 2023.39, X = 1710698.054 meters; Y = 3046082.270 meters; Z = 5318707.282 meters, I still cannot understand how to use in this ...
- 21
1
vote
0
answers
44
views
Change layer CRS without displacing relative locations with regard to old CRS
I have some points with projected CRS EPSG 3003 (Italy) and I'm displaying them in QGIS on a project map with CRS 3003. If I export the same points with projected CRS EPSG 7791 (Italy) and load them ...
- 887
1
vote
0
answers
29
views
QGIS Australia GDA94 to 2020 Transformation File (NTv2_3>
I'm looking to convert some Australian GIS data from GDA 94 to 2020. The reprojection exists, but I need to use a particular transformation - specially NT v2_3 Conformal (this exists in ESRI). I ...
- 11
1
vote
1
answer
632
views
Converting between WGS84, SK42 and ED50 geodetic reference datums
I need to convert between WGS84, SK42, and ED50 geodetic reference datums in either a UTM or MGRS coordinate system given GPS coordinates I've been using pyproj for the conversion by finding the EPSG ...
1
vote
0
answers
114
views
Visualize transformation when reprojecting from Mercator to equirectangular
I am trying to visualize the map distortion that occurs when reprojecting from Mercator to equirectangular coordinate systems. The actual reprojection is not difficult, but I want to save images (...
- 11
0
votes
0
answers
52
views
User defined transformation in QGIS
Is it possible to define custom transformations within QGIS, such as for user-defined CRSs? If this cannot be accomplished directly through the graphical user interface, might there be an alternate ...
- 1
0
votes
1
answer
347
views
Read GeoJSON object in a CSV file column and transform it to geometry
I have a column ('geo_shape') that contains GeoJSON object type of linestring geometry and, so far, I didn't manage to read and transform it to a GeoPandas/shapefile type of geometry.
Here is a way ...
- 1
0
votes
0
answers
147
views
I am trying to convert 3D world coordinate to a 2D image coordinate in the form of pixels
I have a GeoTIFF file. I am trying to convert 3D world coordinate to a 2D image coordinate in the form of pixels. How can I do that?
Suppose, I can extract latitude, longitude and elevation data from ...
0
votes
0
answers
147
views
st_transform does not work
I am trying to transform a geometry from srid 4326 to 26915.
SELECT
ST_Transform(s.geompos, 26915)
FROM sites s
But i got error :
ERROR: could not form projection (LWPROJ) from 'srid=4326' to 'srid=...
0
votes
1
answer
104
views
Enlarging gBuffer width changes polygon shape
I am having some issues with spTransform and the gBuffer function. I basically have a polygon that I want to buffer with gBuffer (not with st_buffer for other reasons). For some reason the shapefiles ...
- 9
0
votes
0
answers
749
views
Transform coordinates length to pixel length?
Is there a function to transform a coordinates length to a pixel length?
I need this function for cropping and scaling map images to be inserted as layers in an OpenLayers Map.
The map images are ...
- 81
0
votes
1
answer
238
views
GeoTools: Geo Transform incorrect
I am transforming a coordinate between Lambert Conformal and WGS84. The values returned by GeoTools do not seem correct.
From:
PROJCS["unnamed",
GEOGCS["Coordinate System imported ...
