Questions tagged [proj]
A library for performing conversions between cartographic projections.
399
questions
1
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0answers
13 views
Proj4 string missing datum information for SAGA outputs loaded into R
I've produced a set of topographic derivatives using both SAGA and ArcGIS. They are all in the same CRS.
When I load them into R, however, the proj4 strings are different:
>arcRaster
class ...
2
votes
1answer
27 views
What is the link between proj4js and proj
Question
I am simply wondering, what is the relationship between the web oriented proj4js and the PROJ C++ well known library (on which for example GDAL/OGR relies)?
Is there any link between these ...
2
votes
0answers
40 views
Did the syntax for proj4 change with QGIS 3.10?
In QGIS 2.8 I was able to successfully do a transformation using the following proj4 syntax :
+proj=utm +zone=18 +ellps=clrk66 +datum=WGS84 +towgs84=-11.0584,163.8703,190.541,0,0,0,0 +units=m +...
1
vote
0answers
31 views
Generate custom WKT Coordinate System definition from local / WGS84 pairs of coordinates [closed]
I am wondering if it possible to create a custom WKT for coordinate transformations based on pairs of WGS84 lat/lon and the corresponding local N/E values. So like a minimum 2 pairs?
If so is it ...
1
vote
1answer
19 views
Is there a proj4 string for GDA2020 (epsg:7844) that we use to transform from 3857 or 4326 to gda2020 using dot spatial .net library
We are using dot spatial library for transformation from one projection to other. We are planning to include the new release GDA 2020 projections. Is it as simple as just adding the proj string for ...
8
votes
2answers
150 views
Setting proj parameters of old map
I would like to georeference these fantastic old public domains maps
https://legacy.lib.utexas.edu/maps/ams/italy_50k/
I started from this one, and it has these projection parameters.
Then I have ...
2
votes
1answer
49 views
How can I determine if a transformation between two CRS is simply scaling/translating or more complex?
We are using pyproj to transform between coordinate reference systems. What is a good way to check if the transformation is simply scale/translate/units? Basically, I want to know if a grid in the ...
1
vote
1answer
18 views
GDAL Convert Format with PROJ string
I would like to perform the following transformation in the GDAL Convert Format tool in QGIS:
projinfo -s ETRF2000 -t ITRF2008 -o PROJ Candidate operations found: 1 --------------------------...
1
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0answers
35 views
Creating custom PROJ projection from control points
I have a JPG raster, and I used QGis to georeference it with "control points", which are pixel coordinates linked to map coordinates, in EPSG:4326 (lon, lat).
Here is an example of the control points ...
2
votes
0answers
48 views
OpenLayer's graticule doesn't properly work
I am making a map of Krasnoyarskiy krai subject of Russia. I have defined a custom projection that should be used for this area using proj4 string. I need to show lat/long grid only for this territory....
0
votes
1answer
54 views
Create prj4 file for NAD27 Mexico from prj file for import to QGIS
I would like to be able to add the NAD27 MEXICO projection to QGIS, MapInfo, etc. Global Mapper has this projection, and the prj file is:
PROJCS["NAD_1927_UTM_Zone_13N",GEOGCS["...
2
votes
1answer
51 views
GDAL Python - How I can determine the PROJ version used
As PROJ recent major update introduces importants change in the API, I need in my script to check what is the PROJ version compiled with the current GDAL installation of the user. I know I can get the ...
4
votes
0answers
61 views
GIS proj pipeline
I would like to create a custom projection in QGIS 3.10.
It is a local stereo and the reprojection between WGS84 and the local stereo uses proj pipeline. For example in cs2cs it is (which works well):
...
6
votes
1answer
116 views
How can I convert the Gaussian coordinates( Gauß-Krüger) to the WGS84 coordinates
I have a list of WGS84 and Gauss coordinates, but how to convert another WGS84 coordinates.
I want to use PROJ for conversion.
What is PROJ string like?
| Name | x | y | H | ...
1
vote
1answer
36 views
Creating custom proj4 string from components
I'm trying to work with NOAA's NDFD weather data, which are released as rasters in GRIB format. Specifically, I'm currently trying to get the pixels that intersect an arbitrary geometry.
Information ...
1
vote
1answer
41 views
Custom PROJ CRS for shifted, rotated, and skewed axes?
It is possible to create a custom PROJ definition for a cartesian CRS with shifted, rotated, and skewed axes? For example:
Where The x-axis is formed by the line AC, the y-axis by the line AB, and ...
0
votes
1answer
55 views
What epoch does Proj4 for EPSG:4326 assume? NMEA stream provides Lat Lon at measurement epoch
I get a NMEA stream exported from Applanix PosPac in the epoch the measurements took place (2019). These coordinates go into a software, that interprets the NMEA Lat Lon as EPSG:4326 with Proj4 ...
1
vote
0answers
39 views
gdalinfo returns PROJCS[“unnamed”] but QGIS returns the correct projection
I'm trying to understand why my gdalinfo call to a specific file returns "unnamed" for the PROJCS node.
The call looks like this: ./gdalinfo /path/to/file/dem.tif.
Output (notice the "unnamed"):
...
1
vote
0answers
25 views
SR EPSG 3035 ETRS/LAEA Europa to EPSG: 6204 Macedonian State Coordinate System python
I would like change a raster dataset from EPSG: 3035 (ETRS89/LAEA Europa) to EPSG: 6204 (Macedonia State Coordinate System)
My WKT for the first coordinate system is:
PROJCS["ETRS89 / LAEA Europe",
...
2
votes
0answers
28 views
Why QGIS cannot georeference a Grib2 file with CRS (PROJ.4 and OGC WKT2)?
Situation:
I have some .grib2 files that I downloaded from a (supposed to be) reliable source. When I do
$ gdalsrsinfo file.grib2
I get:
PROJ.4 : +proj=lcc +lat_0=38.5 +lon_0=262.5 +lat_1=38.5 +...
2
votes
0answers
60 views
QGIS proj4 definition is not valid
In QGIS 3.4 I'm trying to add a custom projection that was used for topographic maps of Suriname in the 1950s. I have the parameters from an article about historical CRS used in the country. Using the ...
1
vote
1answer
31 views
Swift library to convert latitudes and longitudes from EPSG:4326 into EPSG:3857
I would like to know a Swift library or method that I can use to convert from 4326 to 3857. I have referred some libraries such as Proj4Swift and Proj.4, but to no avail. The first link does not has a ...
1
vote
2answers
72 views
Proj4 definition for WGS84 coordinates multiplied by 1000000
For some reason, a vendor found it convenient to move from a Gauss–Krüger coordinate system (EPSG:31466) to something like WGS84 but then multiplied by one million. Hence lon = 6090805, lat = 50777584,...
2
votes
1answer
97 views
QGIS/proj errors with EPSG:2951
I've built various QGIS projects that use Canadian UTM and MTM CRS. They worked just fine in QGIS versions through 3.8 (based on proj4 and ?proj5).
In QGIS windows version 3.10.0-3, things got borked ...
0
votes
0answers
21 views
How To parse one UTM location with a zone into another UTM location with another zone?
I'm working on an iOS app where the user can input 2 UTM locations, but the user is inputting 2 UTM locations with different UTM zones and I need to project one of them into another zone.
I tried to ...
2
votes
0answers
21 views
Project point from one UTM zone to other
I am currently working on a project where we have to figure out the position of one point based on the known position of two (user-input) points.
Now the problem is that the users could provide two ...
0
votes
0answers
24 views
Reprojection of Landsat 8 using the existing shapefile in ArcGis
I have downloaded a landsat8 and when I overlay it with a shapefile of the location where I want to extract by mask , the combination of landsat 8 and the shapefile are not matching. The shapefile is ...
1
vote
1answer
135 views
MapProxy Installation problem with PyProj
I'm testing MapProxy (1.12.0) on a Windows Machine and followed each step from the "Installation on Windows" docs.
I have a running virtualenv, used pip to install MapProxy and PyProj.
The command ...
0
votes
0answers
15 views
Bundling GDAL 3.0.2 with PyInstaller
I'm not sure if this is the right Stack to ask in, but I've been recently trying to bundle the latest wheel of GDAL 3.0.2 x64 downloaded from
https://www.lfd.uci.edu/~gohlke/pythonlibs/#gdal
for ...
0
votes
1answer
50 views
Get type of projection from pyproj CRS object
I'm used to using PROJ strings/dictionaries in python where I have access to a proj_dict['proj'] element. I have some calculations that I can only do with the PROJ.4 geos projection and otherwise ...
3
votes
1answer
38 views
Different results from cs2cs and gdaltransform
I expected to get the same result when performing a transformation using cs2cs and gdaltransform. However, the results differ:
echo "53.70015N 9.12875E" | cs2cs EPSG:4326 EPSG:3857
1016207.80 ...
1
vote
1answer
42 views
*.h5 Projection Parameters
I have a file named 'VNP13A1...h5' and I'm trying to georeference it in Python 3. I know how to read and extract data from this file and what I'm trying to do is automating this process for other ...
4
votes
1answer
122 views
To project, or not to project? Extracting raster values with R
I have a raster from which I need to extract values at point locations using raster::extract(raster_stack, points_sf).
The raster is at 30 arc-second resolution and came from WorldClim with ...
2
votes
1answer
53 views
Flipping coordinates in projection results in distortion. A simple mistake
Edit: I made an embarrassing rookie mistake late at night (excuses, excuses) and flipped my lats and longs. As a result, people searching for an answer to my original question will not be helped by ...
2
votes
1answer
80 views
Display ESRI MapService (WMTS) with EPSG:28992 coordinate system in OpenLayers web map with OpenStreetMap base layer
ESRI MapService https://tiles.arcgis.com/tiles/nSZVuSZjHpEZZbRo/arcgis/rest/services/Historische_tijdreis_1870/MapServer have EPSG:28992 coordinate system. In QGIS I can add this layer via WMTS https:/...
1
vote
1answer
40 views
Incorrect false northing in pyproj?
I am using version Rel. 5.2.0, September 15th, 2018 on OSX but get the same answers on other platforms with other versions.
prompt> echo 3 0 | proj +proj=utm +zone=1 +ellips=wgs84
500000.00 ...
3
votes
1answer
74 views
Geos projection not centered on the equator?
I'm working with QGIS and satellite view projections, in order to achieve something similar to the maps created by Richard Edes Harrison for Fortune magazine in the '40s (reference). I have a question ...
3
votes
2answers
183 views
Generating a custom flat projection in pyproj
I have little experience with pyproj, but I want to achieve the following task:
I have a trajectory of a robot, given in lat/long coordinates which I want to convert to x/y Coordinates. And I want to ...
2
votes
0answers
22 views
How to run OSGeo4W shell for molodensky transform?
I'm a beginner with Proj, so I just downloaded proj, and I'm using the OSGeo4W Shell and when I try to run the example
proj=molodensky a=6378160 rf=298.25 da=-23 df=-8.120449e-8 dx=-134 dy=-48 dz=...
0
votes
0answers
29 views
Custom metric projection definition in QGIS with reference point and azimuth [duplicate]
I need to create a custom CRS.
I have a reference point in UTM NAD83 18N, an azimuth (30) and the extent. The projection must be metric, I know I have to use PROJ4 but the language is not very ...
5
votes
3answers
197 views
Making a GeoTIFF using Google Earth Data
I'm trying to make a GeoTIFF using geotifcp, which I'll then upload to GeoServer.
I've got an image overlay (part of a .kml) in Google Earth, so I tried to use its bounding box to create a world file,...
3
votes
1answer
102 views
CRS validity and PROJ versions
I'm not sure where the right place to raise this is, so:
The PROJ strings for EPSG codes 4151 and 4283 are identical:
+proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs
which is a hassle ...
3
votes
1answer
259 views
How to use a specific transformation for a coordinate projection with Python
I try to use Python to project single coordinates from Gauß-Krueger-coordinate system (EPSG:31467) to ETRS89-UTM (EPSG:25832).
I'm using the way Antonio Falciano showed here.
So my script looks like ...
6
votes
1answer
205 views
Explaining pyproj to_epsg min_confidence parameter?
Following on from this question How can I get epsg code in pyproj with version==2.1.3, I discovered that sometimes when intialising a pyproj Proj instance with a string ESPG code eventually results in ...
2
votes
1answer
804 views
How to create a grid of pixel coordinates from the corners of a MODIS tile?
I have an HDF4 file whose StructMetadata.0 contains the following attributes:
UpperLeftPointMtrs = (-20015109.354000,1111950.519667)
LowerRightMtrs = (-18903158.834333,0.000000)
These are X and ...
-3
votes
1answer
43 views
Proj4 give always a false answer [closed]
I'm trying to use Proj4 (dll) to convert from Lambert93 to WGS84 but it always give a wrong answer:
// EPSG:2154 : Lambert 93 definition: https://spatialreference.org/ref/epsg/2154/proj4/
const char*...
1
vote
0answers
75 views
Applying 3D-Helmert Transformation Parameters in QGIS?
I have received a set of local transformation parameters from my surveyor to go from WGS84/UTM36S to ARC1950/UTM36S (See picture below)
The way QGIS does the transformation is not the best. I am ...
0
votes
0answers
21 views
NDFD Grib2 geotransform
I am trying to transform the projection for my data in grib2 format to long/lat, but I'm not sure I'm using the correct EPSG. The data says it uses a "Lambert_Conformal" projection with a WGS84 ...
2
votes
0answers
111 views
WGS84 to local coordinate system [closed]
I have a point cloud and would like to move this to the local coordinate system for example from Revit facing toward the first quadrant. We have a file with 3 ground reference points and on-site ...
0
votes
1answer
57 views
proj: Oblique Mercator specifying two points on central line
I'm trying to use Oblique Mercator in QGIS 3.4, which uses proj to calculate coordinates conversion. I specify two points in the central line, rather than specifying the center and alpha.
Oblique ...
