The process of converting the coordinates of a map or an image from one system to another, typically by shifting, rotating, scaling, skewing, or projecting them.

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6
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1answer
207 views

Moving a shape around the earth while maintaining the proper projection

What is the transformation needed to be taken on every data point of a shape to rotate that shape around the globe. I'm trying to figure out the math behind this kind of transformation so I can ...
1
vote
1answer
52 views

Transformation accuracy or offset in ArcMap?

I'm trying to transform a map from UTM ED 50 zone 33N to WGS84 and vice versa in ArcMap 10.2.2. I'm doing this by using the Project tool in the Arc toolbox and choosing the ED_1950_TO_WGS_1984_12 ...
1
vote
1answer
57 views

QGIS georeferencer: Thin Plate Spline (TPS) residual

1) Is anyone able to explain in simple manner what does mean error exactly mean? I use metric values, so suppose 3.64109 is expression of meters and "e" is mathematical constant: ...
1
vote
1answer
47 views

Aligning data in GCS_North_American_1983 and GCS_North_American_1927 using ArcGIS for Desktop?

I have tried everything that I have found on this site so far and nothing has worked! I have used ArcGIS for 3 years but had never had to mess with coordinate systems as the 1st company I worked for ...
1
vote
1answer
57 views

Transform from WGS84 to Cylindrical Equal Area

What transformation should I use to go from GCS_WGS_1984 to Sphere_Cylindrical_Equal_Area? I am using Arc to project a dataset over for and area calculation and then will project it back.
1
vote
1answer
72 views

Geographic -> UTM Raster Rectification

I'm trying to use an image overlay in KML / Google Earth as the basis for adding extra info and returning this to Google Earth. In my utility app I can specify a rectangle to give me the ...
1
vote
1answer
104 views

Can I define a transformation between 2D and 3D in Geotools?

I'm using Geotools, and I need to convert coordinates between 2D and 3D coordinate reference systems. I recognize that there's no universally-correct way to do this: 2D -> 3D means "making up" a Z ...
1
vote
1answer
94 views

PostGIS transform geometry with long crs

How do i transform a geometry to a new geometry with a crs like urn:ogc:def:crs:EPSG::25832 st_transform(geom,integer srid) obviously doesn't work since my srid is a string found a solution ...
3
votes
0answers
51 views

Why different transformation behaviour ArcGIS Pro 2D/3D layers?

I am working with ArcGIS Pro and have noticed a strange difference between the co-ordinate transformation of 2D and 3D layers. Here are my transformation settings: I have the same layer ...
3
votes
0answers
242 views

Can GDAL Perform Vertical Transformations?

Can GDAL perform vertical transformations? If the answer is yes, please indicate which amongst these listed pages can explain how exactly to accomplish vertical transformations? If there is some ...
2
votes
0answers
51 views

Geoserver : create a rasterized polygon / dynamic fill for polygons with features from database

I decided to post here because I couldn't find any answer to my problems on the internet. So I am using geoserver 2.7-SNAPSHOT, everything is working fine but I need to implement a new function or ...
2
votes
0answers
93 views

Using ST_Affine() and trans_param() functions on vector layer

After reading this post How to georeference a vector layer with control points? I decided to give it a try to move/rotation/scale a polygon using Postgis. I have two polygons, polygon_from and ...
2
votes
0answers
129 views

How to locate a house on the 3D Map correctly?

I've done my 3D map generation in WebGL/THREE.JS project and have an issue with the building locations. I have the data about building position ( its polygon ) from DB server, but first of all I want ...
2
votes
0answers
62 views

How do you compute vertical transformations in QGIS?

How do you compute vertical transformations in QGIS? Ideally, the procedure / plugin will allow the loading of sundry geoid models.
2
votes
0answers
845 views

Projecting point in Leaflet from EPSG 900913 (same as 3857) to EPSG 2232 with proj4js returning unexpected results

I have a leaflet map from which I want to be able to query an api that accepts x y values in EPSG 2232 as inputs. Leaflet doesn't handle point transformations like Open Layers does so I am trying to ...
2
votes
0answers
209 views

What's the difference between CRS 4326, CRS 4978, and CRS 4979?

CRS 4326, 4978, and 4979 are all based on WGS84. 4326 is called "geographic 2D" 4978 is called "geocentric" 4979 is called "geographic 3D" What are the differences between these three? And why ...
2
votes
0answers
197 views

projection discrepancy with gdal (1.9) and proj4

I boiled the problem down to that python example: import sys try: from osgeo import gdal from osgeo import osr except: import gdal import osr if __name__ == '__main__': version_num = ...
2
votes
0answers
199 views

How to decode Magellan URL coordinates to lat/lon

Magellan uses this URL to designate a coordinate in New York: mgn:///address/?coord=merwFvlqbM,name=Viva%20Herbals%20Pizzeria,number=179,street=2nd%20Avenue,city=New%20York,country=US How can I ...
2
votes
0answers
614 views

Use MS SQL Server to convert MGRS to Lat Long

Below is the SQL for converting Military Grid Reference System (MGRS) to decimal Latitude and Longitude. It is very accurate, but not perfect. If you can make it work 100%, it is yours, but PLEASE ...
2
votes
0answers
453 views

How to transform Lambert to WGS84 in SQL Server?

Need to create a SQL view of calculated Lat/Lon values from an existing SQL view of County Coords. Loaded up SQL Server Spatial Tools and registerd CLR types. Lambert generated a resource error. -- ...
1
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0answers
59 views

How does OpenLayers 3 handle coordinates?

Ol3 always uses the flatCoordinates because obviously it needs 2d-coordinates as the screen is only 2-dimensional. But how does OL3 calculate the flat representation? For example if my view’s ...
1
vote
0answers
48 views

Why does the transformation bring bad results?

I have this map which has a polygon drawn on it. For the background map I use a WMS via ol.source.TileWMS and the polygon uses a ol.source.Vector object. Normally my view projection is EPSG:31467 but ...
1
vote
0answers
35 views

How do I compute uncertainties in the positions transformed using Helmert transformation?

I am familiar with Python, MATLAB and Mathematica. My data is given by Cartesian coordinates (positions in X,Y,Z (meters), standard deviations XX, YY, ZZ (meters) and a correlation matrix (XY, YZ, ...
1
vote
0answers
29 views

Transforming Data using 2D Costum Transformation in Arcmap 10.2 for Desktop

I have ArcMap layers of roads, buildings etc. in one reference system (Israel_TM). I need to transfrom all this data (while keeping the topology) to pixel-space "reference system". I have already ...
1
vote
0answers
75 views

Clustering the WGS84 point features (projection transformation aspects)

My question is quite trivial and was discussed many times before (like here) but in our case it has the confounding extra requirements... The list of sparsely distributed 2d point features is stored ...
1
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0answers
71 views

How use DataFrame Geographic Transformation User Interface with ArcObjects?

I am bringing data from SQL Server into ArcMap with ArcObjects as a Query Layer. If I do this manually, a 'Geographic Coordinate System Transformations' UI pops up. I would like the same thing to ...
1
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0answers
61 views

Node.js transformation from NAD83 to WGS84

I've used the excellent npm shapefile library to import Canadian electoral districts into MongoDB. Here's a sample file: http://ftp2.cits.rncan.gc.ca/pub/geott/electoral/2011/fed308.2011.zip Is ...
1
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0answers
72 views

Geodjango transform introduces large errors

Apologies for the possibly naive question. I'm trying to understand how Geodjango (running on PostGIS) deals with coordinate transformations, and am experiencing some unusual behaviour. Let's say I ...
1
vote
0answers
62 views

Transformation of OGR style data

I have been using GDAL/OGR in a project and it is going quite well. I have been re-projecting data from various source formats into a single CRS (using the C# bindings), but one issue I have come ...
1
vote
0answers
194 views

Geokettle transformation for FileGDB to SHP

I want to transform FileGDB layer to Shapefile on Geokettle. Firstly i added OGR Input and than i added a Shapefile Output. And i entered parameters shown on the screenshot but i got errors for ...
1
vote
0answers
63 views

How to identify grid shift file used by osgeo in Python?

I wrote a Python script reprojecting points from a source coordinate reference system (SCRS) to a target one (TCRS) both identified by an EPSG code. I would like my python script to retrieve details ...
1
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0answers
766 views

ArcPy 10.1 PointGeometry.projectAs()

I'm trying to reproject an X,Y passed in from an Add-in. So far this works fine: pointGeometry = arcpy.PointGeometry(arcpy.Point(x,y),srIn,False, False) projectedPoint = ...
1
vote
0answers
198 views

On the usage of Proj4Js->tmerc.js

I am using "proj4js & open layers" for my mapping. I got projection & datum (which is based on "Transverse Mercator") of a local plane and this plane is part of a grid which returns ...
1
vote
0answers
167 views

Can I overlay layers in Dealul Piscului 1970 and WGS84 in QGIS?

I have a 10 Gb ECW file (mosaic of a whole county) that is in Oblique Stereographic projection with Datum: Dealul Piscului 1970. The problem was that no matter the Default CRS for new project was, ...
0
votes
0answers
13 views

GDAL raster shifting with python error: 'NoneType' object has no attribute 'GetGeoTransform'

I'm trying to shift a georeferenced raster by 0.5m N and 0.5m W in QGIS using the python console: from osgeo import gdal # Open in read/write mode rast_src = gdal.Open('test_raster.tif', 1) # Get ...
0
votes
0answers
24 views

Is it possible to put a raster layer on a shifted Chinese basemap using leaflet API?

Recently, we want to develop an application with leafleat and gaode basemap because some features of these products fullfill our basic needs. We want to overlay some raster layers caculated by spatial ...
0
votes
0answers
26 views

Linear units do not correspond after georeferencing map?

In ArcGIS 10.1, I georeferenced an archaeological settlement plan. The georeferecing was made identifying Ground Control Points on the online aerial imagery provided by ArcGIS itself. 4 GCP were used ...
0
votes
0answers
34 views

Satellite Image of same projection system , do not overlap

I have two satellite imagery with same projection system i.e. QND_1995_Qatara_National_Grid as Spatial Reference and D_QND_1995 as Datum. Satellite Image A) Received in WGS84 and converted it to ...
0
votes
0answers
7 views

Error in using gdal java binding

I am using the java binding of gdal to project a set of coordinate points from UTM to lat/log using the CoordinateTransformation Class of gdal. I have written the code as follows: ...
0
votes
0answers
18 views

Precise aligning of two web layer

In Arcmap I add basemap from arcgis server (arcgisonline.com). On top of it I add another layer from a regional arcgis server which is in Bessel 1841 coordinate system. In this case Arcmap shows ...
0
votes
0answers
30 views

How to overwrite/change attribute values with QspatiaLite in qgis 2.6

I tried to work on the "tbl_datum_transform" table which is included srs.db data file. Just to let you know... i try to fill in the ntv2 - BETA2007 grid. How can i fill in something in the ...
0
votes
0answers
32 views

How to Transform Many Projections Into One With SQL Server

I know very little SQL Server, but am quite familiar with Arc and Python. The data I want to transform is point data which is in a single table [ID], [X] [Y], [COORDSYS]. There are 5 possible ...
0
votes
0answers
34 views

Auto-reprojecting (st_transform) SRIDs in Postgis

I have a postgis table that is edited from different sources. The points added from Source 1 are in SRID 23030. The points added from Soruce 2 are in SRID 4230. I want all the points in the table ...
0
votes
0answers
57 views

Four parameter Helmert transformation using four points

I'm looking for an algorithm to calculate a Helmert transformation using four reference points. Plus, does anyone know how I can calculate the error once I've completed the transformation?
0
votes
0answers
58 views

Precision loss when transforming coordinates systems in GDAL (vector layers)

Anybody knows the order of magnitude of the error introduced when transforming coordinates using GDAL? More specifically, I would like to know if significant error is introduced when the ...
0
votes
0answers
28 views

Creating hierarchy of Feature Elements in MapForce

I use FME to translate SQLServer tables into gml document. In FME, I make one-one connections (every feature type produces new feature type in output). This document is not 'structured' as I want. ...
0
votes
0answers
84 views

Offset WGS84 linestring based on pixel values

I would like to split up some roads based on their driving direction. For this, I need to offset the roads 2 pixels to the right, in the direction of the linestring. I have the coordinates in WGS84 ...
0
votes
0answers
23 views

OpenLayers transform control box properties

I'm using OpenLayers for my GIS application. My problem is that when I add a transform control to a polygon feature, it looks very "messed up". The box for the transform control is completely ...
0
votes
0answers
35 views

QGIS layer only displays when I uncheck on-the-fly transformation

I have a layer that covers the stats of Indiana that has the following Layer SRS: +proj=utm +zone=16 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs It will not display unless I uncheck the ...
0
votes
0answers
110 views

Transforming WFS Projection

I am trying to overlay features from a WFS using OpenLayers, my geometries in database are in EPSG:27700 and my map's projection is EPSG:3857. My mapfile returns data in EPSG:27700. Is there any way ...