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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2answers
51 views

How to set a coordinate transformation GRID

Does anyone know how to set a coordinate transformation in qgis so I can measure the distances in meters or kilometers? If anyone has a clue, would be just great. Thanks!
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2answers
81 views

Defining a scale number from the Helmert transformation

I know this is more bit of a cartographic issue, but maybe somebody would be able to help. I have an old map georeferenced to the openstreetmap with 50 identical points. I want to get the scale of the ...
5
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1answer
145 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 ...
2
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1answer
12 views

Distort image to display on leaflet.js based on known 16x16 point grid

I have an image that is a satellite picture, and with php gd I want to distort it so I can overlay it on a leaflet.js map. To make it a bit more simple, I have a grid of points, 16x16 which bind the ...
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1answer
51 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 ...
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1answer
160 views

Vector affine transformation in QGIS2

In QGIS 1.8, I can transform my point layer with the plugin "Affine transformation". So, this plugin don't exist in QGIS 2.0. Do you know a method to simply translate (i.e : X -> X+30000) in QGIS 2 ? ...
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1answer
46 views

QGIS batch affine transformations

I have multiple polygon and line shapefiles on which I would like to apply a translation so I was wondering if it is possible to batch process them (maybe with graphic modeler ?) or do I have to ...
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1answer
220 views

How to transform/convert Coordinate Reference System with Proj4 and php

Basically my question is: Can I combine the functions of proj4 with php in my server? For example, I would like to know if it is possible get data in WGS84 and transform in ETRS89. I need to get ...
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1answer
52 views

USGS FLT Hdr file interpretation

I have a legacy program that attempts to read USGS 1/3 arcsec data. When I compare results to GDAL, I find that the lat/lon to pixel conversion is off by 1 line. The reason (I think) is because the ...
3
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0answers
139 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
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0answers
59 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
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0answers
78 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
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0answers
48 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
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0answers
275 views

GDAL: Geotransform - rotated rasters (and ArcGis)

I am working on a GDAL driver for a proprietary grid-format. In some cases, the grids are rotated in order to get smaller file sizes. In my GDAL geotransform array, I do the following (showing a ...
2
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0answers
713 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
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0answers
128 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
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0answers
160 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
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0answers
179 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
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0answers
524 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
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0answers
394 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. -- ...
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0answers
31 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 ...
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0answers
38 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 ...
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0answers
112 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 ...
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0answers
55 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 ...
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0answers
419 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 = ...
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0answers
174 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 ...
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0answers
159 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, ...
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0answers
28 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
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0answers
31 views

WGS 84 Transformation issues with ArcGIS and Global Mapper

I have rasters, need to be geo-referenced in WGS 84 datum with Lat/Log (degree). I have geo-referenced using Global Mapper, which we usually used to use, because of its user friendly. Got a vector ...
0
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0answers
60 views

Is it possible to apply affine transformation (translation) to raster image?

Is it possible to move/translate a raster image in QGIS 2.2 (without using georeferencer) just like it can be done with a shapefile ? If not, alternatively can this be done with ArcGis?
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0answers
27 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 ...
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0answers
92 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 ...
0
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0answers
63 views

How to snap Vector Layer projection to Raster layer projection in QGIS?

I have raster in correct projection. I used ShapeFiles, and marked objects(manually), but i found out that my vector layers have different projection, so they have different size and position. Is ...