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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7
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1answer
2k views

Characteristics of different methods to convert ECEF to LLA

I'm trying to convert ECEF (Earth Centered, Earth Fixed) coordinates, which are defined in X,Y,Z, centered at (0,0,0) to LLA (Latitude, Longitude, Altitude). There are a couple of methods I found on ...
5
votes
1answer
2k views

Mercator projection: problem with latitude formula

I'm trying to get the position of a coordinate on this map (source Wikipedia): If I'm correct than the formula for the position of the latitude would be: R * ln(tan(pi/4 + latitude / 2)) But ...
4
votes
1answer
3k views

Transforming geometry coordinates from SRID 4326 to SRID 3011

In SQLServer geometry field, I want to change the coordinates of geometry from one spatial reference system to another spatial reference system (from SRID 4326 to SRID 3011) by using ST_Transform. But ...
2
votes
1answer
2k views

Projecting shapefile with transformation using OGR in python

I want to change coordinate system of a shapefile from British National Grid to WGS84 (in order to be able to convert it to KML later on). To get the best results of projecting I would like to use ...
3
votes
1answer
372 views

How do I perform one-step transformation in python?

I would like to perform transformation for this example data set. I have here four pairs of adjustment points and want to transform given point coordinates from primary system to secondary system ...
3
votes
2answers
1k views

How to reproject from Michigan Georef to WGS84 in QGIS?

I am trying to reproject a michigan state land shapefile which is the NAD83/ Michigan Oblique Mercator EPSG:3078 to the WPG84 EPSG:4326 projection. However when i try to do this my map gets squished ...
2
votes
2answers
894 views

How to convert from GeoTIFF to PNG/JPG and Web Mercator in Java?

I'd like to convert raster image from (geo)tiff to an png/jpg and afterwards if it is necessary ... I'd like to convert the coordinates with help of EPSG-Codes to the OSM/Google Projection(EPSG: ...
2
votes
4answers
1k views

How can I transform some KML data to Sql Server 2008 using FME?

I've just downloaded FME 14 day trial. I'm trying to see how easy/hard it is to transform some KML data (a simple neighbourhood shape) into my Sql Server 2008 database using FME. I sorta don't even ...
2
votes
2answers
234 views

How to perform multiple string transformations using one transformer in FME Workbench?

I am converting a .DWG file to .GDB. All fields in DWG file are of Char type. The target .GDB needs to have some attributes in Float data type. For now, I am using one StringFormatter transformer for ...
2
votes
0answers
391 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
158 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, ...
1
vote
1answer
223 views

Dynamic defining of transformation type for ISpatialReferenceFactory.CreateGeoTransformation call

Suppose given a point (IPoint) in some coordinate system. Required to transform it to another coordinate system. If both of coordinate systems are predefined, we can use IGeometry2.ProjectEx with ...
2
votes
3answers
126 views

What Danish position format is this?

I have been given a list of locations within Denmark. Most of the are in decimal degrees. However, some of the positions are in different formats and I can't figure them out. Does anyone recognize ...
3
votes
1answer
131 views

Debugging FMW memory usage near Group-based Transformers

I have a large FME FMW file which is using a lot of memory at runtime. I have been tasked with trying to find ways to reduce the memory footprint. Early on in the workbench there is (what I assume ...
2
votes
1answer
873 views

ArcObjects: How to create a composite Geotransformation and use with the GeoProcessor

Using arcobjects, I am trying to programmatically create a composite geotransformation and then use to project features with the geoprocessor. Found old VB6 code out there on the web, but I can't ...
1
vote
1answer
357 views

Issues with defining projection to that of the current root file

I am creating a shp file with the extent of all the raster file in a set of directories and it works fine when all the rasters are in the same projection but not when they switch around. So I want to ...
1
vote
2answers
2k views

How can I get the values returned by an OpenLayers bounds object in Longitude / Latitude format?

I've created a map and added a layer using the Open Layers library: map = new OpenLayers.Map('map'); var gphy = new OpenLayers.Layer.Google("Google Physical", {type: G_PHYSICAL_MAP}); ...
1
vote
2answers
1k views

How to convert data in NAD83 (NSRS 2007) to NAD83 (CORS 96)?

I'm quite a ways outside my box on this one, but I would ceratinly appreciate any perspectives on this issue. I have some control points from NGS that are in NAD83 (NSRS 2007) that I would like to ...
2
votes
2answers
2k views

Getting a Bounding Box in Latitude / Longitude using PostGIS shp2pgsql

Using the PostGIS shp2pgsql -s 4326 ... I generated the sql file and created my spatially enabled table. When executing my query: select box2d(ST_extent(the_geom)) from feature_data; I'm returned ...
10
votes
4answers
1k views

How to reproject spatial data using free libraries?

How can I use free libraries to transform spatial data? For example, I want to change the projection of a Shapefile within the code of my C# web application. How do I do that?
11
votes
3answers
4k views

How to move vectors to specified coordinates in QGIS?

I have a layer of vectors located around, say, (100, 100), and I want to move them to new coordinate like (1000, 1000). How should I do it? Preferably using QGIS.
6
votes
4answers
6k views

How to reproject base layers in OpenLayers?

The issue is: I have vector/topo/image tiled maps for some places in north america which were published as ArcGIS Server REST service. These maps (A) are based in EPSG26912 projection. Now I wanna ...
2
votes
1answer
535 views

Postgis: WGS84 Lat Lon Point to Gauss-Kruger 3

How do I convert a WGS84 lat lon point in postgis to Guass Kruger 3 (31467)? Somehow, I do not seem to get it right. I tried the usual way for converting projections: ...
2
votes
1answer
737 views

How to provide transform information to openlayers on Image layer

I would like to include an overlay raster layer into my OpenLayers map. I've pre-transformed the image into the correct projection (EPSG:900913) and saved as a png using the gdal_translate command: ...
4
votes
1answer
227 views

Access is Denied error on ProjectEx call

I need to be able to convert a lat/long coordinate into a point coordinate and am having trouble getting my code to work. I created a test app isloating the code that is giving me problems. I'm ...
1
vote
2answers
1k views

Online service to transform coordinates from WGS84 to NZTM and NZMG

Has anyone come across a free web service / REST API to transform coordinates? I'm particularly interested in transforming from WGS84 to: New Zealand Geodetic Datum 2000 (NZGD2000 / NZTM) and New ...
2
votes
3answers
2k views

Transform Data with Microsoft Spatial SQL

Is there a way to transform geographic data in SQL Server 2008 R2? Specifically, I want to take Lat/Long data and convert it to a State Plane coordinate system.
3
votes
2answers
450 views

How to detect MGRS/UTM zone?

I posted a similar question on StackOverflow, but I thought I'd check here as well. I am developing an open-source library for converting between coordinate systems, and I've run into a wall. I want ...
2
votes
3answers
975 views

Transforming shp files to projected coordinate system

I have some KML files, polylines. I will convert them in grass to shp. How can I transform coordinates to some projected coordinate system? I was never doing it, so please help me. I need to transform ...
9
votes
2answers
7k views

Converting projected geoTiff to WGS84 with GDAL and Python

Apologies if the following question is somewhat stupid, but I am only VERY new to this whole GIS thing. I am trying to convert some projected geoTiff images to WGS84 using gdal in python. I have ...
4
votes
1answer
3k views

Converting Lambert Conformal Conic to WGS84 using Proj.4

I am attempting to transform data from Lambert Conformal Conic lat/long and I am having some issues with the results. The shapefile I am attemtping to transform can be found here: ...
5
votes
4answers
675 views

Given long, lat, x and y, how do I find the projection?

I am using an app called farsite that outputs shapefiles that show how forest fires will grow. I am getting output in coordinates as X and Y values rather than (lon,lat) and am looking for a ...
8
votes
3answers
8k views

Coordinate System Transformation in ArcMap

For the Data Frame Properties on a map in ArcMap, what is the difference between selecting a new coordinate system and using a Transformation?
8
votes
1answer
581 views

WGS72 to NAD83- how to find correct transformation

I am trying to get this raster file to convert from WGS72 to NAD83, but ArcMap10 doesn't appear to have the correct transformation listed. Where can I find this transformation, and/or how do I import ...
3
votes
3answers
587 views

FME - Possible to return a value from workspace?

I'm calling my workspace from the command line (either via Python or .NET to a system/os call). I'm parsing DWGs and pushing attributes to SQL Server in the workspace. Either the data validates in the ...
6
votes
2answers
3k views

How should I use GDAL to perform a transformation?

Greetings, I am a student who wishes to use GDAL to transform a series of images from Lambert Conformal Conic (EPSG: 9802) to Google Earth's WGS 84 (EPSG: 4326) for a web mapping project. I know ...
4
votes
1answer
2k views

Convert Gauss-Kruger to UTM

How to covert Gauss-Kruger coordinates to UTM coordinates with GeoTools java library? As I have figured out the location (zone, country) is important. I need the calculation for Slovenia.
6
votes
1answer
7k views

How can I transform GCS_North_American_1983 to GCS_WGS_1984?

I posted a thread today describing a shift in some of the NRC data (not all). Apparently, this shift has to do with conversion between Geographic coordinates, latitude and longitude and Transverse ...
14
votes
3answers
1k views

Rubber sheeting in GRASS or QGIS

We are in the process of getting our property boundaries corrected and a side effect of this is that we need to move any assets that have been drawn relative to the property boundaries, so they are ...
6
votes
3answers
759 views

Retrieve polygon smallest MBR

I have a postgis table containing polygons. I want to transform my polygons to 4 points polygons : retrieve the smallest MBR. Here comes an illustration of what I want : My original polygon is ...
7
votes
1answer
2k views

How do I get a country border data set into my geography column?

I have a PostGis database with a multipolygon geography (as opposed to geometry) column. I'd like to fill it with the country border data available from ...
3
votes
1answer
651 views

Ordnance Survey data to WGS-84

Recently I have reprojected Ordnance Survey data from British National Grid (ORD SURV GB) to WGS-84 using ArcGIS 9.2. After re-projecting I have found some shift in the data. Can any body guide me ...
5
votes
2answers
564 views

Why are the coordinates transformed with proj.4 off compared to http://valdemar.kms.dk/trf/?

I am trying to transform from epsg:4326 (wgs84) to epsg:25832 (utm ETRS89) using Proj.4. I am comparing the results with results from http://valdemar.kms.dk/trf/ . it seems like the results ...
3
votes
1answer
297 views

Is a WMS map always a constant scale?

If I get a map back from a WMS server is the scale always constant over them map regardless of the reference system? So if I have a map which is 100 pixels wide, will the point at 50 pixels always ...
3
votes
2answers
850 views

Which ESRI defined geographic transformation do I need to use to convert my “ NAD83 Northern Virginia” data into WGS 1984 Web Mercator?

My title pretty much tells it all.. I have a number of datasets in which I want to batch project from NAD83 Northern Virginia Datum into the correct Web Mercator projection.. When I do a straight ...
11
votes
6answers
565 views

Where can I find GIS data to test GIS coordinate operations?

I am trying to find some data that can be used to test GIS coordinate operations from one CRS to another CRS. So far all I have found is the Gold Data set and also various example points in the EPSG ...
5
votes
5answers
6k views

How to convert coordinates from Gauss-Krueger to Longitude/Latitude?

I'm a newbie in the GIS world so please advise me :) In my .NET/C# project I need to show some shapes/points on the Bing Map. The problem is I have the Gauss-Krueger coordinates and need to convert ...
1
vote
2answers
414 views

CORS - HARN transformations - what is the most accurate method

This may not be an issue for many GIS-ers but has anyone else had experiences transforming from modern NAD83 (CORS) to HARN coordinates and vice versa? I realize the discrepancy might be something ...
2
votes
1answer
442 views

How to convert SHP/POSTGIS data into x, y, z, “cost” data?

Is there a way to convert a line layer (shp or PostGIS) data into (x, y , z, cost) i.e. (From_node, To_node, optional_Elevation, Cost/Weight) ?