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.
4
votes
4answers
3k 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 ...
5
votes
2answers
2k views
Rotating a vector layer in QGIS with qgsAffine (or other method)?
I would like to rotate a set of vector points in QGIS an arbitrary number of degrees around a central point (or arbitrary point).
This is similar to a recent question about creating a regular grid; ...
5
votes
1answer
860 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 ...
6
votes
2answers
2k 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 ...
13
votes
3answers
959 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
615 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 ...
5
votes
1answer
413 views
How to reproject a raster file in QGIS with datum transformation?
I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
4
votes
1answer
1k 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 ...
3
votes
2answers
686 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 ...
6
votes
2answers
4k 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 ...
9
votes
4answers
624 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?
3
votes
1answer
111 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 ...
1
vote
1answer
517 views
How to perform transformations using ProjNet?
While writing some unit tests I thought it would be convenient/possible to use ProjNet to convert from EPSG:4326 into several other coordinate systems (3875,3395). I figured it would be as easy as ...
5
votes
4answers
590 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 ...
3
votes
1answer
159 views
getting the specified geographic transformation, or at least the GCS, of a data frame
First, the TLDR digest:
I'm getting a bogus value from dataFrame.geographicTransformations on some machines; how do I get the correct value as shown in the properties dialog? and/or
Given a spatial ...
3
votes
1answer
525 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 ...
2
votes
2answers
63 views
Where can I get the list of Geographic Tranformations in ArcGIS and the area where they are aplicable?
I have some data in Provisional South American Datum 1956, and I need to project it to Web Mercator with WGS84 as the datum.
When I use the project tool in ArcGIS desktop, it requires a Geographic ...
2
votes
1answer
56 views
Setting coordinate systems in QGIS: “transform error caught”
I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
2
votes
3answers
924 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.
1
vote
1answer
130 views
ArcObjects 10.1 .NET Convert Point from WGS1984 to OSGB1936
Please can someone help me convert a point in WGS1984 to OSGB1936, I have followed all the documentation (or so i think...) and yet have not made any headway into this problem. This is my code :
Type ...
0
votes
2answers
264 views
Setting spatial reference for MapInfo tab-file
How can I change spatial reference for tab-file in MapInfo Professional?
