Aligning geographic data to a known coordinate system so it can be viewed, queried, and analyzed with other geographic data.

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9
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1answer
11k views

Georeferencing shapefile using ArcGIS for Desktop?

I have a shapefile with some polygons that I would like to superimpose to a raster image, but unfortunately they don't match perfectly due to the reference system the shp has been created with. So, I ...
0
votes
1answer
435 views

How do I add a Corel Draw map as .dxf file to QGIS and how do I georeference it?

I have a vector data map of Poland, which I exported from Corel Draw. I can display the map in QGIS. At first the boundaries and subdivisions are only displayed as lines, after saving the data as ...
5
votes
1answer
899 views

Calculating distance in WGS84 (MySQL and Geoserver)

Here is the environment in which I work: An application using geo-referenced data Database MySQL 5.5, storing georeferenced points A Geoserver server, connected to the MySQL database Here is the ...
2
votes
0answers
136 views

Install Georeferencer Plug-in QGis 1.7.0 OS X

I'm trying to install the Georeferencer plug-in in QGis 1.7.0 on Mac OS X (10.5.8). However the plug-in doesn't show up in the list. I have used "enable 3rd parties directory" and I have checked ...
4
votes
1answer
174 views

How to stack rasters for ecological analysis?

The attached image shows two different forest openings. Each opening has the following layers associated with it: Point shapefile 1 = A red X which represent a large "legacy" tree in the gap Point ...
2
votes
2answers
483 views

QGIS' georeferencer layer doesn't appear?

I use QGIS 1.8.0 for Linux, and I want to draw roads manually on the map. So according some tutorials, I use Raster>Geoferencer>Geoferencer to import a bitmap image including roads, and set ...
3
votes
5answers
3k views

How to find coordinates for a lot of locations based on the town or village name?

I have got an Excel spreadsheet with roundabout 15,000 locations, which are only identified by the towns or villages name and the country. I am intending to present these on a world map. Therefore, I ...
5
votes
2answers
2k views

Display Georeferenced Images on Android

I'm looking for an Android application (best would be Open Source), that can display georeferenced images on top of a map (Google, OSM, ...). By Georeferenced I mean that the images four corners are ...
10
votes
2answers
1k views

How can I improve my Georeferencing results?

Background This is my second question related to georeferencing naked raster maps in order to re-visualize them on different coordinate systems and in conjunction with other data layers. The previous ...
2
votes
0answers
218 views

How to georeference an areal photograph given known coordinates of the four corners and center of the image

First, let me say that I am new to this field. I have an existing image/video viewing application. My primary goal is to implement an efficient method to determine the latitude and longitude of any ...
2
votes
1answer
716 views

How to georeference using Latitude and longitude in QGIS?

I'm trying to georeference a picture using Latitude and longitude. The points are these: top-left: (116.30950927734372,39.970805680527725) top-right: (116.35620117187497,39.970805680527725) ...
2
votes
2answers
836 views

Georeference information stored in tfwx (from ArcGIS). Is it possible to see the georeference in QGIS?

I have georeferenced some images (ArcGIS -> Update Georeferencing) which creates a *.tfwx file with the new parameters for georeferencing. I renamed it to *.tfw but QGIS is not able to read the ...
1
vote
1answer
499 views

How to convert images from the South African co-ordinate system to WGS84 lat/long?

I have a number of orthophotos for an area in South Africa, but they are projected in the South African co-ordinate system which measures a location in meters from a central (uneven) meridian. These ...
2
votes
2answers
712 views

How to create a “Datum-less” projection in QGIS?

I want to use QGIS to do some georeferencing and image registration. On ArcMap10 I can define an "Unknown Projection", basically a default metric grid, and use it as a grid for georeferncing. In QGIS ...
3
votes
3answers
808 views

DXF to georeferenced SHP

I know how to set projection and georeference bounds of scanned TIFF file, by using gdal, but I don't know how to do the same for vector file. For example I georeferenced TIFF file by using this ...
6
votes
1answer
577 views

Determining Natural Origin for a GeoTIFF file (Lambert Conic)

I am trying to display an existing GeoTIFF file (from the FAA WAC set) in an application that requires the GeoTIFF NaturalOriginLongitude tag (FalconView 5.1.1). There are some older files in that set ...
9
votes
2answers
303 views

Does a Scanned Map have to be georeferenced in the projection of the original Source?

I have a historic paper map for the Indian Sub-continent which has been scanned. The Map is in Albers Equal Area Conical projection, and has the latitude and longitude grid on it. I was trying to ...
1
vote
1answer
166 views

Transforming x/y co-ordinates of 'custom' map to 'real' long/lat co-ordinates?

I have in front of me a 'custom' map of an area I like to visit. It's just a representation of the area, so there's no real connection between the points on the 'custom' map (a) and how they would ...
0
votes
0answers
569 views

Why is “Convert Graphics toe Features” grayed out in a dataframe that has georeferenced layers?

I have brought two graphics, a species range and a heatmap, into a dataframe and georeferenced them using control points. I rectified them and now I want to clip one with the other but I can't get ...
7
votes
2answers
169 views

How to keep track of changes to geo-referenced data and maps?

At my company we are starting to get more serious about keeping track of changes to our geo-referenced data and maps. I'm looking into this and am wondering how people do it at other companies. We ...
2
votes
1answer
290 views

Is it possible to rectify an aerial photo with known control points in 3d, in QGIS?

Bonjour, Peut-on avec Quantum GIS redresser une photo aérienne avec des points caractéristiques connus en 3D (XYZ) ? -- Translation: Hello, Is it possible to rectify an aerial photo with known ...
1
vote
0answers
74 views

Create 6 band IMG file with GDAL out of two JPG files, one with WorldFile coordinates

I have two JPG files 1 ortomap: http://imageshack.us/photo/my-images/703/ortofoto1.jpg/ with WorldFile: 0.683772574816354 0.000000000000000 0.000000000000000 -0.683739485024190 ...
2
votes
1answer
2k views

Convert X Y Pixels to Easting Northing

I'm trying to find out what the formula would be to convert the X, Y of an image to the Easting and Northing coordinates. I've downloaded some of the raster maps from OS UK web site and I'm looking ...
1
vote
1answer
439 views

Georeference Raster File with WorldFile into an aerial photo using GDAL [duplicate]

Possible Duplicate: How can I transform a georeferenced JPG to a georeferenced TIF? UPDATE:Corrected link I must note that I am new to GIS so pleas be understanding. PROBLEM: I have a ...
2
votes
2answers
730 views

How to georeference a LANDSAT scene in QGIS 1.8?

I tried to georeference a LANDSAT scene in QGIS 1.8 but I failed. My first question is Can I use geografical coordinates as x,y coordinates of control points? or I need projected coordinates (from ...
1
vote
1answer
491 views

Georeferenced Tiffs displaying in the wrong location & scale when updating ArcGIS 10

I'm working on a project which involves georeferencing a large number of .tiff files to digitize data from them. All the tiffs which have already be georeferenced where done with ArcMap 10.0 without ...
0
votes
0answers
230 views

QGIS Georeferencer and Coordinate Systems

I'm having an issue with Ubuntu and Windows versions of QGIS where the georeferencer does not properly assign the coordinate system to the output raster. When I assign the output CRS to 'EPSG:900913 ...
0
votes
1answer
566 views

How to georeference CAD drawings without preserving aspect ratio?

I have a CAD drawing (DWG) format that I would like to georeference to my basemaps that are projected in UTM coordinates. This drawing is done to scale without any geographic referencing. In ArcGIS, ...
3
votes
1answer
574 views

Georeference problem including EPSG 102067 projection

I'm Qgis user from Czech Republic. We have a spatial national coordination system (Krovak system) having positive X axes pointing to the south and positive Y axes to the west. Many geographical ...
2
votes
1answer
1k views

How can I relocate a georeferenced image, shapefiles and grid using Spatial Adjustment tool?

I somehow georeferenced an image about 120 miles east of where I should have georeferenced it. This should be a simple fix, except that I then proceeded to digitize that extremely detailed image ...
10
votes
8answers
8k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
9
votes
3answers
525 views

How to outsource scanning and georeferencing maps?

We have some historical paper maps and we want to get them scanned and geo-referenced and ultimately make a seamless map for a particular time. What vendors supply this service? (I have found ...
3
votes
3answers
2k views

How to digitize polygons from georeferenced raster file

I used QGIS to georeference a raster file of a custom US map. The map has features which are not strictly defined by state borders. I would like to digitize the map by creating contiguous borders for ...
2
votes
0answers
139 views

Grid perspective tool

I'm not a cartographer, but want to use a map for my project from world atlas book. I scanned the map, but no matter how carefully it is scanned, it's perspective is slightly distorted and it's ...
1
vote
1answer
308 views

Help needed for georeferencing in QGIS

I am new to Quantum GIS. I just happened to browse to a tutorial on georeferencing in QGIS and I found it easy and interesting. I also calibrated the map and saved the points as per WSG84 standard. ...
6
votes
3answers
2k views

30,000 data points… can this be reasonably served using openlayers?

I'm trying to tackle a web GIS problem and need to figure out the best strategy. I have a map with 30,000 cells on it forming a grid for the province of Alberta. I have a list of data points for ...
2
votes
1answer
84 views

What should I expect in this case?

If while I'm executing gdalinfo against a raster layer I get a positive value for pixel size Y, what of these scenarios is possible? The raster's map coordinate system sets the origin of the data in ...
5
votes
5answers
12k views

Trouble when georeferencing CAD files in ArcMap

I've definitely got at least a couple of grey hairs while trying to convert some dwg. files to shapefiles. I've seen that this subject has been disscused a lot, but hope someone will have the ...
5
votes
3answers
2k views

Convert an arbitrary meta-data-free map image into QGIS project

My background: experienced programmer, amateur historian, complete beginner to GIS (so I'm using QGIS). I did learn to use the QGIS georeferencer tool though. The input: suppose I have an image like ...
3
votes
1answer
1k views

Why can't I download the georeferencing plugin for QGIS 1.7.4?

I used the georeferencing plugin with QGIS 1.6 and now that I've upgraded to 1.7.4 I'd like to do it again. But when I search for the georeferencer plugin, it's not available! Am I doing something ...
2
votes
1answer
449 views

How to add EPSG:5235 to QGIS?

First of all I should say I am new to EPSG and QGIS world.Then I want to Georeferced Raster image to EPSG:5235 in QGIS. But in Qgis I can't found above EPSG. How I add this EPSG to Qgis ? Pls help ...
12
votes
4answers
8k views

What is the difference between geocoding and georeferencing?

After some googling around both seem to be interchangable words, where we speak of tying the spatial info of a real place and storing in database. But still I am not satisfied, there should be some ...
1
vote
0answers
40 views

I want to georeference jpg map without having any digitizing data? [duplicate]

Possible Duplicate: I want to georeference jpg map without any digitizing data? I have only a jpg map but dont have any digital data for georeferencing that jpg.So is there any way for ...
1
vote
2answers
4k views

I want to georeference jpg map without any digitizing data?

I have only a jpg map but dont have any digital data for georeferencing that jpg.So is there any way for georeferencing my map (like googlemaps)?
3
votes
1answer
618 views

Transform multiple layers as one unit in ArcGIS 10?

The general/conceptual question: Is there a way to transform multiple layers together in ArcMap 10 (on Windows XP SP3) as one unit? More specifically: I have an ArcMap document with a georeferenced ...
5
votes
0answers
454 views

How to reverse-georeference with QGIS?

I have a map with a "strange" projection (it's basically hand-painted, not an exact one). I can easily georeference it in QGIS using the Georeferencer plugin and the Thin Plate Spline transformation ...
3
votes
1answer
608 views

How to create aux.xml file?

after starting to use MOBAC to create offline background maps I found the aux.xml files very useful as QGIS automatically sets the CRS so this would be very useful for my colleagues with smaller GIS ...
1
vote
2answers
2k views

OGR DXF to KML conversion

I'm trying to convert a DXF 2010 file to KML using ogr2ogr: ogr2ogr -f "KML" outfile.kml infile.dxf In the file, $INSUNITS is 6, that's meters, if I'm correct? The problem is that DXF is not ...
2
votes
1answer
525 views

QGIS Georeferencer - Image file imports too small

I am trying to georeference a largish aerial image (50MB) to some GIS data I have and import it as a background. However the image imports extremely small - so small I cant see it! I am using QGIS ...
5
votes
2answers
899 views

QGIS affine - form of equation

I am at the mercy of a govt authority who have provided utility information in a cad format with a 0,0 origin and a nonsense grid. About a dozen files, the grid and origin are entirely arbitrary. To ...