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

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20
votes
5answers
7k views

How to determine if a tiff is georeferenced or not?

I received a tiff file from someone, but I'm not sure if it's georeferenced. Is there an easy way to check this?
3
votes
1answer
758 views

Automatically georeference hundreds of png files based on polygon vector coordinates

I have 1000 polygons in my shapefile. I also have 1000 PNG files. Do you think it is possible (based on a common attribute), through a script or something, to assign each of those PNG files to a ...
0
votes
1answer
2k views

How to set up QGIS + georeferencer for easiest georeferencing

The goal is to make converting scanned paper maps to map tiles as easy as possible. I've done a few, but the slow part is manually entering coordinates of points. What I'd like to do is for each ...
6
votes
3answers
16k views

Steps to creating a GeoTIFF

First off, I'd like to mention that I'm pretty new to working with GIS, so please forgive my inexperience. My situation is as follows: I'm tasked with georectifying a set of imagery and importing ...
3
votes
1answer
439 views

How can I georeference a second image without losing georeferencing for first image in ArcGIS 10?

What happens: 1) Take a map with an image that was georeferenced earlier, which works fine. 2) Add a second image to the TOC and fire up the georeferencing toolbar. 3) Select the new, ...
2
votes
0answers
235 views

GIS “hack”: ways arbitarily assigning coordinate in order to match the raster and vector layer in QGIS

Before I raise my question, I have to admit that I am a total newer on GIS, I don't have much background on GIS. But suddenly I need to take over the GIS job from a GIS specialist who just left the ...
3
votes
1answer
487 views

Georeferencing multiple rasters to World files

I've got exactly 56 tiffs to georeference. Each raster has its unique TFW world file. I'd like to automate this process. Each raster has it's unique name which is consistent with world file name (eg. ...
3
votes
3answers
1k views

Georeference to x y coordinates with one lat long origin?

We are running parallel transect lines for a survey, which will roughly cover a rectangular area. When making the transects, we will periodically capture spatial locations of features and events we ...
4
votes
2answers
887 views

How do I specify a CRS for a fictional game map in QGIS?

I am about to start playing a steampunk RPG game called The Iron Realm, which uses a fictional world map. I have recently started using QGIS v1.7 and have no real experience with GIS sysstems. I have ...
5
votes
3answers
1k views

Help required to convert georeferenced (and rectified) TIFF orthophotos to georeferenced .JPG format

I am not a GIS specialist (so patience required!) :) We work with georeferenced, rectified 1:10 000 orthophotos. I need help with the conversion of a georeferenced tiff to a georeferenced jpg. Our ...
4
votes
1answer
598 views

Extract coordinates for series of georeferenced files in ArcGIS 10?

I have a series of 1900 spatially continuous images that are georeferenced. Each image is a tif file paired with a tfw file. These images are easily open and shown in ArcMap 10. However, I need a way ...
7
votes
2answers
3k views

How to generate world files for raster X?

Given a list of georeferenced rasters, about a hundred, what is the simplest method to generate world files for each? In this case the source rasters are either geotiff with embedded georeferencing ...
2
votes
1answer
206 views

QGIS 1.7 + MacOS 10.6 : georeferencing from map canvas bugs

I am experiencing issues with the gdal plugin to georeference a raster. It works fine when I enter the coordinates manually but it does not work when I try to link the plugin with the map canvas. ...
3
votes
1answer
2k views

Georeferencing with Quantum GIS and reprojecting to EPSG:900913

I'm trying to reproject a map to EPSG:900913 The image I'm reprojecting is the following http://i.imgur.com/HmfLW.png I'm using the cities as reference points obtaining the coordinates from Google ...
5
votes
4answers
1k views

How to generate a world file with rotation

I`m writing code to geo reference some images that I get with a rc plane. I have the central coordinate of the image because its atached to the center of the plane. But I have problems when I open the ...
6
votes
5answers
1k views

Georeferencing aerial photos when only centroid is known using ArcGIS for Desktop or ERDAS Imagine?

I have heaps of aerial photos that need to be georeferenced. I have access to ArcMap and ERDAS. All I am given is an excel sheet with the centroid coordinates of each image. Each photo covers ...
1
vote
3answers
7k views

How to georeference a scanned map in ArcMap 9.3?

I want to georeference a scanned map of Sudan (Africa) as .jpg file format,coordinate points are marked on scanned map in 4 degree intervals. I am not familiar to georeferencing in ArcMap. So looking ...
5
votes
1answer
324 views

Unknown Coordinate System on old drawing

I work with many old civil engineering documents, and occasionally I'll need to georeference one which has coordinates pairs listed at many given points but does not list which coordinate system these ...
7
votes
3answers
7k views

Generally accepted root mean square (RMS) error for rectifying topographic maps

This is a generic inquiry on the common practice/standard for determining the acceptable values of RMS when georeferencing topographic maps. Is there an absolute value? Some literature suggests that ...
3
votes
2answers
931 views

Change output file type in QGIS georeferencer?

I have successfully georeferenced a raster file via the Georeferencer plugin (Georeferencer GDAL Version 3.1.9) in QGIS 1.7.0. However, I noticed that the output georeferenced raster file is in TIFF ...
5
votes
2answers
4k views

Convert x, y position in georeferenced image (with world file) to longitude, latitude?

What steps do I need to do in order to calculate longitude and latitude for a specific pixel in a georeferenced image? For example this image ...
2
votes
4answers
3k views

GIS newbie, How to georeference a jpeg metro map using OSS?

I have a metro map in jpeg format and I want to georeference it. My goal is to find GPS location of the metro stops and visualize them on google maps. Probably, the first step is to overlay the map ...
4
votes
0answers
496 views

How to digitize directional drilholes from scanned vertical sections? [duplicate]

I need an advice how to do this. Normally, I either receive a file containing drill holes or at least data with xy position, direction, depths and attributes. I then use this data for further ...
13
votes
7answers
2k views

Best method to georeference oblique photographs?

I have a series of oblique photos taken from an airplane of oyster beds that need to be mapped. Does anyone have any tips on georeferencing oblique images? I have access to ArcGIS and ENVI.
7
votes
1answer
1k views

automated georeferencing

I am attempting to fully automate the process of georeferencing a load of .png files - i have xml file containing the co-ordinates - but how can i use them? Does anyone have any advice?
2
votes
1answer
672 views

Georeferencing help (GeoTiff into MapWindow6)

I'm a newbie with MapWindow6 and I would like to figure out a couple of things. 1 - Whenever I drag and drop a GeoTiff into the map (MapWindow6) I can not see that image at its place, I mean that ...
14
votes
1answer
1k views

Are there any general rules of thumb for selecting a transformation for Georeferencing?

There are several transformations that can be used when georeferencing a raster: 1st order Polynomial (affine) 2nd order Polynomial 3rd order Polynomial Spline... etc Are there any specific rules ...
9
votes
2answers
3k views

How can I transform a georeferenced JPG to a georeferenced TIF?

I have an georeferenced JPG file and a JGW file containing the coordinates. How can I transform it to a georeferenced TIF file and a TFW file? I have tried to save the JPG file as an TIF file in ...
0
votes
1answer
693 views

How can I open a georeferenced JPG file in OCAD?

I have a georeferenced .jpg file with the .jgw file containing the coordinates. I want to use it as a background in OCAD. But when I open the file as a background, the jpg file is not georeferenced to ...
3
votes
2answers
1k views

Is it possible to use more than two control point links when georeferencing CAD files in ArcMap?

I'm trying to georeference CAD to a building footprint in ArcMap 10 (although I've had this same problem in earlier versions). The problem is, it won't let me use more than two control point links, so ...
24
votes
7answers
2k views

Work flow for georeferencing imagery using open source tools?

Does anyone have a recommendation for a work flow for georeferencing high resolution aerial photography using open source tools? Comparison of user friendliness and robustness between Quantum GIS ...