Tagged Questions

5
votes
1answer
62 views

Georeferencing a jpeg in QGIS but the scale is way off

I've gone through the really helpful walk-through(s) of how to georeference a jpeg in order to make it a layer, but after inputting the coordinates (either by typing in actual coordinates or clicking ...
8
votes
1answer
114 views

What is some theory on the number of GCP when georeferencing?

Just wondering, is it always better to have more than 3 GCPs? Should the GCPs be spread out evenly? Where can I find some general resources on the theory of this? Other than trial an error, which ...
13
votes
3answers
194 views

Which CRS would you use to georeference historical world maps?

Which CRS would you recommend to georeference historical world maps like the ones in the London Geographical Institute - The Peoples Atlas - 1920, e.g. The map displays a lat/lon grid which I would ...
0
votes
1answer
56 views

Can you use a large file directory of jpgs for without georeferencing

I have a large map data set of 256x256 jpg images. The file directory is organized by /map_type/zoom/x/y.jpg. I have 12 zoom levels and each zoom level directory has 2^(2*zoom level) images. I have ...
1
vote
2answers
125 views

Why is Format of output data grayed out on Save As dialog for Rectify?

I started georeferencing and I could not save my new "rectify" file, I don't know if is because of the raster or I did something wrong. Then I find out that my control layer is not accurate, it ...
2
votes
2answers
214 views

How to georereference a TIFF file which has already a spatial reference?

I have a TIFF file of Poland and a self drawn vector map of Poland. The vector map has no spatial information. I am intending to reference the TIFF exactly to the shape of the self drawn map. My ...
4
votes
0answers
187 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 ...
1
vote
0answers
55 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 ...
1
vote
1answer
143 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 ...
0
votes
0answers
140 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 ...
3
votes
1answer
216 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 ...
3
votes
3answers
491 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 ...
1
vote
1answer
190 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 ...
2
votes
1answer
243 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 ...
3
votes
3answers
277 views

Georeferencing a whole heap of raster imagery

I have a whole heap of satelite imagery coming in that is not georeferenced. They have a grid overlaid so I do know the bounding box/coordinates of the images (and projection). I just need them ...
3
votes
1answer
265 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. ...
5
votes
4answers
725 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 ...
5
votes
1answer
228 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 ...
3
votes
2answers
781 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
3k 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 ...
9
votes
1answer
412 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 ...
19
votes
7answers
1k 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 ...