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Importing Google Earth Imagery Into A GIS



This post has gotten a very strong reaction from many people, mostly negative. They say use of Google Earth imagery in the manner outlined here is inappropriate, an illegal violation of the Google Earth EULA/TOS. More specifically, words like “theft”, “stealing” and “dirty” have been used to describe this. I feel that this use of Google Earth imagery for personal and non-commercial uses falls under the guidelines of “fair use”, and I explain why here. “Fair use” is not theft. But I acknowledge that I could very well be wrong about this falling under the umbrella of “fair use” protection, in which case it would be illegal. I’d welcome opinions from those knowledgeable about the rights and limitations of “fair use”, and will pull the post if an expert on these issues says that using Google Earth imagery as described below doesn’t constitute “fair use”.

You can save the displayed view in Google Earth by using the File=> Save => Save Image command (Ctrl-Alt-S is the shortcut), which saves the contents of the view window as a JPG file. But in order to use this image in a GIS program, it has to be georeferenced, i.e. coordinates assigned to the pixels. There are free image georeferencing options out there, and I’ll cover some of those soon, but that’s not necessary in this case – there’s a simpler way to get the georeferencing data for an image exported from Google Earth.

You will need to have installed Google Earth (of course), the free GIS program MapWindow, and the Shape2Earth plugin for MapWindow. Shape2Earth’s main function is converting shapefiles to Google Earth KML files, and while the full version costs $29.95, it will work in unregistered demo mode for up to 500 shapefile vertices, and here for georeferencing Google Earth imagery.

1. Open Google Earth, and zoom in to the area of interest.

2. Double-click on the “N” in the compass at the upper right to orient north to the top of the screen. Also double-click on the “0 tilt” icon (the box with the “X” in it on the left in the tilt adjustor) to set the tilt angle to zero.

3. Open MapWindow; if you haven’t already activated the Shape2Earth plugin, do so from the plugins menu.

4. From the Shape2Earth menu in MapWindow, select “Get Image from GE”, and click on the “Capture Image” button. If you haven’t already oriented the image with north at the top and zero tilt, you will be prompted to do so.

5. Save the image with the desired name as a JPG file. This will save a black-and-white jpg image of the current view in the Google Earth window, along with a worldfile (*.jpgw) containing the georeferencing information.

6. Go back to Google Earth, and without moving or changing the view in any way, save the current view (File => Save => Save Image) with the same name and location as the image in step 5,. This overwrites the previous black-and-white image with a color one of exactly the same area.

You now have the Google Earth image with the georeferencing data contained in the worldfile (geographic coordinates, WGS84 datum), which most GIS programs can open and read successfully. If there’s a problem, try changing the extension of the worldfile from *.jpgw to *.jgw.

Limitations of this approach:

  • The view in Google Earth is orthographic, i.e. you’re looking at a sphere from above. For views that are zoomed to view a relatively small area, the area is essentially a flat plane, and the georeferenced image shouldn’t have a large deviation from the true coordinates. The larger the area covered, the greater the deviation between the true and georeferenced coordinates.
  • Coordinates in Google Earth can be off from the true coordinates even for small areas; see this post for more info. This process doesn’t correct for any such deviation.
  • Imagery in Google Earth is copyrighted, and using it for any other purpose than viewing in Google Earth falls under the restrictions of copyright law and fair use. In particular, you have to leave the Google logo and copyright notices unaltered to maintain proper attribution.

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18 Responses to “Importing Google Earth Imagery Into A GIS”


  1. 1 Erik

    Odds are if you are a user of a real GIS app then this use of google’s data is not allowed by the GE license. ;)

  2. 2 Frank Taylor

    I’ll second what Erik just said. Anyone planning to use an image from Google Earth for a business application should read the GE user license first. The imagery in Google Earth is mostly restricted by those who have licensed it to Google. You can seek permission to use imagery from Google Earth, but some of the license holders will require you to buy the imagery for a business application, or not allow it. Some of the imagery is license free (like those from NASA).

  3. 3 Erik

    GE’s license doesn’t distinguish between their public domain data and their commercial data, so you are better off getting PD imagery directly from NASA or the USGS, or just take your screenshot in World Wind instead. ;)

  4. 4 Leszek Pawlowicz

    I’ll take my layman’s shot at the usability question in an upcoming post. But for public domain imagery, you can get higher-quality georeferenced versions of the imagery used in WorldWind from the USGS Seamless Server, or one of the Terraserver programs I’ve talked about in earlier posts.

  5. 5 mdsumner
  6. 6 Aussie Sarah

    I am a reseach student looking at using Google Earth for my project. Does anyone know what their view about the use of imagery for research purposes is?

    Cheers

    Sarah

  7. 7 Leszek Pawlowicz

    I don’t know what the copyright/fair use laws are for Australia, so I don’t have an answer for you. Google Earth does have a program that offers free copies of Google Earth Pro for qualified non-profits; if you’re eligible for that, it would probably mean you could use Google Earth for your research without any worries.

  8. 8 Thomas

    Touratech QV 4 can also grab images from GE to a GIS map.

    30 days demo version:

    http://www.ttqv.com/main.php?content=21&download=13

  9. 9 imran elahi

    how can i use google earth images in gis for chitral, when ever i try i came across with some complications.

  10. 10 Nick McW

    This is really neat, thanks for posting. Have you tried it with GE Pro? I’m just asking since GE Pro saves images with a lot more resolution (4800 pixels rather than 1000 pixels – see http://earth.google.com/product_comparison.html). So, I wonder if the b&w image that Shape2Earth makes (step 5) will have the same resolution as the colour image saved by GE itself (step 6)? If the resolutions are different, then the pixel size values in the JGW will be wrong (although the corner coords will still be correct, I expect).

    Also – any idea why Shape2Earth saves B&W, not colour?!?! Seems odd.

  11. 11 Dan

    I did try this, and Nick (above) nailed it. The GE Pro 4800 pixel image does not match the referencing of the Shape2Earth B&W one. This could probably be corrected by mucking with the pixel values, but I couldn’t be bothered. I went with the method described here instead: http://forums.esri.com/Thread.asp?c=93&f=1740&t=193459&mc=3#575260.

  12. 12 Nick McW

    Just tried GE Pro at last – it’s great, in that it saves images at up to 4800 pixels horizontally. The vertical image size depends on the window size and whether the sidebar view is on. In full screen mode, I get 3765 pixels vertically, but I guess it would go up to 4800 x 4800 pixels if I stretched GE over two monitors or had a particularly hi-res display. I now get a c. 18 megapixel image rather than a 1 MP image. Looked at another way, a saved image covers almost 5 km x 4 km at 1 metre resolution.

    However, I found the same as Dan, that the Shape2Earth extension for MapWindow only correctly references the basic 1000 pixel image. So I made a simple spreadsheet to “muck around with the pixel values” (I like the phrase!) and calculate the values needed for a worldfile for the 4800 pixel image. It’s rather clunky, requiring the user to copy the North, West, East and South extents of the bounding rectangle from the S2E dialogue and paste them into Excel, then to copy data out of Excel and paste it into a .jpgw text file. However, it does seem to work and is probably a bit quicker and potentially more accurate than georegistering in ArcGIS.

  13. 13 Leszek Pawlowicz

    Thanks, Nick. Any chance you could post a link to that spreadsheet? Unlike Google Earth Free/Plus, there should be no argument about using Google Earth Pro imagery in this manner.

  14. 14 Nick McW

    Hi, here’s the spreadsheet as a Google Document:
    http://spreadsheets.google.com/ccc?key=pWkKqjyOK8PkuHvEJ4QXcRQ

    To use it, you’ll need to export from Google Docs to your PC:
    Google Docs > File > Export > .XLS

    Improvements welcome of course……

  15. 15 Carlos

    My company does have a licence to use google earth’s images in our work.

  16. 16 oyunlar

    With google earth plus??

    “My company does have a licence to use google earth’s images in our work.”

  17. 17 kral oyun

    Thanks, Nick chance you could post a link to that spreadsheet? Unlike Google Earth Free/Plus, there should be norgument boutusing Google EarthPro imagery inthis manner.

  18. 18 Vikas jyani

    I have captured the google earth snapshots and mosaiced them to make a complete study area.

    for my college project work. is it illegal an unfair.

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