Monday, January 28, 2008

Ripping and Georectifying Google Earth Images into ArcGIS

This article, of course, is for entertainment purposes only - Google Earth data is not to be used for any commercial purposes. I will try to describe how to move images from Google Earth to ArcGIS as seamlessly as possible. Google earth is great, but you cant perform any real or lasting analysis with it. So, how does an imagery enthusiast get the images from GE to Arc?

Methodology

1. Place 3 or more placemarks at the edge of the portion of the Google Earth image you wish to move to ArcGIS


2. Save each of them in Google Earth (they can be found listed in the My Places folder).


3. Import the points to ArcGIS with ET Geowizards

You can find a more detailed article about importing and exporting to/from Google EArth to ArcGIS

here : exporting from GE
and
here : importing GE points into ArcGIS 9.2

One you have added each of your points as a point feature in ArcGIS, you now need to import the Google Earth Image itself. The only way to do this - that I currently know of - is the following:

- Turn off all layers in Google EArth so you just see the satellite image/air photo
- press alt+print screen to dump your screen's image to the clipboard
- paste the image into a paint/image program
-save the image as an ESRI compatible format (be sure to leave the Google Earth Copyright information on the image as well as the company who provided the data to Google).
- Add the image into ArcMAP

Once you have the image in ArcMAP, it does not have any coordinates. In this situation you need to georectify it to fit the 3+ points you recorded earlier in GE. If you do not know how to georectify an image, be sure to follow my guide at: