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***    Image Georeferencing Tools -- Documentation    ***
***  Author : George Raber  email - George@Raber.com  ***
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The extension works with ArcView 3.1 to postion images
within geographic space.  The user may also change the 
size of the image.  Movement of the image can be done
in do different ways, either through the dialog box or
by drawing a line.  Insttructions are below.

1. To install this extension place the file called 
   imagegeoref.avx into the "ext32" folder where 
   ArcView 3.1 is installed on your hard drive.

2. Get into ArcView 3.1 and load the extension by
   using dialog that can be reached in the project
   menu.  Once this is done you should have three 
   new buttons, a menu, and a tool added to the
   "View" GUI interface.

3. Load the image (as an Image Theme) that you 
   want to GeoReference.  Also load any reference 
   themes you need to do this.  Make the Image
   theme active, then you will notice most of the
   new buttons and tools will no longer be greyed 
   out.

4. Start out by pressing the button that has a blue
   gradicule on it.  If the image has no world or 
   header file it will prompt you to enter information
   to create one.  For most images you will create
   a world file.  Instructions for what parameters
   you need are in the ArcView help and documentation.
   There are also helps provided in the dialog.

5. If an world or header file exists, or after you have
   created one, press the blue gradicule button.  Then
   the georeferencing file will be displayed in a text
   box in a dialog window.  You can edit this file 
   directly by pressing the "Edit File" button.  When
   done press the "Save File" button.  When you press
   "Save File" the Image will update according to your
   new parameters.

6. You can also press the "Show Controls" button.  A
   number of controls will show up under the file.
   You can change both the position and size of the
   image.  After changing the information you need to
   press the appropriate Go button the image and the
   text box will then update based on your input.

7. The other way to shift the postion of the image is
   to click on the last tool in the "View" GUI.  Then
   click on the View window and drag a line on it.
   The image location will then update itself, and the
   view will then refresh.


Extra Notes: 

	1 - If the image is the only theme in the view
	    no effect will be seen because ArcView centers
	    the theme in the view window if only one view
            is present.

	2 - Georeferenceing can be undone as long as the user
	    keeps the current theme active, or switches back
            to the theme before changing to another image theme.
            The undo/redo items are avalible both in the image menu
            and the popups.  

	3 - The other buttons that are added to the View GUI
            preform portions of what the other buttons do.
	    The first adds a header or world file to an active
            image theme.  The second refreshes the view window.      