The Action Buttons appear in the tool bar along the top of the screen. Generally, they are used to quickly and interactively move the overlay image into position. Most of the buttons auto-repeat, so if you hold them down, you can quickly pan or zoom the the image.

You can also do this by directly dragging the image and the frame around the image with the mouse. This is usually quicker and more intuitive than using the buttons.

However, the buttons can be used to do very small increments that are difficult to do by hand.

1. Reset Button. The Reset button resets the overlay image to its original size and position.
 

2. Increment Tool. Each time one of the Pan, Zoom or Rotate buttons are pressed, the value changes by a certain amount. The Increment Tool controls that amount. Large values allow you to quickly change the overlay; small values allow you to control the overlay very precisely.
 

3. Pan Buttons. The Pan Buttons allow you to move the overlay  image left, right, up or down.

4. Zoom Buttons. The zoom buttons allow you to scale or increase or decrease the size of the overlay.

5. Rotate Buttons. The Rotate Buttons rotate the overlay around  its center.

6. Merge Button. Pressing the Merge Button causes the current overlay image to be merged with the main image. The exact position and transparency is preserved so the image are combined exactly the way you see them.

7. Undo/Redo Buttons. Click here for a complete description of the undo/redo functions