Oki S900 - Manual (Page 36)

USING THE S900 AS A SCANNER > 36
MIRROR
Click on the Mirror button to reverse the image (create a
mirror image).
AUTO SELECT IMAGE
Clicking on the Auto Select Image button automatically sets
the whole area as the scan area. You may resize the area by
dragging the mouse pointer diagonally.
PAPER SIZE
Select a size on the Paper Size list of frequently used scan
sizes, or your current scan area to perform an immediate
selection of your scan size.