The Coordinate Plane · Hard problem

A picture frame is drawn on a grid. The outside edge of the frame is a rectangle with corners $(0, 0)$, $(10, 0)$, $(10, 8)$ and $(0, 8)$. The hole for the picture is a rectangle with corners $(2, 2)$, $(8, 2)$, $(8, 6)$ and $(2, 6)$. What is the area of the frame itself (not counting the hole), in square units?