Corner Pin effect
The Corner Pin effect distorts an image by changing the position of each of its four corners. Use it to stretch, shrink, skew, or twist an image, or to simulate perspective or movement that pivots from the edge of a clip, such as a door opening.
Note: You can directly manipulate the Corner Pin effect properties
in the Program monitor when you click the Transform icon 
next
to Corner Pin in the Effect Controls panel. Drag one of the four
corner handles to adjust the properties.
next
to Corner Pin in the Effect Controls panel. Drag one of the four
corner handles to adjust the properties.