TYPE: COP
TITLE: Pin COP

This operation allow you to fit an image into an arbitrary quadrilateral, 
which allows you to do simple perspective tricks, shearing and fitting.

Four points are used to pin the image and represent the different corners of
the input image.

Parameters
Corner Pin
    Units             - Specifies the units of the point coordinates.
    Bottom Left, Bottom Right, Top Left, Top Right - The four corner points
                                                     of the image.
    Filter            - The filter to use when scaling the image to fit
			the new area.

Plane Scope, Frame Scope
    Overview - See extra help (Middle click on the dialog '?' help).

Local Variables:
    L   - Sequence length
    S   - Start of sequence
    E   - End of sequence
    IL  - Input sequence length
    SR  - Sequence frame rate
    NP  - Number of planes in sequence
    W,H - Width and height of image
    I   - Image index (0 at start frame)
    IT  - Image time (0 at start frame)
    AI  - Current plane array index
    PI  - Current plane index
    PC  - Num of channels in current plane
