Roger,
The video I saw said you copy the elements you don’t want, or whatever they’re called, to an new layer and then invert the phase, effectively cancelling it out. I don’t have it to work with, but it should work.
Jeff
2-Xeon X5680 @ 3.33, EVGA SR-2 Mobo, 48GB DDR3, GTX 580 3072MB, 16TB Attached Storage, Win7, Vegas 11 x64