Crushing the blacks refers to making the blacks, SUPERBLACK.
Take some video footage and apply a levels effect to it. Take the video imput slider for black and move it to say 50. That would be crushing the blacks. If you look you can adjust both the RGB or Alpha channel. They adjusted the alpha channel, and made the blacks superblack. This affects the video levels, but gives them a cleaner key. You can see when they crush the blacks, how the video level comes down, in the video.
The gradiet fill is achieved by creating a ramp. Create a solid, add the ramp effect, then lay it over your video. You can use the siloutte luma transfer mode, or the luma track mode of the video layer. Will give that soft edge.
Afterwards, they rendered it out with a alpha channel.
The elements have alpha’s, that how transparents are created.
Johnny Cuevas, Editor
http://www.ckandco.net