If you have After Effects available to you I would suggest going that route. Export as a Quicktime or QT ref and then draw the matte with the pen tool with RotoBezier’s active. Create your matte keyframes at the first and last frames first. Then go to the middle and create a key, then go to the middle of those two sections and create another key. Continue working from the middle until you have the desired results. The key (no pun intended) is to do it with as few keframes as possible. Combustion would be another route if you have that, I actually prefer it to AE for rotoscoping. As for doing it in Photoshop I