I'm not sure if IMAQ or NI-Vision can do this for you. An alternative would be to see if there's an ActiveX control that will has properties and methods to save individual frames. If you're running on Windows you can check to see if Windows Media Player can do this - I don't know off-hand if it does. Another alternative is to use a third-party app that will do this. You should check to see if it can be called from the command line so you can call it from LabVIEW using System Exec.