i was just trying out the trial version of Flash CS5 and the Media Encoder. I tried to encode some mpeg2 files as f4v, but the media encoder says it cannot decode mpeg2-files. The help topic (http://help.adobe.com/en_US/mediaencoder/cs/using/WS725e431141e7ba651e63e3d1267818bc51-800 0.html) says: "Depending on what other software you have installed, the following options may be available: ... mpeg-2..."
so i was wondering which piece of other software i need to use mpeg-2 as input format for the media encoder.
On the Mac I think you need QuickTime Pro and the the MPEG-2 component. I think they make it for Windows as well.