okay, so i have these avi files that read as avi's, yet when i play them, i get an error in vlc saying something akin to "wmv3 codec, can't read". i did a little research and found that ffmpeg may be able to help me in my mission to play these files, but i am unclear as to how. do i have to re-encode them? i really don't even know what ffmpeg does. can anyone help? thank you.