HD video and Actionscript 3.0

Hello there.
I was wondering if anybody could tell me the most accurate way of calling a function when an HD video hits a specific point.
I want to synchronise a video I have made with external events as accurately as possible and keep the quality as good as possible.
This would rule out exporting After effects markers as unless I am mistaken, to do this you have to export it as an FLV and loose a lot of quality.
I would like to call functions quite rapidly and have them "fire" exactly as the video hits the correct frame.
Are cue points the best way to go with what I am after and if so, is there any way I can assign them accurately?
I have tried doing it with the little scroller in the flash editor but it is rather cumbersome.
Thank you very much in advance for any possible replies,
Danny.

Ok, ive just realised that F4V is flashes container for HD video and so will retain good quality and also contain cue points. So that is great I think....
Unless anyone knows a better way of synchronising?
Thanks a lot,
Danny.