Quicktime and HD Videos

I'm trying to play HD xdcam 422 1080i files which are about 8gb, which I got transferred to my external hard drive from another MAC. However, when I try to open them in quicktime, all I get is audio, no video. I downloaded VLC, and I can't even get the audio, it's just telling me the format is not accessible. Any idea why these won't play? The first time I clicked the video to open in quicktime, it took me to a 3rd party apple page. However, it doesn't do that anymore. Help is greatly appreciated.

Any ideas?