iphoto 11 video files not playing

At some point recently my older video clips stopped functioning in iPhoto11. The files appear to be there - in the info box it shows that they are much larger than still images, but it also says that they are RAW filetype. When I double click on them, a warning triangle appears with an exclamation point.

I've tried exporting them so I could play/convert them with another program, to no avail.

Ideas?