[warnergt]

While wrestling with the never ending audio/video sync problems with iMovie, I discovered the the frame counts don't add up. If you display the clips of a movie, it shows the size of each clip. If you click on a clip, it will highlight it, place it in the window at the start point and show the starting time. For a few clips, the starting time matches the sum of the clip sizes. Then, it starts to slip. After a few clips, the frame count will be off by one or two, and then more.

What's with that? How could the frame counts (all integer numbers) not add up correctly?

[ibookuser2]

It may have something to do with the fact that NTSC video is 29.97 frames per second. iMovie might calculate it as 30. That would result in a discrepancy in frame totals every now and then...

IIRC, Black and white TV was originally 30 FPS, but it dropped to 29.97 when the move to color took place. It's still easier to calculate stuff as 30 FPS though.