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AIFF drift in FCP 5.1.4?
Hello:
I have an 11 and a half minute long Quicktime motion graphic piece created in After Effects which I’m importing into FCP to add an AIFF audio track created by a sound designer. The Quicktime is 864×486, 30 fps (for Flash, not broadcast), animation codec. The sound designer created the audio in sync with an h.264 compressed version of the video.
I set up a sequence, 864×486, 30fps, animation codec, 44.1K Audio Rate and 24-bit depth and laid in the video Quicktime and AIFF audio track. The sync starts out okay, but by the end of the piece the AIFF audio is around 20 frames ahead of the video. A Quicktime that the sound designer created with the video and audio syncs correctly when that Quicktime audio is laid into the sequence.
I noticed that even though I set the audio bit depth of the sequence to 24-bit, it’s listed as 32-bit Floating point in the Aud Format browser column. Don’t know if that’s pertinent to this issue.
The strange thing is, if I bring the Quicktime video and AIFF audio track into After Effects, create a comp and drop the Quicktime video and AIFF audio into the comp, the AIFF audio stays in sync with the video.
One more observation. In FCP, the AIFF track duration is 00:11:32:09 when set to non-drop frame, 00:11:32:29 when set to drop frame. That same AIFF track, when imported into AE 6.5, shows a duration of 0:11:33:00. I don’t know if that’s pertinent or not either.
My strengths are 3D and motion graphics, not audio design. I can work around this problem by combining the audio and video in After Effects, but that’s not ideal. Any thoughts or suggestions? Is there a setting I’m missing somewhere?
Thank you.
Shawn Marshall
Portland, Oregon -
5 Replies
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The sequence settings that you have setup are not a native video format to FCP. It is no surprise that it won’t play it in sync as it’s not set up to handle odd size video very well and FCP chugs through the Animation codec. if I were you, I’d nest your sequence in a 720×486 anamorphic timeline with a more FCP friendly video codec. Distort your picture, render and watch. What kind of media drives are you playing this off of?
Jeremy
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Hi Jeremy:
Thanks for taking the time to reply.
If this was for video playback I’d do 720×486 anamporphic, 29.97fps, but it’s going to be turned into a Flash video.
I’ve used the animation codec at 864×486 many times without having any problems playing it back off a single, fast, Firewire drive. I trust that codec more than 8 or 10 bit uncompressed since I see luminance shifts in those sometimes. I’m not attempting to play it through my Io system; I just want to marry the video to the audio and export the result as a Quicktime.
The problem isn’t dropped frames or stuttering playback, it’s that the audio sync gets progressively more off the further you get into the piece. And if I scrub to the end of the sequence the audio doesn’t jump back into sync; it’s off by the same amount as if I’d been playing it at normal speed from the beginning.
I think there’s some weird sample rate thing going on between the AIFF and FCP, but I don’t know what.
Shawn Marshall
Marshall Arts Motion Graphics -
[Shawn Marshall] ” I trust that codec more than 8 or 10 bit uncompressed since I see luminance shifts in those sometimes.”
That’s coming from AE. It’s the ole YUV to RGB to YUV deal.
[Shawn Marshall] “I think there’s some weird sample rate thing going on between the AIFF and FCP, but I don’t know what. “
Could be, hard to know without looking at what you have.
[Shawn Marshall] “nd if I scrub to the end of the sequence the audio doesn’t jump back into sync; it’s off by the same amount as if I’d been playing it at normal speed from the beginning.
“Got ya. I misunderstood. From you other post you had mentioned the lengths. In drop frame, it is a certain length and in non drop it is one frame off from the AE length (which probably means it’s the same length, you are just counting the last frame of the AE comp when there really is nothing there). So why not use the non drop? Even if you play the non drop, which is basically the same length as the QT movie, it still moves out of sync?
What happens if you change the timeline sample rate to 48k?
Jeremy
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Hi:
Thanks again for your reply.
Changing the sequence to 48K didn’t affect the timing issues. Changing the duration designation from non-drop to drop-frame or frames doesn’t change the timing in the sequence; it stays the same length (and drifting sync) no matter how the time is counted.
Shawn Marshall
Marshall Arts Motion Graphics -
Sheesh, misunderstood again.
I am at a loss as to why this could be happening within FCP.
Why not just export it out of AE? Why is that not ideal you say?
Jeremy
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