Audio drifts when sent to ProTools

Dear Rduff8

I am going to send you a link to a version of code where we believe this is resolved.

Yours Sincerely

James.

Hi James,
The first frame of dialogue/production sound is 00:02:26:00, the first ~2.5 minutes will just be music and sfx that aren't in the sequence yet. Just in case that's what you mean when referring to the start time offset.

Can you clarify what you mean by the source essence when importing to Pro Tools? When we import into Pro Tools the bit rate is 24 I believe

Dear Rduff8

We can definitely see the issue in the last section of the project/sequence in ProTools, there is some re-timing, but this is not causing the offset for the start time. Looking at the import into ProTools we see the source essence (or some of it is 32 bit, can you confirm please.

Many thanks.

James

Hi again James,

I've attached the XML (zipped) and a zipped folder with screenshots of the error messages we were seeing in X2Pro after the AAF export completed (because we couldn't find how to produce a sidecar txt file through X2Pro). The conform rate messages do seem to suggest that the clips and project frame rates weren't the same, but we double checked multiple times and confirmed the original media clips and the project frame rates are both the same (23.98).

Our sync issue doesn't only apply to individual clips that are flagged in the error list, but the entire sequence. The whole sequence seems to be in sync with the video at the start, but over time the audio in the AAF drifts more and more out of sync with the video, until by the end of the project we're several frames out of sync. It doesn't seem like we can identify single clips or moments that are causing the issue.

We've also exported multiple XMLs from different FCP projects for the same film, and exported multiple AAFs with various different X2Pro settings, and we are seeing the exact same issue with all of them.

Please let us know if you have any ideas, thank you again for your help!

Thank you James let me send this off to the ProTools users and I’ll let you know the outcome

Dear Rduff8, 

If you can forward the XML and the sidecar text file that got created we can have a look,  essentially X2Pro does not support retiming or conforming and clips will be at the original speed in the AAF. 

To elaborate, X2Pro does not modify the audio file, we will however modify the duration of a clip to match. If I give you an exaggerated example, if a clip is at half speed in the FCPXML we will double the length of the clip in the timeline in the AAF but we will not alter the speed of the actual audio. The notes in the sidecar text file is essentially a list of the start times of these re-timed clips so that it can be supplied to who ever is doing the audio finishing that they will have to look at retiming's or conform rates for those clips.

A conformed clip is one that FCP X has automatically retimed because the frame rate of the clips was very close the the frame rate of the project. For example when a 23.98fps clip is used in a 25fps project, FCP X will play the clip at just over 104% speed. Fundamentally FCP X does not alert the user when it conforms clips.

This means that the project will look the same at a glance, with the start of the audio being the same but the end not. X2Pro should include all the audio for a conformed clip that was used in the FCP project, this should mean that you can retime the clip in Pro Tools to get the same as what you had in the FCP Project.  All conformed and retimed events should be listed in the sidecar text file.

X2Pro works this way because it was assumed that audio editing/adjustments/finishing would be done in the audio editing software (ProTools) rather than in FCPX.

Hope the above helps.

Yours Sincerely

James

Hello, trying to send a large project to sound. Used X2Pro to generate an AAF file from a Final Cut XML. When the AAF was imported into Pro Tools, the clips are organized on the timeline as they should be at first, but the audio drifts several frames out of sync with the video over the course of the film (with audio in Pro Tools ahead of the video). The video file is an Apple ProRes 422 Proxy exported from Final Cut, and the audio is in sync with video in the exported video file both in Pro Tools and on QuickTime. But in Pro Tools, the audio from the AAF drifts out of sync with the video.
In X2Pro, we see a number of errors that say "conform rates have not been applied" (but most don't show any corresponding timecode on the conversion report). This suggested to us that the frame rate of the FCPX project may have been different from the clips. However, we double checked and verified that the project frame rate and the frame rate of the raw footage are the same (23.98), and the Pro Tools session was set to that as well. We tried a few different AAF exports with different settings checked, but we're still seeing the same issue each time.