need help with a sync problem at DVinfo.net

Bruce Watson · July 28th, 2011, 02:05 PM

I got handed some footage from an iPhone 4. The footage is actually decent for what it is, and the rough edit is good enough that the client wants to move forward. The final target is video for YouTube, so nothing terribly fancy.

The problem is that the video leads the audio. In some places by a lot. It looks like the sync is off by about two seconds for every sixty of run time. Since the original footage is in files that are several minutes long each, this is a problem I'll have to fix. Thankfully there's no faces in the video, so I don't have to be really accurate at the lip-sync level. But a couple of seconds between an action and a sound is way noticeable.

What I need to learn how to do is to cut the audio separately from the video in Premiere Pro CS5, and how to slide the audio relative to the video to make them line up in the individual short clips I'll cut from the original footage.

So... how do I separate the audio and video? and how do I slide the audio back and forth to line it back up with the audio? Once lined up, how do I re-link the video and audio so I can make subclips? Can I do that in the Source Monitor or do I have to do this on the main timeline?

Clearly I'm a total newbie at this kind of editing; any pointers to tutorials (I've searched and found nothing that pertains, but I'm sure they are out there somewhere) or instructions are gratefully received.

Bart Walczak · July 29th, 2011, 04:48 AM

First make sure it is really a problem with footage, not with Quicktime and Premiere and it's audio conforming. Play it out on VLC player or some third-party tool. We've had our own share of issues with out-of-sync audio that was essentially only a problem with Quicktime, not with the footage itself.

If it is indeed the issue with footage, the only workaround that I can see is dropping the clips on the timeline and syncing it manually. You can unlink the audio and video by right-clicking on the clip and selecting "unlink", alt-clicking on video or audio to select only video or audio portion of the clip without unlinking, and if you have a lot of such work to do you can define a keyboard shortcut for unlink action in keyboard settings.

Hope this helps.

Bill Pryor · August 6th, 2011, 09:30 AM

I agree. Play the clip on something else to make sure it really is out of sync. I have to make WMVs for a client, and while my timeline is in sync and my QT export is in sync, the WMV always plays out of sync. Finally checked it on a PC and it was in perfect sync. WMVs just play out of sync on a Mac, apparently. It could be something similar with your footage.

July 28th, 2011, 02:05 PM	#1
Bruce Watson Major Player Join Date: Mar 2010 Location: Raleigh, NC, USA Posts: 710	need help with a sync problem I got handed some footage from an iPhone 4. The footage is actually decent for what it is, and the rough edit is good enough that the client wants to move forward. The final target is video for YouTube, so nothing terribly fancy. The problem is that the video leads the audio. In some places by a lot. It looks like the sync is off by about two seconds for every sixty of run time. Since the original footage is in files that are several minutes long each, this is a problem I'll have to fix. Thankfully there's no faces in the video, so I don't have to be really accurate at the lip-sync level. But a couple of seconds between an action and a sound is way noticeable. What I need to learn how to do is to cut the audio separately from the video in Premiere Pro CS5, and how to slide the audio relative to the video to make them line up in the individual short clips I'll cut from the original footage. So... how do I separate the audio and video? and how do I slide the audio back and forth to line it back up with the audio? Once lined up, how do I re-link the video and audio so I can make subclips? Can I do that in the Source Monitor or do I have to do this on the main timeline? Clearly I'm a total newbie at this kind of editing; any pointers to tutorials (I've searched and found nothing that pertains, but I'm sure they are out there somewhere) or instructions are gratefully received.

July 29th, 2011, 04:48 AM	#2
Bart Walczak Major Player Join Date: Apr 2006 Location: Warsaw/Poland Posts: 716	Re: need help with a sync problem First make sure it is really a problem with footage, not with Quicktime and Premiere and it's audio conforming. Play it out on VLC player or some third-party tool. We've had our own share of issues with out-of-sync audio that was essentially only a problem with Quicktime, not with the footage itself. If it is indeed the issue with footage, the only workaround that I can see is dropping the clips on the timeline and syncing it manually. You can unlink the audio and video by right-clicking on the clip and selecting "unlink", alt-clicking on video or audio to select only video or audio portion of the clip without unlinking, and if you have a lot of such work to do you can define a keyboard shortcut for unlink action in keyboard settings. Hope this helps. __________________ Creative Impatience - The Solace of Simple Solutions. A few useful plugins for Adobe users, and my remarks on the tools and the craft in general.

August 6th, 2011, 09:30 AM	#3
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Re: need help with a sync problem I agree. Play the clip on something else to make sure it really is out of sync. I have to make WMVs for a client, and while my timeline is in sync and my QT export is in sync, the WMV always plays out of sync. Finally checked it on a PC and it was in perfect sync. WMVs just play out of sync on a Mac, apparently. It could be something similar with your footage.