AI 7.1 Audio Sync Issue

Hi!

One more problem with AI Version 7.1: While playing videoclips, the audio is going out of sync (about 2 sec for about 10 minutes video length). Are there any settings according to such problems? The files are Quicktime with AiM Codec and PCM Audio with 16bits/48khz and stereo audio track. We have both tested 25 and 30 fps and different resolutions. In Quicktime, the files are working fine.

thanks
Josef

are the video and audio going out of sysnc or are they staying in sync but just playing back at the wrong speed?

our preference for encoding AiM files with audio is to use 44.1 khz uncompressed stereo as the type.

Audio and video are going out of sync. PCM is uncompressen format, it means pulse code modulation. In our case, its 48 khz.

Hi

Please try the following:

In the stage patch or anywhere in your project, right click the background of a patch window and choose insert module/audio/Sync offset.  This module lets you adjust the overall system sync by an offset in seconds (or fractions of a second like 0.5 = half a second etc..).

If you make this module a little larger by dragging the bottom down and the side out a bit then right click the background of the module and select 'reset skin'.  You should now see another parameter which is called Continuous Sync.  If you set this to 1.0 (rather then the default of 0.0).  Then the system will drop frames in favour of maintaining synchronisation with audio.  The default is to always try not to drop frames, which may result in the audio drifting out of sync over time.

Hope this helps, please let us know if you need further assistance on this matter.

Thanks & best regards

Thanks! With continous sync, all is working fine. Is there any posibility to detect frame loss? Another question: Should Nvidia Quadro K4000 work with Ai? We have some troubles with the AMD cards in conjunction with different HDMI Repeaters and signal loss. At the moment, i´m working with old Nvidia GTX 260 because of this problem.
Thank you and best regards
Josef Hackl

All Nvidia Cards purchased after ~2009 should work well with Ai.  Obviously the newer the better.  We advise using the latest drivers from the NVidia website.

The frame loss resulting from maintaining sync with audio will only be single frame and very occasionally, you probably won't see the difference visually.  Watch it for a bit and if it looks fine then I would assume its not worth worrying about.  The reason we default to the other mode of operation is that a lot of our customers are triggering video content without audio to accompany an Audio Department in a show environment.  Sync is then usually achieved via a timecode feed in this scenario.

Thanks and best regards

Ok, fine!!! Thank you very much!

Josef Hackl

Hi!
One more problem according to the sync offset module: It is only working with the miami license! Is there any solution according this problem? We need a very quick solution!! Our license is bondi.
Thanks
Josef

Any news to my question?

Thanks,
Josef

Hi Josef

We will try to update this and make the audio sync offset module available to all licence levels in the next build update, that should appear in the next few days.

Thanks and sorry for the delay getting back to you on this, we have all been out of the office on lots of jobs.

Best regards