Latest post Tue, Jul 1 2008 6:55 PM by linus210. 9 replies.
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  • Tue, Jul 1 2008 2:42 AM

    • linus210
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    24p audio sync issues

    OK, so I just started a job that was shot at 24 frames a second using the RED camera.  I am using a online house to transcode the files to standard DV QT's that I have then used metacheater to create the ALE file.  Everything imported great into my 24p NTSC project, except for the audio, which is incredibly out of sync.  And at the end of the clip the audio starts looping on itself with a distinct digital blip that starts the looping.  I tried importing the quicktimes into a 30i project and the audio was just fine, and also, the quicktimes themselves are fine...so obviously it is something happening on the import of th qts in the 24p, or the 23.976 project.  Does ANYONE have any idea what could be happening?  I have tried all the different import settings in the audio tab and it is still out of sync and looping.

     

    Thanks in advance for any advice...

     

    Avid Media Composer PC Version 2.5 [view my complete system specs]
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  • Tue, Jul 1 2008 2:53 PM In reply to

    Re: 24p audio sync issues

    You have to ask what is the sample rate in which the audio was recorded. Audio might have been recorded at 48.048 kHz (vs 48 kHz flat).

     

    Intel E6600, Windows XP SP2, EVGA 8800 GT, 4GB RAM, Creative X-Fi. [view my complete system specs]
  • Tue, Jul 1 2008 3:14 PM In reply to

    • linus210
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    Re: 24p audio sync issues

    And if it was recorded at 48.048, how do I adjust that on my import to have it come in correctly?

    Avid Media Composer PC Version 2.5 [view my complete system specs]
  • Tue, Jul 1 2008 3:22 PM In reply to

    • linus210
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    Re: 24p audio sync issues

    and just for the record, checking this one clip, the audio is a full six seconds ahead of picture.

    Avid Media Composer PC Version 2.5 [view my complete system specs]
  • Tue, Jul 1 2008 3:22 PM In reply to

    Re: 24p audio sync issues

    More info here.

     

    Intel E6600, Windows XP SP2, EVGA 8800 GT, 4GB RAM, Creative X-Fi. [view my complete system specs]
  • Tue, Jul 1 2008 5:09 PM In reply to

    • linus210
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    Re: 24p audio sync issues

    Thanks for the link...unfortunately that doesn't seem to be working either.  Any other ideas?

    Avid Media Composer PC Version 2.5 [view my complete system specs]
  • Tue, Jul 1 2008 5:20 PM In reply to

    Re: 24p audio sync issues

    Well right now, it may be related to sample rates and fps. It may not. Hard to tell. Can you provide more technical info on both the RED/QT files and the audio files (frame rate, codec, sample rate, etc). Your system specs would be of great benefit also.

     

     

    Intel E6600, Windows XP SP2, EVGA 8800 GT, 4GB RAM, Creative X-Fi. [view my complete system specs]
  • Tue, Jul 1 2008 6:25 PM In reply to

    • linus210
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    Re: 24p audio sync issues

     

    Well, the RED files were converted at an online house to standard DV-DVC Pro NTSC.  They are at 24 fps.  The audio is an "Integer (Big Endian) codec.  I used metacheater to then create the ALE file, then did a batch import on the files.  I think it has something to do with Metacheater, as if i import them straight from the file itself, and not use metacheater, the sync is fine.  The only issue there is that the TC from the RED quicktime is non existent as it defaults to one hour.  I am assuming the audio was captured at 48k.  My system specs are Avid Media Composer v.2.5.2 on a HP xw8000.  Thanks again for your info.

     

     

     

     

    Avid Media Composer PC Version 2.5 [view my complete system specs]
  • Tue, Jul 1 2008 6:34 PM In reply to

    Re: 24p audio sync issues

    Open the file in QT and press Control + I. The info window will give you details about sample rate and etc.

    Do the same for the QT files. Are you sure those QT files are 24p and not 23.976p?

    Was the camera running at 24 or 23.976?

     

    Intel E6600, Windows XP SP2, EVGA 8800 GT, 4GB RAM, Creative X-Fi. [view my complete system specs]
  • Tue, Jul 1 2008 6:55 PM In reply to

    • linus210
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    Re: 24p audio sync issues

    FPS is 24, and the audio format is 48

    Avid Media Composer PC Version 2.5 [view my complete system specs]
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