Audio Sync Prob because of Sampling Rate (I think) at DVinfo.net

Go Back   DV Info Net > Windows / PC Post Production Solutions > Non-Linear Editing on the PC

Non-Linear Editing on the PC
Discussing the editing of all formats with Matrox, Pinnacle and more.


Reply
 
Thread Tools Search this Thread
Old January 13th, 2003, 04:08 AM   #1
Major Player
 
Join Date: Sep 2002
Location: Cupertino, California, USA
Posts: 301
Audio Sync Prob because of Sampling Rate (I think)

Hi,
I am currently editing a video where the sound was recorded separately from the video. So now I am editing the video and trying to sync up the sound with the video. Here is my problem: the sound will be synced up it the beginning, but then at the end of the video (45 minutes later) the audio is way off. I figured this was a sampling rate problem. I think my audio (which is off a burnt CD) is 44kHz and my video is 48kHz. I don't know how to fix this problem. I thought about setting the speed of the audio to like 97% to fix it but I don't know if that will really work. Does anyone know my problem and any software/ways to fix it? Thanks so much!
__________________
Scott Silverman
Shining Star Digital Video Productions
Bay Area, CA
Scott Silverman is offline   Reply With Quote
Old January 13th, 2003, 05:38 AM   #2
Warden
 
Join Date: Mar 2002
Location: Clearwater, FL
Posts: 8,267
What was the audio originally recorded to? Was it recorded to audio tape, DAT, MD etc.? It's going to make a difference in getting this to work.

Jeff
Jeff Donald is offline   Reply With Quote
Old January 13th, 2003, 02:50 PM   #3
Major Player
 
Join Date: Sep 2002
Location: Cupertino, California, USA
Posts: 301
I actually don't know. I did the video recording and another guy handled the audio. I believe it was recorded to a PC or mac. But I am not 100% sure. Thanks.
__________________
Scott Silverman
Shining Star Digital Video Productions
Bay Area, CA
Scott Silverman is offline   Reply With Quote
Old January 13th, 2003, 03:21 PM   #4
Warden
 
Join Date: Mar 2002
Location: Clearwater, FL
Posts: 8,267
If it was done to an audio tape forget it. It will never sync perfectly. If it is an audio CD it will be 44.1KHz and your editing at 48KHz. Import the audio into a program like QuickTime (PC version will work or PC equivlent), then export to what ever audio format your NLE uses and change the rate to 48KHz before you export. Export function will allow you to adjust bit rate, freq. file format etc.

Jeff
Jeff Donald is offline   Reply With Quote
Old January 13th, 2003, 04:15 PM   #5
RED Code Chef
 
Join Date: Oct 2001
Location: Holland
Posts: 12,514
I don't think the 48 kHz vs. 44.1 kHz is the problem. I think the
problem originated in different timing chips whilst recording, isn't
this why the big productions use synced timecode for everything?

Now I know there are applications out there that will make your
audio track exactly as long as your video and it should match
then. Unfortunately I forgot which one. You might try and see
whether Virtualdub at www.virtualdub.com might pull
it off.

Good luck!
__________________

Rob Lohman, visuar@iname.com
DV Info Wrangler & RED Code Chef

Join the DV Challenge | Lady X

Search DVinfo.net for quick answers | Buy from the best: DVinfo.net sponsors
Rob Lohman is offline   Reply With Quote
Old January 13th, 2003, 04:21 PM   #6
Major Player
 
Join Date: Nov 2002
Location: Toronto, Canada
Posts: 484
Audio Sync Prob because of Sampling Rate (I think)

I believe Cool Edit 2000 will allow you to set a duration without changing pitch. I've played with the function but never with this purpose in mind.
David Hurdon is offline   Reply With Quote
Old January 13th, 2003, 05:16 PM   #7
Warden
 
Join Date: Mar 2002
Location: Clearwater, FL
Posts: 8,267
If the source was digital (HD, DAT, MD etc.) you should be within a second or less at the end. Typically when I do this for a client from a digital source I'm zero to may be six frames off. I hide the errors at the end with lots of cut aways so it harder to notice.

Locking the timecode assures accuracy to at least 1 field.

Jeff
Jeff Donald is offline   Reply With Quote
Old January 13th, 2003, 08:35 PM   #8
Major Player
 
Join Date: Sep 2002
Location: Cupertino, California, USA
Posts: 301
I would like to do what Jeff originally mentioned. Importing it into Quicktime and changing the sampling rate and then exporting. Now how would I go about doing this? I have Quicktime on my PC but I don't know how to save and export files. (I didn't even know it was possible.)

PS - I am editing on Premiere 6

Thanks!
__________________
Scott Silverman
Shining Star Digital Video Productions
Bay Area, CA
Scott Silverman is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Windows / PC Post Production Solutions > Non-Linear Editing on the PC

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 02:16 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network