A possible solution to audio and video synchronization problem

nealeh wrote on 1/14/2009, 9:28 AM

Rescue Your Video Tapes!

Like many I’ve experienced the problem of audio and video not being synchronized.

I’ve found two solutions to my problem that may or may not be helpful to others.

The problem seems to me to be two-fold:

* The Magix proprietary encoder
* Movies on DVD 7 [hereafter abbreviated to MoD7] software.

When you start up MoD7 and select ‘Recording -> Analog Video’ the Video recording screen pops up. Item 3 ‘Recording Quality’ is where I have found two solutions that work for me (so far!).

By default the selection box will say ‘MXV: DVD Quality’. This sets MoD7 to use the Magix proprietary encoder. Click ‘Configuration’ and you get a screen in two halves. The top is Video and the bottom is Audio. At the bottom right there is a checkbox ‘Audio sample rate drift correction’. Turn it off – job done (for me).

As far as I can make out having this checkbox on activates a feature in MoD7 where the software is somehow (fuzzy logic perhaps) continually trying to match the audio with the video. I think the sync problem happens because the software gets it wrong!

The other solution that worked for me was to change the Recording quality selection box from ‘MXV: DVD Quality’ to ‘MPEG: DVD’. This bypasses the Magix encoder altogether and uses a generic MPEG encoder (Ligos I think).

Good luck!

--
Neale
Insanity is hereditary. You get it from your children

Comments

GreySquirrel wrote on 3/31/2009, 4:12 AM

I agree that the logic which is trying to correct for audio drift is probably faulty. I have tried it with a very old mono VCR as the analogue source, and the result was fine with a 'correction' calculated as 48000.871159. Editing this factor back to 0, which activates a recalculation, and reverting to a newer sterio VCR it calculated 47146.802784, but the result was tens of seconds out of phase. When I tried MPEG:DVD, it seemed to use too many resources with CPU nearly up to 100%.

What worked for me was to use the standard MXV:DVD, but edit the correction factor to 48000.

Also helps to have as little else running as possible. I was using less than 50% CPU, all of the time.

jednick wrote on 7/19/2009, 7:35 PM

GreySquirrel & Nealeh:

Unchecking the "Audio sample rate drift correction" and staying on MXV:DVD solved the synchro problem for me. When I unchecked the box AND switched to MPEG:DVD, the sound was OK but the video quality was very bad.

Thanks to both of you for sharing this; I never would have figured it out otherwise.

Jed

markjl wrote on 3/29/2010, 1:28 PM

I'm still confused really. Having just reinstalled Video Deluxe, it seems that the first recording is used to automatically calculate the drift. But the second recording is no better. I have a difference of 25 frames between video and sound. And I'm not even sure that this remains the same throughout. What is drift? Why does it occur and why am I only only experiencing this now after many hours recording?

It cant be related to performance in my case ? since the cpu runs at under 10% load.

I tried clearing the manual drift figure. Magix recalculated on the next recording but no better ...

nealeh wrote on 3/30/2010, 9:19 AM

I'm not familiar with Video Deleuxe, but if you have the option to turn off 'audio sample rate drift correction' do so.

Cheers,
--
Neale
Insanity is hereditary, you get it from your children

markjl wrote on 11/27/2011, 9:39 AM

Hello. I'm getting the problem of drift again on a different machine. Neither the second recording, nor deleting the correction figure enable proper recording.

Could this be a question of computer speed? I have the problem on two machines: one an AMD Athlon 7450 @ 2.4 GHz and 3 Gb RAM, the other an AMD Sempron 3400+ @ 1.8 Ghz and 2 Gb RAM both using Magix Films Sur DVD 8.

Lost, thanks