Trying to sync audio to video. What would the best way be.

[paul92]

Hi all

not sure if this must go in the editing section, or restoration, so trying in both.

I have come across the Live Aid original Live Aid broadcast https://archive.org/details/live-aid-1985-full-bbc-broadcast, but is in mono, and the audio is crap. but the picture is okay for a concert that is 40 years old next year.

and also have the track by track stereo FLAC version, which seems to match the broadcast version, and decided that I would remove the mono audio, and replace it with the stereo version. I have synched music videos before, but this is something else. After rejoining the flac files, and synching them up in Adobe Premier to the video, it's only a matter of time before the audio goes out of sync, which obviously means either there are a few seconds missing, or there is a FPS/speed problem, in which either the audio is faster than the picture, but maybe someone here will be able to point me in the right direction.

What would be the easiest way be to synch the audio to the video. I was using the mono audio is a guideline to try to match by the audio wavelength, but I seem to be off by a few milliseconds, and it's impossible to drag to get a 100% fit.

I was thinking about breaking the video up into small videos, and correcting the audio video by video before joining them up again.

If there were any AI tools that could detect similarities between the stereo and Mono tracks, and sync them, that would be amazing.

Looking forward to feedback.

Thanks

[ProWo]

Hi all

not sure if this must go in the editing section, or restoration, so trying in both.

I have come across the Live Aid original Live Aid broadcast https://archive.org/details/live-aid-1985-full-bbc-broadcast, but is in mono, and the audio is crap. but the picture is okay for a concert that is 40 years old next year.

and also have the track by track stereo FLAC version, which seems to match the broadcast version, and decided that I would remove the mono audio, and replace it with the stereo version. I have synched music videos before, but this is something else. After rejoining the flac files, and synching them up in Adobe Premier to the video, it's only a matter of time before the audio goes out of sync, which obviously means either there are a few seconds missing, or there is a FPS/speed problem, in which either the audio is faster than the picture, but maybe someone here will be able to point me in the right direction.

What would be the easiest way be to synch the audio to the video. I was using the mono audio is a guideline to try to match by the audio wavelength, but I seem to be off by a few milliseconds, and it's impossible to drag to get a 100% fit.

I was thinking about breaking the video up into small videos, and correcting the audio video by video before joining them up again.

If there were any AI tools that could detect similarities between the stereo and Mono tracks, and sync them, that would be amazing.

Looking forward to feedback.

Thanks

1) at time a, the mono track and the flac track start with the same sound (a must be the same for both).
2) the monotrack ends at time b.
3) at time c the flac track ends with exactly the same sound as the mono track.
Cut away any excess at the beginning and end.
b-a=duration of the mono tracks
c-a=duration of the flac track.
Adjust the duration of the flac track to that of the mono track without changing the pitch.
You don't even notice a few milliseconds difference.
For the calculations, convert all times to seconds.
You can view and edit both tracks simultaneously in audacity.

[paul92]

The stereo track has been divided into tracks, but if reassembled, it's the full concert.

The stereo track of the broadcast is 44100hz, whereas the audio from the video is 48000hz. The imported stereo audio gradually goes out of sync with the video. I tried to increase the sample rate of the stereo audio to match the mono audio broadcast, but then is too fast.

[Alwyn]

Does Premiere have an audio stretch feature?