Trying to sync video and audio from 2 completely different sources...

[ThaKarra]

Hi all,

Apologies if this is the wrong section of the forum to post this.

I'm super new to video conversion/editing etc. So please bare with me if something I'm doing is completely wrong, I'm still trying to learn.

Okay,

So basically I have 2 videos of the exact same episode. One was recorded by me ages ago off the TV. It has amazing video quality, however the audio is very poor and hard to hear. - The other is something I found online, but its the complete opposite; the picture quality is horrible but the audio is perfect.

I'm trying to do a restoration/upscale on this particular episode for my archives. My goal is to take the audio from the file I found online and try to sync it to the video I originally recorded off the TV. However I'm experiencing great difficulty.

Both files are 23.976 frames per second.

When I import them into my editing software and line them up, my recording is overall around 2-minutes longer than the one I found online, despite them being the exact same thing.

When I line them up frame for frame and try to sync them.. the start of the clip is perfect. I can get through the first few minutes perfectly. Its around 10 minute point where it slightly starts falling out of sync. By the time you get to the end of the episode, the whole thing is out of sync by about 30-40 seconds.

I'm only guessing but I assume this is happening because despite both being 23.976 there are more overall duplicated frames in my recording which is gradually pushing it out of sync. - Hence why my recording is about 2 minutes longer.

Is there an easy way to fix this or accomplish what I'm trying to do? Or is it just far more trouble than its worth? Are there any tools, scripts, plugins etc.. That can help assist me with this kind of task?

[Budman1]

It may be very difficult. Let's say your TV video was edited for the time allotted and 2 parts cut from it. Now imagine the online version was also edited but not in the same places. Parts from the first video would have to be trimmed out to match the online video and parts from online video trimmed to match the TV Version.

If you are sure the words are always there throughout the whole move, you might try ffmpeg Atempo filter to stretch/compact the audio. If the video is long enough, (Atemppo=desired length / Audio length) any pitch changes would be very slight.

[Alwyn]

When I import them into my editing software and line them up, my recording is overall around 2-minutes longer than the one I found online, despite them being the exact same thing.

Some editing software can easily stretch audio and or video to match/resync. What program are you using?

[ProWo]

Extract both audio tracks and convert them to PCM (wav).
Then load both tracks into Audacity (the bad track, synchronized with the good video on top and the good audio track below) and then adjust the lower track to the upper track (move and cut).
When the lower track fits, delete the upper track and save the modified new track.
You can then re-encode it as desired and mux it to the video.