How to sync seperate Audio and Video

I was quite surprised that my search didn’t find an answer here.

I said a few days back I was ready to record a new song before end of year but, this time I want to record the audio seperate from the video.

What problem am I likely to come across, best practices when doing so.?

Would it be a good idea to still record sound in the video and sync to the audio but mute at render. Thank you much, hope to have it done in a few days or less.

R

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I can answer for using Reaper for audio and Shotcut for video. I do most of the audio editing in reaper (obviously), applying effects, tweaking volume here and there, but I leave any cuts until after I’ve exported it as an mp3 . I then import the video and the mp3 into shotcut. The video appears on the shotcut timeline as a series of thumbnails with the soundtrack underneath, which even when muted, is represented as a waveform. The mp3 is on a separate track also represented as a waveform. It’s possible then, especially if you’ve clicked your fingers or clapped your hands at the very start, to line up the two tracks by eye (there is a way to automate this, which I found by accident but I’m not sure I could replicate it). a bit of watching and listening to fine tune the sync and you’re away, able to make cuts and fade transitions to your heart’s content!
Reaper is allegedly able to edit video, but I’ve tried it and I wasn’t happy with the rendering, apart from the fact that you can only see the soundtrack you’re editing, not the video! A separate video editor gives a far better result.

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Most of the time I keep it simple with play-through recording both at the same time. When I have to sync audio and separate video I use iMovie on my mac. Heck, I use iMovie on 95% of my videos because it allows some fine tuning of the audio as well as video filters, etc.

You basically just need clear audio and visual starting points/cues (doesn’t have to be as obvious as a handclap). A thump on the guitar or other should suffice.

A time that I had to sync audio and video (that comes quickly to mind) was when I used an additional video source: Touch of J.J.
I did a subtle arm lift when the kick drum started the audio. There was also a clear tick-in.

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If I am taking this approach I’ll record audio in Reaper passing that to combine with video and audio in OBS. I then import the video back into Reaper, align the wave forms so all is in sync. Mute the video track in Reaper, mix, master the audio. Then render as video output. :sunglasses:

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BTW this is what the clapper board is for in movies, you can clap or whatever to set a definitive point for syncing

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Hello Rachel,

I suppose everyone has different methods. Here’s mine that has worked very well for some time.

I use Reaper and OBS. Nothing else.
Setup, one time only - Route audio from Reaper to OBS, using Rearoute.

Hit Record in both OBS and Reaper. I just have a split window setup.
Once done, import OBS video into Reaper. So you’ve now got 2 tracks in Reaper.

  1. The OBS video ( with embedded audio)
  2. Reaper audio track
  3. ( You may also have a track containing a Backing Track if you’re using one).

Synch up the video to the Reaper audio. Remember to turn the audio down in the video, rather than mute it; otherwise you won’t see any video. You can utilise the actual waveforms though to assist in synch.
The benefit here is you have the full capabilities of Reaper’a audio processing to create whatever sound, effects etc you desire, post recording.
Finally, hit Render, usually to mp4. Upload to Youtube etc.
Once setup, its a very straightforward process, and works very well.

Note: Reaper’s video capabilities are much more capable than one may think. No real need for any additional video processing software, as there are many built-in processing effects etc that are sufficient for the purpose.

Cheers, Shane

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It’s important that the video has at least a minimal audio track. I use my camera with it’s built-in speaker. It is poor quality, but it gives me enough audio to be used to match with my separate audio track.

A lot video editing programs have built-in sync features. I use Adobe Premiere Pro. I believe FinalCut Pro on the Mac also has this feature.

I have also used a standalone product call Pluraleyes. It got bought by another company and I don’t know if it is still offered.

You can also do it manually by lining up the audio and video tracks in your video editor. As mentioned above having a clap or other loud sound at the beginning really helps identify where the two tracks match.

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Absolutely, Rachel, this is a must. Many ways to go about this as per the various suggestions made already. The details would depend on the gear you are using to record the video and audio.

In addition to all the tips provided, I would do the following when syncing audio recorded in the DAW with the video audio.

I would first line up using the waveforms, syncing on that first clap or tap, a short, sharp sound. Then I pan the audio sources, hard left and right, and adjust the levels so both sources are at the same levels. Once you have done this then you can mute one and hear the other in one ear. When you unmute both then you hear both together in the centre, without any delay between the two. I found this was a good test and could make any fine adjustment.

Remember to turn any snap to grid function off in your DAW.

The other option, again depending on gear and how you want to record audio, is to take a little time in the setup before recording and not have to do any post processing. I follow this approach now, using OBS and a webcam on a PC. OBS has the capability to apply the same VST plug-ins I use in my DAW on an audio track. It took some experimentation to figure it all out but now I can setup quickly and don’t spend any time post-processing the audio.

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Thank you all for your input, I’ve read everyone and a few more than lol. I understand now how this is done.

See you on the otherside soon :slight_smile:

Rachel.

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That’s a brilliant idea. Thanks for sharing. I will give that a try.

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Do not go into the light, you have more music to play and life to live. LOL

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