Recording Video and Audio at Same time with simultaneous sync

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Level 1

20 points

Recording Video and Audio at Same time with simultaneous sync

I want to record a keyboard performance into garageband and at the same time record the playing of that performance with my video camera. Then I want to create a movie using the music from garageband and the video from the camera. I was thinking that if I can sync the video and audio when I'm recording the session, then that part is taken care of. Or, maybe this is easier than I think it is?

Is there a way to do this so that I can use the garageband record performance and have it synced to the video on the camera?

I don't want to use the audio from the video camera because the performance that is captured in Garageband will be much better and I can do editing of the individual notes in GB.

In the end, I just want to make a movie and/or podcast of the performance.

I'm a newbie regarding this, but I did search the forums and couldn't find anything specific. Mostly it was about importing video into GB3 and then syncing new audio. I'll basically have audio and video from the same performance in two separate locations and I want to bring them together perfectly in Garageband.

Thanks for any help you can provide.

Powerbook G4 - DVI Mac OS X (10.4.9)

Posted on Jun 15, 2007 10:22 AM

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Answer 1

HangTime

Level 9

53,853 points

Jun 15, 2007 12:11 PM in response to alabamer

There's no reason to upgrade to GB3, however, you're in the GB3 forum. it's a good idea to post in the forum that supports the version of software you are using, and being here implies that version 3 is what you're using.

The video and audio files should not full out of sync since they are both digital

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Answer 2

alabamer Author

Level 1

20 points

Jul 19, 2007 9:19 AM in response to isteveus

That's really close to what I did, however, I didn't rely on the audio from the video as much as I should have. In the video I quickly ended the vocal of the last line of the Eagles song, but in the recorded audio overdub of the vocal, I was thinking I hadn't done that so I held it out too long. It's not too apparent with the quality of the video on Youtube and myspace, but if you saw the original, it would be. If I had more time, I'd fix the vocal there. Maybe in the future, but for now, I'm not too worried about it... It's a good first stab, though. Thanks for the comments, too. I appreciate it.

Powerbook G4 - DVI Mac OS X (10.4.9)

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Answer 3

Jun 15, 2007 12:11 PM in response to alabamer

The key is the ability to see the actual waveform of the event, which gives the wallclock time of the event. Thus it needs to be a sharp and clear event.

If you have to , before you start playing, clap your hands three times ( or even once ) while recording audio and video. The hand clap can become the sync point ( remember this is the clapper board .....)

GB2 shows the wave form. I have done 45 minute segments that were still in sync at the end with DV and audio files. Within the DV audio spec, the DV recorded audio can get slightly out of sync, but with a mixer recorded audio track once you have a single sync point, you should be good for 10 minutes.

The You Tube example is cut out of 45 minutes continuous video and audio, and it stayed synced.

Once I realized ( when you get your head around it ) how easy it was......well why ever use the DV audio?

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Answer 4

HangTime

Level 9

53,853 points

Jun 15, 2007 10:37 AM in response to alabamer

I think you'll have better luck reversing the process from what you think you want to do.

Work on the audio in GB to get it sounding the way you want, export it, and drop the exported video into iMovie. From there, have iMovie split it's Audio and VIdeo track into separate parts and then you can start by visually aligning your new audio track with the camera's. Then simply mute the camera's audio track.

I'd suggest getting more help with this in the iMovie forum, this is definitely the work flow you should follow, audio into iMovie, not video into GB.

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Answer 5

Jun 15, 2007 11:50 AM in response to HangTime

I do something similar with Logic/Final Cut, but the concept is simple. Think of the Hollywood Clapper board. It has a time, it is filmed and make a sound that is both recorded and filmed.

The trick with the audio and Video is to use first the audio waveform to identify a recognizable sound that was also captured by the video, it could be as simple as the first note, but should be able to be seen.

You can then note this time on Garageband for the audio event. Perhaps you want a 10 second lead in on video......make sure you have both the lead in recorded and filmed.

So, from the sync event, count back in seconds to the lead in point which is also where you want to cut the audio, this cut will be the start.

Now open the video on iMovie and find the SAME audio waveform event as your sync guide. In counting back be careful because Garageband uses seconds and I think iMovie uses frames. So you need to co-relate frames to seconds ( varies depending on what you shot the video in )

Now chop the video. Now import the audio from Garageband and the audio and sound should line up.

Make sure the audio event is easily seen in both the video and audio. Be as accurate as possible, 2 or three frames out can be noticed.

this is a sample with the mixer audio synced after to the video edit :

http://www.youtube.com/watch?v=4VLvwk_w9NU
You Tube resolution makes it hard to tell, but in the original it is frame accurate. I had to tweak the audio by 2 frames after the waveform sync.

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Answer 6

alabamer Author

Level 1

20 points

Jun 15, 2007 12:04 PM in response to Kevin Brown2

These are really good suggestions. Thank you very much.

I will work on these to see if I can get this to work. I actually don't have GB3, should I use that instead of GB2? I would have to upgrade.

Also, if you sync the beginning of both tracks, is there a chance that they'll get out of sync toward the end? I expect the recording of both GB and Video to be about 10 minutes. That's why I was thinking I need to sync them somehow.

Years ago I had a PC running cakewalk and synced via smpte to an analog multitrack recorder. You had to have those synced together in order for both medium's to stay together.

Thanks for any additional info.

Powerbook G4 - DVI Mac OS X (10.4.9)

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Answer 7

Jun 15, 2007 3:39 PM in response to Kevin Brown2

You don't need a visual sync event when your video camera records the sound, too. Actually, acoustic syncing or the two audio tracks is a lot more precise, since even a shift of one frame sounds like a reverb effect and suddenly vanishes when you're in sync.

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Answer 8

alabamer Author

Level 1

20 points

Jun 15, 2007 8:32 PM in response to HangTime

I'm sorry, I guess I posted here because I thought I'd be limited by GB2 and would HAVE TO upgrade. Since you're saying I don't really need to, I don't have to worry about going out and upgrading, which is a good thing.

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Answer 9

Jun 16, 2007 1:16 AM in response to Christoph Drösser

I guess I was a bit muddy. Of course you are lining up in an audio event, but often if the event is musical, it helps to use the visuals to find the actual audio event of interest. It is also useful to double check that the audio does indeed line up on the visual.

You only get the reverb effect if you are mixing the camera audio with an externally recorded audio mix. In this case I assume that would not be so.

To be honest if you have an audio recording from an external mixer, why would you use any of the DV audio, except to find the sync position?

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Answer 10

alabamer Author

Level 1

20 points

Jun 16, 2007 11:17 AM in response to Kevin Brown2

To be honest if you have an audio recording from an
external mixer, why would you use any of the DV
audio, except to find the sync position?

Could you clarify what you mean by this? I kind of know what you're getting at, but I was wondering if you could expand on it a bit so someone like me can better understand...

Actually, this is exactly why I posted on this topic. I was just wanting to ensure that my external audio could be sync'd to the video or vice-versa.

Thanks

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Answer 11

Jun 16, 2007 11:35 AM in response to alabamer

The DV audio is never very good. There is usually a cheap stereo mic embedded in the camera. BUT...... this audio is obviously shot in sync with the video, so the waveform of the DV audio is how we align the externally mixed audio ....... but once we have the external audio aligned via an event and a waveform, the we just cut out or mute the DV audio and ignore it.

Also have a look for a utility called timecode calculator, it can help aligning actual time with frames per second.

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Answer 12

Jun 16, 2007 12:32 PM in response to Kevin Brown2

Hi, Kevin,

The DV audio is never very good.

I think maybe you paint with too wide a brush.
It's true that your average consumer video camera is not going to have a great mike. However, I have gotten some very good and quite usable sound from pro video camera mikes, in the right setting.

WH

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Answer 13

alabamer Author

Level 1

20 points

Jun 16, 2007 12:36 PM in response to Windham Hillbilly

I would assume it depends on the usage or source you're recording.

When I record my piano with the DV audio, it's never going to get anywhere close to what it sounds like direct from a MIDI Sequencer instead.

If it's voice or something similar, the mic in my camera is excellent. Sometimes my wife is playing the camera back over the TV/Stereo while I'm in a different room and I would swear that I was hearing something that was real, not recorded.

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Answer 14

Jun 17, 2007 1:23 AM in response to Windham Hillbilly

I am painting HIS brush......he has a mixer and can record sound. This will ALWAYS be better than using even professional microphones.....how many mic's can you plug into a camera? You have an onboard mixer to optimize sound?

This is why we have mixer's....

Sure, it can be Just Good Enough, but mostly it is not.

Compare this:

http://www.youtube.com/watch?v=cf4M17CzZro

With this:

http://youtube.com/watch?v=4VLvwk_w9NU

First video has more cameras, a lot of effort.....but......live music sounds crap on DV quality cameras, and unless you mic up the band with as many mic's as a mixer, it will again not sound as good.

Second is a stereo mix taken off the mixer.

All live bands use a mixer for the house mix, so it should not be an issue to easily get even a stereo mix off the board.

You want to record voice? Fine, but live music....

Both video's are in the same venue.

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Answer 15

alabamer Author

Level 1

20 points

Jul 19, 2007 8:17 AM in response to alabamer

Okay. I got the video and audio all together. I told you I'd link to it when it was up.

http://www.youtube.com/watch?v=FxssYpUNJm8

There's also a copy of it at http://www.myspace.com/bonjimmy/

And as a quick side comment, even though I uploaded the same video to both YouTube and MySpace, the MySpace version is much better. YouTube must do something to the video after it's uploaded.

What I learned doing this project:

I recorded the video first (which gave me the sequencing of the piano performance) and then I dubbed the audio in later. However, there wasn't a good way to sync the video and the prerecorded piano, so there are some spots where the dubbed audio vocal isn't accurate to the video. I'm not sure what the pros do for this. I was hoping I'd remember how I sang for the video but when a couple weeks go by before re-doing the audio, it's about impossible. I tried, though.

I remember working with an old 4-track and smpte to a sequencer a long time ago. With the way it is now, it's pretty cool that you can record digitally and mix and match and everything falls together perfectly as long as you have a place to match the video and the audio. It's pretty cool.

What else???

Does anyone have suggestions that would have made it better? Also, if you have suggestions on my performance or whatever, I'd love comments, but you can do that on the linked page.

Thanks again for all your help. (The point of the video is because I'm thinking about getting back out there and doing some more playing... I'm looking for a band or something else interesting...)

Powerbook G4 - DVI Mac OS X (10.4.10)

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