Synching Video and Audio

lennymac

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Hi All - I'm in the middle of my dissertation for Uni - but once finished I am hoping to start posting videos to youtube. I have a pretty ropey video camera and also the video camera on the iPhone 5 - however the sound is not great on either. I have a home studio set up with some half decent condenser mics, and I also have a zoom H2N which I can use for capturing sound.
My question is - how easy is it to replace the sound of a video and synch it? What software do you use for this? I have Windows Live Movie Maker on my laptop, I also have imovie on the iphone - can I do it with this? Thanks in advance for your advice.

Ross
 
If you have a good XLRmic, iRig make a device to use that on an iphone/pad, £24 ot 'tinternet, £35 apple store.
iRig PRE, runds off a 9v battery and will provide phantom power to the mike. This will allow you to at least get decent sound on the iphone.
Never tried it so cannot comment on how good it is.
See: http://www.ikmultimedia.com/products/irigpre/
h
 
But it plugs into the headphone out right? That means line noise, and it'll sound a bit crap. He already has a Zoom h2n he doesn't want to take a step down. I don't know how to use Windows Movie Maker, but generally you'd mute the audio in the video you imported, and replace it with the audio track from the Zoom. The best way to learn how to sync it is kinda trial and error of what works for you.
 
I extract the audio from the video file then use Audacity to line up the audio from the video file and the audio that has been separately recorded. You need to make sure that the "separate" audio track is exactly the same length as that from the video which will involve some cutting and/or splicing in silence at the beginning and end. Once you've done that you can delete the "video" audio track from Audacity and export the modified audio track as *.wav, then do a Plainsong describes above.
 
I extract the audio from the video file then use Audacity to line up the audio from the video file and the audio that has been separately recorded. You need to make sure that the "separate" audio track is exactly the same length as that from the video which will involve some cutting and/or splicing in silence at the beginning and end. Once you've done that you can delete the "video" audio track from Audacity and export the modified audio track as *.wav, then do a Plainsong describes above.

:agree: - sort of :)

What Geoff describes is pretty much what I do, but I do it right in the video editor I use (Corel Pro X5 - and that's not an endorsement as there are some things I don't like about it).

Anyway, one thing they did get right in Corel is handling audio. Usually when I record with a separate audio track I am using my Flip HD for video and using a microphone and/or pickups through a USB audio interface to the laptop. When I edit the video in Corel I bring in the audio on a separate track but I leave the audio on the video track from the camera unmuted while I line them up. That makes it real easy to tell when the audio tracks from the two sources are either synched or so nearly so as to not matter, then I just select mute on the video channel and render the video.

BTW, one of those things I don't like about Corel is how it renders the native audio track from a camera. It will add random clicks and whatnot when you render the video. When I actually want to use the audio from the camera I have to export it to a .wav file and use Audacity to compress it to MP3, then bring it back into Corel as a separate audio track and synch it up, finally muting the audio on the video track before rendering. Apparently when Corel compresses the audio track it does so very poorly - but if you give it a pre-compressed MP3 it must not re-render it (or does so using a better codec, anyway).

(Oooo, I must be a geek, I used the word "codec" in a sentence!)

John
 
iMovie will let you drag the audio to a place where it syncs. If WMM can do this (or you could do this in Audacity), give yourself a marker in the vid of where exactly the audio starts recording. It makes syncing them easier.
 
I record audio into Pro Tools and the video into iMovie. I then sync the mixed Pro Tools recording with the video in iMovie, and then delete the audio track from the video. One thing that I have found quite helpful when syncing up the audio and video is to have some type of transient peak at the beginning. I use hand claps. It's a lot easier to sync up something with a sharp attack then it is to sync up strumming or singing. It's a similar idea to using a clapperboard.
 
Some useful tips here.

I use a Linux video editor called Open Shot. Very good and easy to use but one problem is that the audio waveform does not show in the editor which makes it very difficult to line up a separate audio track in the video editor which is why I use Audacity to make sure the separate audio track is exactly the same length as the video track. That way I can be sure of getting the audio and video synced properly.

I had experience of an early version of Windows Movie Maker in WinXP and that showed the audio waveform which was very useful for lining up tracks. It was easy to use but limited, though I suspect its functionality has increased somewhat since the days of WinXP.
 
I have done what you are trying to do. The easiest way to do this is start recording the audio and video at the same time... use a four-click intro (or eight if it feels more comfortable). When you are trying to sync the audio, don't remove the original audio from the video track. You can add the studio-quality audio and use the click track to line things up. Then, after they are perfectly sync'd, split the original audio from the video and you have a great audio track with the video with perfect timing.

What I do these days is record with a high-end consumer model video camera with an add-on recording studio quality microphone connected to the camera and mounted on a "C" bracket so that the mic is cabled to the camera, but mounted off camera. The mic has a wind-screen that is foam and also a "dead cat" (yes, that is what it is really called) --it's a fuzzy cover that prevents wind noise from being picked up by the mic. I used it during Hurricane Sandy and was amazed that even in such severe weather, it blocked most of the wind noise (hissing and buffeting) that would have destroyed the audio track.
 
Wow, some really useful info and tips there ! Thanks folks!
 
I have done what you are trying to do. The easiest way to do this is start recording the audio and video at the same time... use a four-click intro (or eight if it feels more comfortable).

I agree with you in principle but it depends on the hardware you are using. With the equipment I have, I have to start the audio and video separately as my video camera does not have an external mic input.

When you are trying to sync the audio, don't remove the original audio from the video track. You can add the studio-quality audio and use the click track to line things up. Then, after they are perfectly sync'd, split the original audio from the video and you have a great audio track with the video with perfect timing.

Any half-way decent software shouldn't remove the audio from the video clip when you extract the audio - just copies out the audio to a separate audio file. I always work with copies anyway. I keep the original on a separate hard disk so I can retrieve the video should I lose or mess up the version I am working on.

A further hint. Always record and edit audio using lossless formats. In practice that means either Wav or Flac (which applies a lossless compression). If you do have to use compressed formats for your video editor, only compress when you export the final audio from your audio editor and use the minimum of compression. It will all get compressed to hell anyway when you render (ie export) your final video.
 
First Video Done

Hi All - thanks for all the help - I ended up recording audio on the Zoom H2N and doing a small amount of work on cubase (bringing level up mainly) then synching it in windows live movie maker (this was a bit of a struggle - it doesn't seem to have a help menu??). My first real video is up now in the videos forum if you want to have a look - a version of strawberry fields.

Thanks again for all your help.

Ross
 
If you get the new final cut pro it's 199 now I think, it does it automatically. Import video, import audio, highlight them and synch, perfect every time within seconds, audio replaced. It's changed my life and anyone doing this on a regular basis needs this ability. You just don't know you need it! The other cool thing is it has many of Logic Pro's best plugins if you want to spruce it up or what I do is just pan for spacial sweetness.
 
This is what I do

I have a camera I record for video and a Mic for audio which records through garageband.
I turn both on to record, then I clap my hands together 3 times really loud. That's like a big slab that movie people use before action.
After I record, I bring both vid file and audio file into final cut.
I matchup the wav forms of the clap in both audio and video and its synced.
Cut off beginning where I start and end where I stop.
Finished.

Here's an example of a vid I just did doing what I said above.

There's a little bit of audio extra somewhere in the middle, I missed it during editing but you still get the idea.

 
I'm not sure that you want to get into this until your dissertation is published <g>. cheers mate, g2
 
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