Help me edit a specific sound out of a home video (DV-AVI)

June 26, 2008 8:32 PM

Is there free video editing software that can edit audio as well? If so, how do I remove a specific sound from my video?

I was planning on asking for suggestions on video editing software, but I realized that's been covered and it's not really specific enough for what I need. I basically need two things, 1) video editing software that can edit sound as well (or just some method to edit sound in a video) and 2) some advice on how to edit the sound (see below). Oh, and my budget for this is no more than $0. Well okay, $5.

Here are the specifics. Don't need anything fancy for video editing. Cutting, splicing, standard effects, etc. will suffice. It should be able to accept and save in DV-AVI. As far as advice on sound editing: In this particular video my tripod was making intermittent creaking sounds when I moved the camera and it's quite distracting when watching the video. I'm desperately hoping there's a way to edit the audio track(s) and suppress/remove the creaking sound. I can try to mask it with music or something but I still want to be able to hear the other sounds in the video. I'm somewhat familiar with Audacity if that helps. Please tell me I'm not SOL...

Thanks!

posted by jluce50 to computers & internet (7 answers total)

What OS are you using? On Linux, Kino and Cinelerra are both nice apps (the former is friendlier than the latter; the latter is much more powerful but challenging to learn), but I'm unfamiliar with Windows and on OS X I've just used iMovie (download iMovie HD from Apple's site if you're unfortunate enough to be stuck with the newest version, which is more or less worthless).

On any of these platforms, you can use the command-line tool ffmpeg to split the audio from a video file into a separate file, edit it in Audacity, and merge the audio and video together again. You probably want to do this before you import the footage into your editor.

For something like a tripod squeak, though, you're probably SOL. Your best bet is to use a graphic or parametric EQ and try to isolate the frequencies where the majority of the tripod squeak is happening, an hope that in pulling them down you don't stomp all over the remaining audio. When I was in film school, I spent many long nights trying to do this with hums of various kinds (Never, EVER shoot a video in a working convenience store. Those freezer compressors? Totally obnoxious.) and came to the conclusion very rapidly that it's FAR easier to go out of your way to eliminate unwanted noise on set than it is to try to get rid of it later.
posted by Alterscape at 8:45 PM on June 26, 2008

agreed about a specific sound like from a tripod being borderline impossible to remove.

You didn't mention what the "other sounds" are, but the only way to really do this is to drop all your audio and replace it. If it was shot outside in a park, download some "park ambience." if there are specific sounds like footsteps, add sound effects. If there's dialogue, have the actors "loop" to match their lips. This isn't ideal but I have done it with tolerable results.

If you can, you might just want to reshoot, and this time use an external mic and listen through headphones as you record.
posted by drjimmy11 at 9:12 PM on June 26, 2008

Sorry, should have mentioned that I'm on XP. The tripod noise is pretty intermittent and where there is dialog it isn't as noticeable. I'm mainly concerned with the times the noise appears when it is otherwise relatively quiet. I'm hoping that in those cases I can just copy and paste some ambient noise over the offending sections.

Sounds like ffmpeg and Audacity are the way to go. Will ffmpeg handle re-combining the audio and video? Any tricks to making sure it syncs properly?

Also, are there any GUI front ends for ffmpeg? The less command line work I have to do, the better.

Good info, thanks guys.
posted by jluce50 at 7:47 AM on June 27, 2008

I've dealt with this. Using a video editor like Cinelerra (it's on the dynebolic live cd) is helpful because you can skip ahead & look for a shift in camera angle.

On my tripod, at least, the noise is across the spectrum, so there's no EQ that can help; instead, I briefly muted the audio. You can check this by switching the Audacity display to spectrograph IIRC.
posted by Pronoiac at 2:07 PM on June 27, 2008

You're right about the tripod noise being all over the spectrum. I've been playing with Audacity and it looks like the Noise Removal and Hard Limiter effects may be helpful.
posted by jluce50 at 7:46 PM on June 27, 2008

If this is a one-shot project, you can get a 30-day free trial of Vegas Movie Studio (which has excellent sound editing capabilities) here. If you need more time, you can download trials of the other two versions at 30 days a pop each for a total of 90 days of free editing.
posted by zanni at 3:22 PM on June 28, 2008

As I was mulling this over I remembered I had a couple OEM copies of Nero 7 Essentials and Ulead VideoStudio 8. I had installed them both at one point and didn't think either did a very good job at DVD burning (I didn't try the video editing), but I particularly hated Nero. So, I went ahead and installed Ulead VS8 and I'll be damned if it's not a pretty good video editor! It can do some audio editing but I went ahead and took care of that in Audacity since it gives me far more control.

As far as the tripod noise, here is what I did. First I used the Hard Limiter effect to remove all sound except vocals. I then added some music to fit the mood that served to mask the transition from silence to vocals as well as the ambient noise that was present during the vocals. For the tripod noise during vocals I just went in a removed the spike. They were usually short enough that you can't hear the dropout when played at full speed.
posted by jluce50 at 7:10 AM on June 29, 2008