How to remove specific sounds from a video ? ? ? at DVinfo.net

William Wilson · October 7th, 2009, 01:33 AM

The content we shoot requires us to have a still cam on burst mode during a critical portion of our videos. We are trying to learn a good way to eliminate or at least minimize this sound in the video without replacing the audio as we really need original (real) the sound track from the talent in the video. Is there any audio editing secret that would help us accomplish this?

We edit in Premiere Pro CS3

Thanks!

Bill

Floris van Eck · October 7th, 2009, 03:30 AM

iZotope RX, Soundbooth, Soundtrack Pro... those are the applications you should be looking at. iZotope is probably your best option. It won't be very easy though.

Steve House · October 7th, 2009, 03:56 AM

Quote:

Originally Posted by William Wilson

The content we shoot requires us to have a still cam on burst mode during a critical portion of our videos. We are trying to learn a good way to eliminate or at least minimize this sound in the video without replacing the audio as we really need original (real) the sound track from the talent in the video. Is there any audio editing secret that would help us accomplish this?

We edit in Premiere Pro CS3

Thanks!

Bill

Noise removal software filters specific freqencies and works best with a continuous sound like a hum. Your camera sound is broadband and intermittent, making it very diffcult to edit out without affecting the rest of the sound. Is the camera out of shot? If so, how about making a sound-deadening blimp to put it in?

Bob Hart · October 7th, 2009, 04:19 AM

My personal preference would be to shoot several takes of two versions, some with the stills camera operating, then some with the stills camera not operating so the actors "pacing" remains the same, then perhaps copy over the dialogue or background sound in post. - It is likely that in edit, the insertion of "burst-mode" stills may require some time stretch or cut, so a background ambience would be good to have as well as the "stills cameraless" takes. - More options is all.

Seth Bloombaum · October 7th, 2009, 10:29 AM

Blimping is good, with Steve on that.

Is there no still camera that can burst without making a lot of noise? However you solve this problem, it will take much less time and the eventual soundtrack will be of better quality if you can somehow avoid recording this sound, rather than trying to take it out later.

There may be other issues. For example, if you are on automatic audio levels with a camera mounted mic, and the stills photographer is next to the video camera, that's probably the worst possible setup for this issue. (mic is closer to the still cam than to the subject, auto tends to pump up background sounds.)

Steve House · October 7th, 2009, 10:32 AM

Quote:

Originally Posted by Seth Bloombaum

Blimping is good, with Steve on that.

Is there no still camera that can burst without making a lot of noise? ....)

SLR cameras with mirror lockup can reduce a lot of the noise. Then there's the new Leica M9 which actually has a silent "stealth" mode.

Jim Andrada · October 7th, 2009, 10:48 AM

Is what you're worried about the "clunk" sound of the mirror rising and falling? How long are the bursts/ how many frames in a burst? Can the mirror be locked in the up position if this is the issue?

I think Izotope RX can probably do it well, but getting this kind of noise out is usually labor intensive, ie you have to find each instance and apply appropriate reconstruction and if the noise re-occurrs continuously there may not be enough "noise free" content betwen the noises to make it work. So it might be too labor intensive to be practical if you're dealing with dozens of occurrences. Sort of like audio rotoscoping I guess!

Strange thought - maybe it would work by calling the continuous dialogue "noise" and "removing" it to a new file. I've done things like that in the past with RX and they've worked, but whether it would work in this case I couldn't tell without trying it.

Do you have an example you could post a link to? I'd be happy to take a shot at it, but without hearing what it sounds like I'd tend to agree with the other posts that the best way is to keep the noise out of the track in the first place if at all possible.

Here's a link to a before and after example of something I just did with RX

http://www.dvinfo.net/forum/all-thin...rx-i-love.html

Jim Andrada · October 7th, 2009, 10:51 AM

As a follow up to what Steve just said, some of the newer cameras (Lumix four thirds etc) don't have mirrors at all. They also tend to be cheaper than Leicas (maybe 10% to 20% of the price!}

Bob Hart · October 7th, 2009, 11:33 AM

Is the stills camera actually in the shot as part of the story. If not could you not simply shoot with a second video camera the same scene from the SLR camera POV, extract the appropriate frames and insert them into the edit as faux stills.

Alexey Lukin · October 10th, 2009, 12:44 PM

If the sounds that you are removing are all similar, try doing a time-frequency selection and using a "Find Similar Event" feature of RX.

Nathan Moody · October 10th, 2009, 03:47 PM

Rather than look at broad-band noise removal, another approach is more narrowband filtering and EQ. Motor drives are buzzy-sounding, making them somewhat broadband noise sources, but the mirror slap and/or motor noise can be isolated if you have a good spectrum analyzer (the Channel EQ plugin in Logic and Soundtrack Pro, for example, or any number of 3rd party standalone apps). You won't eliminate it, but depending on the rest of the audio track (which you've not described), you can minimize its apparent volume.

It also depends on what other production audio you have going. Can you get mics on a boom closer to the talent? Can you opt for more directional mics (cards, hypers) that point away from the motor drive sound source? Use wireless lavs on the talent? Cover the top of the camera in furniture moving blankets (that's no joke, totally typical techniique)? Multiple options of the above? If you have any latitude in this regard, it'll be way better than anything you try to do in post.

October 7th, 2009, 01:33 AM	#1
William Wilson Regular Crew Join Date: Aug 2007 Location: Las Vegas, NV Posts: 69	How to remove specific sounds from a video ? ? ? The content we shoot requires us to have a still cam on burst mode during a critical portion of our videos. We are trying to learn a good way to eliminate or at least minimize this sound in the video without replacing the audio as we really need original (real) the sound track from the talent in the video. Is there any audio editing secret that would help us accomplish this? We edit in Premiere Pro CS3 Thanks! Bill __________________ Bill Wilson PK Productions ~ From Mild to Wild Las Vegas, NV

October 7th, 2009, 04:19 AM	#4
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	My personal preference would be to shoot several takes of two versions, some with the stills camera operating, then some with the stills camera not operating so the actors "pacing" remains the same, then perhaps copy over the dialogue or background sound in post. - It is likely that in edit, the insertion of "burst-mode" stills may require some time stretch or cut, so a background ambience would be good to have as well as the "stills cameraless" takes. - More options is all. Last edited by Bob Hart; October 7th, 2009 at 04:24 AM. Reason: error

October 7th, 2009, 10:29 AM	#5
Seth Bloombaum Inner Circle Join Date: Sep 2003 Location: Portland, Oregon Posts: 3,420	Blimping is good, with Steve on that. Is there no still camera that can burst without making a lot of noise? However you solve this problem, it will take much less time and the eventual soundtrack will be of better quality if you can somehow avoid recording this sound, rather than trying to take it out later. There may be other issues. For example, if you are on automatic audio levels with a camera mounted mic, and the stills photographer is next to the video camera, that's probably the worst possible setup for this issue. (mic is closer to the still cam than to the subject, auto tends to pump up background sounds.) __________________ 30 years of pro media production. Vegas user since 1.0. Webcaster since 1997. Freelancer since 2000. College instructor since 2001.

October 10th, 2009, 03:47 PM	#11
Nathan Moody Regular Crew Join Date: Feb 2009 Location: SF Bay Area, CA, USA Posts: 78	Rather than look at broad-band noise removal, another approach is more narrowband filtering and EQ. Motor drives are buzzy-sounding, making them somewhat broadband noise sources, but the mirror slap and/or motor noise can be isolated if you have a good spectrum analyzer (the Channel EQ plugin in Logic and Soundtrack Pro, for example, or any number of 3rd party standalone apps). You won't eliminate it, but depending on the rest of the audio track (which you've not described), you can minimize its apparent volume. It also depends on what other production audio you have going. Can you get mics on a boom closer to the talent? Can you opt for more directional mics (cards, hypers) that point away from the motor drive sound source? Use wireless lavs on the talent? Cover the top of the camera in furniture moving blankets (that's no joke, totally typical techniique)? Multiple options of the above? If you have any latitude in this regard, it'll be way better than anything you try to do in post. __________________ designer of media for eyes and ears sound design and field recording at http://www.noisejockey.net/blog

October 7th, 2009, 03:30 AM	#2
Floris van Eck Major Player Join Date: Jan 2006 Location: The Netherlands Posts: 993	iZotope RX, Soundbooth, Soundtrack Pro... those are the applications you should be looking at. iZotope is probably your best option. It won't be very easy though.

October 7th, 2009, 10:48 AM	#7
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Is what you're worried about the "clunk" sound of the mirror rising and falling? How long are the bursts/ how many frames in a burst? Can the mirror be locked in the up position if this is the issue? I think Izotope RX can probably do it well, but getting this kind of noise out is usually labor intensive, ie you have to find each instance and apply appropriate reconstruction and if the noise re-occurrs continuously there may not be enough "noise free" content betwen the noises to make it work. So it might be too labor intensive to be practical if you're dealing with dozens of occurrences. Sort of like audio rotoscoping I guess! Strange thought - maybe it would work by calling the continuous dialogue "noise" and "removing" it to a new file. I've done things like that in the past with RX and they've worked, but whether it would work in this case I couldn't tell without trying it. Do you have an example you could post a link to? I'd be happy to take a shot at it, but without hearing what it sounds like I'd tend to agree with the other posts that the best way is to keep the noise out of the track in the first place if at all possible. Here's a link to a before and after example of something I just did with RX http://www.dvinfo.net/forum/all-thin...rx-i-love.html

October 7th, 2009, 10:51 AM	#8
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	As a follow up to what Steve just said, some of the newer cameras (Lumix four thirds etc) don't have mirrors at all. They also tend to be cheaper than Leicas (maybe 10% to 20% of the price!}

October 7th, 2009, 11:33 AM	#9
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Is the stills camera actually in the shot as part of the story. If not could you not simply shoot with a second video camera the same scene from the SLR camera POV, extract the appropriate frames and insert them into the edit as faux stills.

October 10th, 2009, 12:44 PM	#10
Alexey Lukin New Boot Join Date: Feb 2009 Location: Moscow, Russia Posts: 10	If the sounds that you are removing are all similar, try doing a time-frequency selection and using a "Find Similar Event" feature of RX.