Help removing plastic bag in audio at DVinfo.net

Stefan Gill · October 28th, 2014, 06:55 PM

Hi,

Wedding was indoors then moved to outdoors at the last moment, forgot to setup Zoon H4N recorder and my primary audio turned out terrible because I had a bag on the camera to prevent rain.

Any suggestions how to remove the plastic bag wrinkle noise (attached a .wav file) from the audio?

Use adobe premiere, have access to other adobe suite programs for audio.

Thanks,

Greg Miller · October 28th, 2014, 08:37 PM

That noise seems to be fairly broadband, and louder than the desired audio. In addition to the "crackle" sound which has a lot of HF component, there is the LF sound of wind buffeting the bag. Neither one has a specific frequency signature that would be easy to attack.

I suppose if you had an audio sample of just the noise, with no desired audio, you could try an adaptive filter such as the "Noise Reduction" filter in Audition. But those filters are really designed to remove background noise, whereas your noise is very much foreground. I can't imagine anything that would reduce it to the point of being unobtrusive.

Stefan Gill · October 29th, 2014, 05:59 AM

Thank you for your reply.

Rick Reineke · October 29th, 2014, 09:21 AM

You could try a spectral repair application. iZOtope Rx or SCS SpectraLayers Pro for example. It would be tedious and time consuming for sure.
OTOH, a vinyl click/crackle remover utility may help to some degree.

Greg Miller · October 29th, 2014, 03:24 PM

Rick, I tried a few different click/pop tools, but didn't mention it earlier since they weren't really successful. They did remove some, but not nearly all, of the plastic "crackle" noise.

There's a bigger problem, too. Apparently some sort of AGC was engaged, and as the buffeting wind creates a lot of LF energy, I hear the gain of the music pumping up and down. (It's not immediately obvious, since this audio sample is so short, but if you listen a few times you'll undoubtedly hear it.) So even if we could magically remove all of the crackle, and filter out all of the LF wind buffeting, we'd be left with "desired audio" that is rapidly pumping up and down in level.

Maybe in 50 years we will be looking at files like this as something trivial (just as we now consider motor noise, harmonic buzz, wow & flutter, as rather trivial today). But I will get down and kiss the feet of anyone who can turn this into a useable file today ... without hours and hours of manual adjustments.

Don Palomaki · October 30th, 2014, 10:17 AM

Can't think of any automatic fixer.

A couple possibilities - in most cases rather time consuming:
If any of the music was prerecorded, overdub those portions.
Would the participants be available to voice over their portions (blame it on excessive wind)?

For the dialog portion, to counter the AGC pumping and at least some wind noise use the level rubber bands on the audio time line to manually adjust dialog and "noise gate" the quiet portions.
The low-cut/hi pass filter can help with some of the wind noise.
Selective application of noise reduiction only to problematic spots may help.

Jim Andrada · October 30th, 2014, 11:45 AM

Damn - this is awful!

I sort of savaged it in Izotope and got it to sound more like crappy sound with noise rather than noise with crappy sound, albeit crappy sound with noise occasionally sounding like it was under water.

Which just made the pumping more noticeable

+1 on the audio equivalent of the reshoot filter being the only thing that would really save it.for a paying customer

Do you know a keyboard person who could play the music while listening through headphones?? Lord knows what would become of any dialog though.

FWIW

https://dl.dropboxusercontent.com/u/...20Izotoped.wav

Greg Miller · October 30th, 2014, 06:38 PM

Quote:

Originally Posted by Don Palomaki

For the dialog portion, to counter the AGC pumping and at least some wind noise use the level rubber bands on the audio time line to manually adjust dialog

But first you've got to get rid of all the broadband noise.

Quote:

Originally Posted by Don Palomaki

The low-cut/hi pass filter can help with some of the wind noise.

Believe me, this was the first thing I tried. The result just sounds like wind and plastic through a telephone line. It does nothing to improve the S/N. And eventually you reach the point where the desired audio is unrecognizable.

Quote:

Originally Posted by Don Palomaki

Would the participants be available to voice over their portions (blame it on excessive wind)?

ADR wedding vows. What's the world coming to?

You might get Woody Allen to dub it, ala What's Up Tiger Lily?

The only other solution is to use title cards.

Greg Miller · October 30th, 2014, 07:37 PM

Quote:

Originally Posted by Jim Andrada

I sort of savaged it in Izotope and got it to sound more like crappy sound with noise rather than noise with crappy sound, albeit crappy sound with noise occasionally sounding like it was under water.

That's better than I would have thought possible. Sounds like an Edison cylinder recording of a wedding, rather than a wedding with a volcanic eruption. My hat's off to you. No foot kissing, though, it's still not really useable. ;-)

Stefan Gill · October 30th, 2014, 08:04 PM

Quote:

Originally Posted by Greg Miller

You might get Woody Allen to dub it, ala What's Up Tiger Lily?

The only other solution is to use title cards.

Title cards, nice touch :)

Thanks for your help guys, I'm looping the background music around the vows, I did take the bag off minutes into the ceremony so it's not a complete loss.

Don Palomaki · October 31st, 2014, 05:09 AM

Subtitles for the ceremony? A great idea, especially if there are hearing impared people in either family.

Greg Miller · October 31st, 2014, 11:32 AM

I was joking about title cards, and hadn't thought of subtitles. But in seriousness, closed captioning could be beneficial. I wonder how many wedding videos are produced with this feature.

Jim Andrada · October 31st, 2014, 02:19 PM

@Gregg

Damn - I'll have to put my socks back on!!!!

I like the Edison cylinder analogy although the cylinder in this case seems to be a bit elliptical instead of round - that's what causes the pumping. Maybe it sat in the sun too long and the wax just sagged.

Subtitles for the vows - that would be neat. Convert the video to B&W, change it to 10 fps, add noise., print to film, scratch it up, walk on it, re-digitize.

Oh well - sorry I couldn't do better.

Greg Miller · October 31st, 2014, 09:53 PM

Jim,

Your file really sounded surprisingly good. I wouldn't have thought that possible without a lot of manual tweaking along the way. No it is not crystal clear, it lacks "life" after all the NR, but at least the noise is beaten pretty well into submission.

I wonder how well you could clean up the dialog with the same process. If you got the dialog clean, and if the wedding music was pre-recorded, the OP could get the original music track, sync it up, and drop it in in place of the windbag track.

Nice job, Jim!

PS:

Quote:

Originally Posted by Jim Andrada

I sort of savaged it in Izotope

Did you perhaps mean "salvaged"?

Jim Andrada · November 1st, 2014, 10:20 PM

Actually I did mean "Savaged"

I was running spectral repair and NR at strengths I wouldn't even dream of trying for any kind of quality result and just sort of hacking away with a digital machete so to speak.

It might be fun to see what would happen to the dialog if the OP could post a clip.

And thanks for the kind words - I really really like Izotope. I've had great luck with it - even once removed a horrendous noise (caused by a cellist hitting his chair leg with the instrument during a quartet performance) well enough that nobody could notice where it had been.

I have to admit that I'm not very scientific in my approach, I just hear something bad and go after it with whatever seems to make it sound better until I succeed or give up. I've found after using it for a couple of hundred hours that you can actually almost see the music by looking at the spectral display. Of course I know most of the pieces pretty well and usually have a full score handy while working.

October 28th, 2014, 08:37 PM	#2
Greg Miller Trustee Join Date: Jan 2011 Location: Pennsylvania Posts: 1,791	Re: Help removing plastic bag in audio That noise seems to be fairly broadband, and louder than the desired audio. In addition to the "crackle" sound which has a lot of HF component, there is the LF sound of wind buffeting the bag. Neither one has a specific frequency signature that would be easy to attack. I suppose if you had an audio sample of just the noise, with no desired audio, you could try an adaptive filter such as the "Noise Reduction" filter in Audition. But those filters are really designed to remove background noise, whereas your noise is very much foreground. I can't imagine anything that would reduce it to the point of being unobtrusive.

October 29th, 2014, 05:59 AM	#3
Stefan Gill Regular Crew Join Date: Jan 2012 Location: Levittown, New York Posts: 91	Re: Help removing plastic bag in audio Thank you for your reply.

October 29th, 2014, 09:21 AM	#4
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	Re: Help removing plastic bag in audio You could try a spectral repair application. iZOtope Rx or SCS SpectraLayers Pro for example. It would be tedious and time consuming for sure. OTOH, a vinyl click/crackle remover utility may help to some degree.

October 29th, 2014, 03:24 PM	#5
Greg Miller Trustee Join Date: Jan 2011 Location: Pennsylvania Posts: 1,791	Re: Help removing plastic bag in audio Rick, I tried a few different click/pop tools, but didn't mention it earlier since they weren't really successful. They did remove some, but not nearly all, of the plastic "crackle" noise. There's a bigger problem, too. Apparently some sort of AGC was engaged, and as the buffeting wind creates a lot of LF energy, I hear the gain of the music pumping up and down. (It's not immediately obvious, since this audio sample is so short, but if you listen a few times you'll undoubtedly hear it.) So even if we could magically remove all of the crackle, and filter out all of the LF wind buffeting, we'd be left with "desired audio" that is rapidly pumping up and down in level. Maybe in 50 years we will be looking at files like this as something trivial (just as we now consider motor noise, harmonic buzz, wow & flutter, as rather trivial today). But I will get down and kiss the feet of anyone who can turn this into a useable file today ... without hours and hours of manual adjustments.

October 30th, 2014, 10:17 AM	#6
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	Re: Help removing plastic bag in audio Can't think of any automatic fixer. A couple possibilities - in most cases rather time consuming: If any of the music was prerecorded, overdub those portions. Would the participants be available to voice over their portions (blame it on excessive wind)? For the dialog portion, to counter the AGC pumping and at least some wind noise use the level rubber bands on the audio time line to manually adjust dialog and "noise gate" the quiet portions. The low-cut/hi pass filter can help with some of the wind noise. Selective application of noise reduiction only to problematic spots may help. __________________ dpalomaki@dspalomaki.com

October 30th, 2014, 11:45 AM	#7
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Re: Help removing plastic bag in audio Damn - this is awful! I sort of savaged it in Izotope and got it to sound more like crappy sound with noise rather than noise with crappy sound, albeit crappy sound with noise occasionally sounding like it was under water. Which just made the pumping more noticeable +1 on the audio equivalent of the reshoot filter being the only thing that would really save it.for a paying customer Do you know a keyboard person who could play the music while listening through headphones?? Lord knows what would become of any dialog though. FWIW https://dl.dropboxusercontent.com/u/...20Izotoped.wav

October 31st, 2014, 05:09 AM	#11
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,488	Re: Help removing plastic bag in audio Subtitles for the ceremony? A great idea, especially if there are hearing impared people in either family. __________________ dpalomaki@dspalomaki.com

October 31st, 2014, 11:32 AM	#12
Greg Miller Trustee Join Date: Jan 2011 Location: Pennsylvania Posts: 1,791	Re: Help removing plastic bag in audio I was joking about title cards, and hadn't thought of subtitles. But in seriousness, closed captioning could be beneficial. I wonder how many wedding videos are produced with this feature.

October 31st, 2014, 02:19 PM	#13
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Re: Help removing plastic bag in audio @Gregg Damn - I'll have to put my socks back on!!!! I like the Edison cylinder analogy although the cylinder in this case seems to be a bit elliptical instead of round - that's what causes the pumping. Maybe it sat in the sun too long and the wax just sagged. Subtitles for the vows - that would be neat. Convert the video to B&W, change it to 10 fps, add noise., print to film, scratch it up, walk on it, re-digitize. Oh well - sorry I couldn't do better.

November 1st, 2014, 10:20 PM	#15
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Re: Help removing plastic bag in audio Actually I did mean "Savaged" I was running spectral repair and NR at strengths I wouldn't even dream of trying for any kind of quality result and just sort of hacking away with a digital machete so to speak. It might be fun to see what would happen to the dialog if the OP could post a clip. And thanks for the kind words - I really really like Izotope. I've had great luck with it - even once removed a horrendous noise (caused by a cellist hitting his chair leg with the instrument during a quartet performance) well enough that nobody could notice where it had been. I have to admit that I'm not very scientific in my approach, I just hear something bad and go after it with whatever seems to make it sound better until I succeed or give up. I've found after using it for a couple of hundred hours that you can actually almost see the music by looking at the spectral display. Of course I know most of the pieces pretty well and usually have a full score handy while working.