OT: Audio Beeps & Dropouts

[r]Evolution wrote on 6/28/2008, 1:10 PM
I recently shot a 3hr Single Camera Presentation with a Sony TRV900.
I used 2 Panasonic AY-DVM63MQ & 1 TDK DVM60 MiniDV Tapes all in SP Mode.

Everything looks great and the audio sounds good on the 2 Panasonic Tapes... but the TDK Tape has numerous Audio Dropouts & Digital 'Beeps' which could not be heard during recording. The Dropouts & 'Beeps' are sporadic.
This was a Book Signing - the Q&A section is the section that is messed up. Although it's not the most important section, there were some very interesting questions asked & answered. Naturally, I would like to include it in the DVD.

It will be tedious but I may be able to use Sony Noise Reduction tools to remove, disguise, or otherwise hide the 'Beeps'... but the DropOuts have me perplexed.

I found this software BeepFix but it doesn't seem to work with XP Pro.

- Anyone know of a software program that can analyze a file and correct Audio Dropouts?
- Anyone have any methods for correcting problems such as this?

Comments

Steven Myers wrote on 6/28/2008, 1:58 PM
iZotope RX

The beeps will be no problem.

RX does a great job with drop-outs, too. But it won't guess and insert English words or sentences.
Still, if a drop-out is real quick and happens entirely during a word, you might be in luck.
johnmeyer wrote on 6/28/2008, 2:37 PM
Yup. Izotope RX was born to do exactly what you are asking about. 100% certainty that it can fix your problems (although it may take you a little time, depending on how many you need to fix).
[r]Evolution wrote on 6/30/2008, 11:14 AM
iZotope RX($349) or iZotope RX Advanced($1199)?

Do these two processes sound like what I need to do?
Denoiser
Removes broadband noise with natural sounding results
Spectral Repair
Fixes intermittent noises, corrupted intervals and even gaps in audio

The entire tape (@45 minutes) is like this... but the 'Beeps' all sound like they are the same frequency. The Audio Dropouts are of different lengths so I'm not sure how they will turn out. I guess there's only one way to find out.

Thank you guys for the info.
johnmeyer wrote on 6/30/2008, 11:55 AM
You only need the "cheap" version.

Spectral repair, using "replace" is where you should start for both the gaps (missing audio) as well as the beeps. The beeps will show up as one or more horizontal bands in the frequency display. Use the combo selection tool (both frequency and time simultaneously) and select just the frequency you want to remove. If you have several harmonics, you must repeat for each.

Here's a screen shot that shows how it works. Note that I have selected the first of two main harmonics of a baby crying during a wedding. After removing that one, I'll remove the next. There are some subtle higher-order harmonics, but I usually leave those. The residual sounds like the baby is crying way in the back row somewhere rather than (as was the case) just a few feet from the mic.

johnmeyer wrote on 6/30/2008, 12:06 PM
P.S.

Here's a before/after of the baby "cry." Nothing earth-shattering, except that without Izotope, this is impossible.

Hey, I guess that IS earth-shattering. Too bad Sony Creative Software isn't doing innovative stuff like this anymore.

Baby Cry

Baby Cry Removed

Links good for seven days.
[r]Evolution wrote on 7/2/2008, 10:06 AM
Wow! This IS Earth-Shattering.
I loaded a small clip into RX to see what it could do for my 'Dropouts'. I'm impressed. It worked its magic and replaced the Blank Space w/ similar sounds. It's not perfect since it can't replace words but it definitely makes it more bearable. There tends to be a bit of an 'Electronic' resonance/residual sound but I'm sure that if I knew RX a bit better I could get it to be as if it never happened.

Spectral Repair is a bit tedious as it appears that I am unable to select multiple regions and batch them. (Maybe it's there... I just don't know where/how)

This is definitely Money Well Spent. I can see me using these repair methods time and time again... and I can recall times before when I wish I had it. Looks like it can do a whole lot of things along the lines of Sony Noise Reduction. Maybe we'll see some of these features creep into Sony Noise Reduction so it can be used as a Plug-In.

--That's cool how you removed the Baby Crying.
johnmeyer wrote on 7/2/2008, 4:15 PM
There tends to be a bit of an 'Electronic' resonance/residual sound but I'm sure that if I knew RX a bit better I could get it to be as if it never happened. I get this too when replacing gaps. To minimize, try playing around with the amount of "before" and "after" that is used, and also with the before/after weighting. Also, try altering the number of bands.

I guess I just listed the entire set of controls, so I didn't give you much insight.

You should also try the "partials + noise." Concentrate on one particular replacement and experiment with these controls. It should only take a few minutes. I just did a quick test and was able to get better results for my situation using the partials + noise.

The product is absolutely amazing.
Steven Myers wrote on 7/2/2008, 4:24 PM
This is my first attempt with RX. The guide's cell phone went off at a bad time. Fortunately, the harmonics were pretty well defined:



There are some artifacts, but the result ain't too bad:

http://www.yankeetown.org/steve/public/RX/TroutPHONE.html

johnmeyer wrote on 7/2/2008, 7:31 PM
Except for the "after" sounding a little hollow, it sounds great. I assume you used either "replace" or "attenuate" and that you very carefully selected each individual horizontal line, fixed that, and then went to the next horizontal line.

I usually start with the "fattest," brightest lines. After doing one or two, I play it again to see if I can live with the result. Restoration is always a balance between fixing the bad, but without creating new havoc. Sometimes doing less gives a better result. However, in the end, what matters is how it sounds to you.

Again, nice job.
Steven Myers wrote on 7/2/2008, 8:35 PM
Attenuate.
Yep, I went brightest first, next brightest, until I couldn't hear the phone.
As you say, it's always a balancing act. In this case, I was annoyed enough by the phone to be willing to sacrifice my way into "a little hollow."
Now that I've used the software for a few months, maybe I'll do better if the problem ever reappears.
[r]Evolution wrote on 7/2/2008, 10:07 PM
- Do you guys know of a way to 'Auto Select' the Dropouts or Silent Areas?

Seems like I can only EXPORT. I have Four 15 minute files and I would like to save my progress and finish tomorrow.
- Is there a way to SAVE your RX Session?

They need a 1Click option where you can set-up your parameters then have it analyze the entire file applying the Spectral Repair per your settings.
or at least have it to where you can Double-Click in a Silent area and have it select that area.
johnmeyer wrote on 7/2/2008, 11:34 PM
Next time try Replace or partials plus noise. Attenuate usually provides the fewest glitches, but as you experienced, since it makes no attempt to fill in the frequency "holes," you can get unwanted side-effects, much like using multiple notch filters in Sound Forge. The beauty of the replace and partials plus noise modes is that they attempt to intelligently fill in these frequency/time gaps with material from adjacent times and frequencies. When you get the correct balance of settings, the results can be pretty magical, and the remaining sound usually is quite natural to the ear.
Steven Myers wrote on 7/3/2008, 2:10 AM
Thanks, John. Good thinking.