Can someone explain clipping to me, and how to repair audio files?

[snafubaby]

I'd appreciate an easy explanation of clipping, and what it is, and how to repair files that have clipping.

Thanks very much!

[jman98]

Explanation here:
http://en.wikipedia.org/wiki/Clipping_%28audio%29

The article suggests that repair is extremely difficult. I have no practical experience in this with any tools.

[jagabo]

Say you decide to represent an audio waveform using single digits for the amplitide, 0 to 9. You digitize an audio source and get something like:

0 1 2 3 4 3 2 1 0 1 2 3 4 3 2 1 0



That's a simple sawtooth wave that starts at 0k, rises to 4, falls back to 0, and repeats

You decide that's not loud enough so you double the volume:

0 2 4 6 8 6 4 2 0 2 4 6 8 6 4 2 0



That's fine. It has the same basic sawtooth shape but the peaks are now twice as high. Instead of ranging from 0 to 4 they range from 0 to 8.

Instead of doubling the volume you decide to quadruple it:

0 4 8 12 16 12 8 4 0 4 8 12 16 12 8 4 0

But your system only uses single digits at each sample. So all those samples that are two digits need to be reduced to one. The largest value your system can represent is 9. So all the values over 9 become 9:

0 4 8 9 9 9 8 4 0 4 8 9 9 9 8 4 0



The peaks of your nice sawtooth wave have now been "clipped" off at 9. Those clipped peaks sound very harsh compared to your original source.

How do you fix these clipped peaks? Looking at the clipped waveform it may be easy to guess it started out as a sawtooth. You would just reduce the amplitude then try to reconstruct the peaks by interpolating the existing data:



But what if the original waveform wasn't a simple sawtooth? What if the peaks had had a complex shape? Once the peaks have been clipped there is no way to know exactly what they originally looked like. There is no way to perfectly reconstruct the original sound. This is why it's important never to clip in the digital realm.

[budwzr]

AFA clipping goes, is that in an MP3 or AAC? They have a playback gain that you can change.

Try: MP3Gain http://mp3gain.sourceforge.net/download.php

An easy explanation is that clipping comes from too high a gain during recording, or poor editing after. And the peaks(loud parts) get cut out.

Clipping sounds like a momentary hiss.

[Munster1]

There is a VST plugin called ReLife at http://www.terrywest.nl/utils.html which is a pretty handy tool for restoring clipped audio. It can't perform miracles, but it is worth a try.

[budwzr]

There is a VST plugin called ReLife at http://www.terrywest.nl/utils.html which is a pretty handy tool for restoring clipped audio. It can't perform miracles, but it is worth a try.

Do you use Ableton?

[Munster1]

Do you use Ableton?

I've never used it. Why do you ask?

[budwzr]

Do you use Ableton?

I've never used it. Why do you ask?

I was thinking you're a musician or remixer.

I tried that plug, seems pretty good, but what are the "1,2,3" buttons?

[Munster1]

I think the 1, 2 and 3 buttons are different methods for peak restoration. I've only used button 1.

I'm not involved in music production in any way. I can't remember how I heard about ReLife and found that website.

[zoobie]

I heard a brief hissing in one of my productions
ReLife looks interesting...I'm in music production so I think I'll give it a shot...Can't hurt

[Gavino]

There is also the Clip Fix plugin which comes with Audacity.
https://forum.videohelp.com/threads/331240-Does-anyone-know-how-to-use-Clipfix-with-Audacity

[lacywest]

I use Cool Edit Pro 1.2a or Cool Edit Pro 2.1 ... to fix any clipping I see in my audio files

[budwzr]

I heard a brief hissing in one of my productions
ReLife looks interesting...I'm in music production so I think I'll give it a shot...Can't hurt

Hey, that's cool, I like to create music too, to go along with videos. I used to just throw copyright songs in them, but I realized it's kind of cheesy, and amateur. Now I can claim full credit, or criticism. Hahaha.

I like Ableton, but I started out with Cinescore, then went to Acid Studio. Ableton really opened my mind to the world of warping and samples. I'm no pro, but it's great fun.

I have an LPK25 for midi keyboard, LPD8 for pads, and a Launchpad. I'm not a DJ, but the launchpad sure makes it easy to be one.

Anyway, as a side note to this thread, sometimes I overdub my older commercial music in Ableton, as opposed to trying to "EQ" the song into the 21st century. The main thing is to get some kick bass in there, and I might throw in some tambs or hihat, just to freshen it up. If you don't overdo it, it sounds like a remaster, hehehe.

So anyway, nice meeting you, and maybe we'll cross paths again and have a good exchange of ideas or insights!

Peace

[Cornucopia]

yeah, lacywest, that Cooledit De-clip/Peak Restore function is one of the best I've seen. None of them can work miracles, but that's a pretty safe bet for most material.

Scott

[lacywest]

yeah, lacywest, that Cooledit De-clip/Peak Restore function is one of the best I've seen. None of them can work miracles, but that's a pretty safe bet for most material.

Scott

I have preset settings already laid out.

-.5 db
-1.0 db
-3.0 db
-6.0 db ..... and so on ... I have the whole folder copied from ... C:\Program Files\Cool Edit Pro

and if I have to re-install Windows ... or on a different PC ... I just copy and paste the Cool Edit Pro folder ... and then do the actual setup install into that folder ... and all my presets stay.