New plug-in effect - PopMute

Yes, thanks.

Sorry, I did of course mean 10 samples! And Click Removal also seems fairly ineffective on even narrow spikes if they are not very much louder than their surroundings.

What do you think is the best route to getting a single click/pop removal effect that removes a wider range of disturbances? Can Click Removal ever be improved? Is the better route to make Repair work on much longer selections? The two proof-of-concept attempts at doing this a while ago were apparently fairly successful.

Meantime should PopMute be “starred” as a Wiki candidate (even if you eventually try to make it more intelligent)? I guess it only needs a single page of “help”?



Gale

This could be classified as a bug report with a workaround found. I don’t know whether the issue is in Audacity itself or in the effect I was using. I use this effect often and have never seen this happen before. I’m using Windows XP, SP3.

I had 162 ms selected about 30 minutes into a long track (project has two tracks but the other track is vacant (no clip) in this area). I tried to use Pop Mute (tried both versions) and consistently got an error box:There is not enough room to paste the selection. After the operation, the selected part had been deleted :open_mouth: . I undid the operation and tried setting the threshold so Pop Mute would do nothing. Same result. I undid it again. I tried setting the Attack/Decay parameters very short. Same result. Undo. Changing the length of the selection made no difference either. Then I tried duplicating the selection and operating on the copy with my original parameters set. Success :wink: !

My curiosity now stoked, I tried another experiment: I split the original track (selection was now a clip within the track). Pop Mute worked on the clip just as it had on the copy.

One more experiment: I undid the effect and duplicated the clip. Length of the new track was 7176 samples. I applied Pop Mute to the copy, then clicked on the track panel to make sure I had it all selected. Length was still 7176 samples.

Hi Dick,

Thanks for the report.

PopMute is a third-party plug-in and not directly a part of Audacity, so it’s best to post feedback/bug reports directly to the third party rather than in a general Audacity part of the forum. In this case, I’m the third party and this is currently the “home page” for this effect (I presume that you downloaded the PopMute plug-in from this topic).
I’ve moved your post here so that it is together with other discussion for this plug-in.

When testing plug-ins (and software in general), use the most current version, which in this case is version 0.2 (experimental).

That’s curious, because that error message is not generated by the plug-in.

I’ve not been able to reproduce the problem.
Did the problem occur only with that one audio track, or are you able to reproduce the problem with other audio tracks?
Which exact version of Audacity are you using (Look in Audacity “Help menu > About Audacity”)

I’m using “1.3.12-Beta (Unicode)” on Windows XP, SP3. Pop Mute is an effect I’ve probably used fifty times now and I’ve never encountered this problem before.

After several hours of experimentation and two Audacity crashes (I was writing a log of the experiments to send as reply, but the system logged me out and I lost the text), I have some solid and some tentative conclusions:

Solid conclusion (just one):

This is not a pattern-sensitive problem. It doesn’t even matter whether Pop Mute actually does anything. Under the conditions which cause it, the selection can be anywhere in the clip.

Tentative conclusions:

It has something to do with there being a split somewhere after the selected region. If there’s enough (5 seconds is enough and 1 sample seems not to be) gap at the split, it does not happen. It also does not happen if “Editing a clip can move other clips” is Checked. It also seems there has to be something peculiar about the split. When the region selected for the effect is itself a whole clip (using Split with the same time selection) the problem does not occur.

Not all effects are bothered by the conditions that evoke it in Pop Mute. Hard Limiter for example is not.

Two circumstances suggest there’s something abnormal about the split associated with this problem:

1: Both Audacity crashes occurred thus:
I had invoked Pop Mute unsuccessfully, which deleted the selected region, then used Undo to restore it. “Editing a clip can move other clips” was Unchecked at the time. Then I Checked “Editing a clip can move other clips”. The crash occurred upon clicking Effect (the list did not appear). If I did not invoke Pop Mute / Undo before Checking “Editing a clip can move other clips”, there was no crash upon clicking Effect. Neither does the Pop Mute / Undo sequence alone set Audacity up for a crash - I did this many times during the experimentation.

2: I had encountered a problem yesterday during the process that resulted in the splits. I was replacing a cycle of audio with a nearby cycle to eliminate a click. I had duplicated a cycle with a bit of overhang on each side. I used Split New to both open a space for the new cycle and save the old one. I time-shifted the new cycle to align with the vacancy, then trimmed it using the time selection from Split New. I then tried to drag it vertically into the space, and I couldn’t. Then I remembered it can’t be selected at the time, so I used Ctrl-Shift-A. I still couldn’t drag it into place. I’m new at using the vertical dragging feature (have used it exactly once before), so maybe I’m missing something here. I wound up selecting/copying/pasting the new cycle into the space. Now I wonder if the vertical dragging problem occurred because the new cycle didn’t quite fit into the gap, and Paste somehow produced an overlap. “Editing a clip can move other clips” was Unchecked during this entire process.

Very curious. Thanks for the detailed report.
I don’t think the problem is specifically to do with this effect, but rather this effect has shown up some underlying bug. It seems that Audacity has lost track of where the data is in the track.
Were all of these observations from the same Audacity Project?
How big is the project?

All observations are from the same project. I’ve since joined the splits to avoid further trouble, and removed the copy track. The project contains around 90 minutes of audio on two tracks, but only one track (the longer one) was involved in the reported tests and observations. If I were going to attempt making a bug demo I’d make a much shorter one. I can’t resurrect the problem from this project anyway now that I’ve joined the splits. I’m using dialup, BTW, so an Audacity project would have to be pretty short to be practical for sending.

Where does Audacity save its .aup.bak file nowadays on Windows XP? Maybe the culprit is still in there.

I think that as this is (so far) just a one-off there’s probably not much point in pursuing it at the moment as I think that we are unlikely to be able to locate the problem now. However, if it occurs again, please write back and we’ll see if we can pin it down.

If it does happen again and I save a copy of the .aup file without the data, would that be useful? I’m thinking a close look at the waveblock records might turn up a clue.

If it’s a large project, the waveblock records will make pretty heavy reading, and without the actual data may not show very much. Let’s hope it doesn’t happen again, but if it does let’s hope it’s a really small project :wink:

@DickN - 1.3.12 on Windows has known issues that clicking around in (and after using) effects can crash, also splitting can create unwanted zero length clips which can also cause crashes. Please update to the current 1.3.13 Beta. I would hope that would cure the problem.

1.3 Beta no longer saves .aup.bak files.


Gale

Will do, thanks. Been looking forward to that Noise Removal upgrade.

This occurs in both versions of Pop Mute (single and separate attack/release controls). I believe it is associated with bipolar “pop” waveforms when the time and threshold settings result in overlapping responses to peaks of opposite polarity.

Result looks like this with settings of:
Threshold = -3.3
Mute Level=-10
Attack/Decay=18

With Attack/Decay set to 10, this doesn’t happen.
PopMuteGlitch.PNG
There was some discussion in the past about whether stereo tracks should be treated as 2 mono tracks or kept in balance. IMO, while the typical (or rather originally intended) use should treat the channels independently, I have recently found another handy use in which I want both channels to be affected jointly. After applying filters etc., I sometimes find brief overshoots that produce clipping. Rather than adjust the level globally to eliminate a couple of clipped peaks, I use Pop Mute with a high threshold setting and a small Mute Level setting to put a small distortion-free dip in the amplitude where it exceeds 0 dB. While such a brief channel imbalance is not really noticeable, I just have the feeling that keeping the balance is the right way to do it. I still use both versions.

Should have mentioned, I’m using 1.3.14 Alpha, May 23. I’ve seen similar glitches using older Audacity versions but this time I saved the sample to look at when I finished the project.

  • Dick

OK, thanks for the report, I think I’ve found the problem.
With those exact settings the peak detector is hitting a second peak of opposite polarity before it has recovered from the first peak, so the waveform is being pushed down “below silence” and inverting the signal. Then as the gate begins to open again the signal “pops” back to the correct polarity, causing that vertical line.

To actually avoid this problem, the attack/release times need to be shorter, (so that it catches each peak separately), or a lower threshold (so that it treats both peaks as one click) but in this version I’ve mitigated this unwanted possibility by preventing the waveform from being pushed into reverse polarity. Give it a go and see if this works better for you.
popmute.ny (1.85 KB)

Thanks, Steve! I have a bunch of projects in the queue, will let you know how it goes.

  • Dick

I promised to let you know how it goes using your new Pop Mute. That was quite a while ago. I just haven’t run into another waveform that triggers the problem in the earlier version, so nothing new to compare. I have encountered a case where many closely-spaced peaks drove the output abruptly to silence for a short time, but I neglected to save the input for reporting. FWIW, I tried all 3 versions on that waveform and got the same result.

Thanks for the feedback Dick.

Yes I can see why that happens - my previous “fix” was only a partial fix. This version should be properly fixed.
I should really rewrite this plug-in as the code has become quite messy, but it should work properly now.

I’ve only had time to test this on mono files and I’m on my way out now but I didn’t want to delay posting it, so it will need testing on stereo tracks.
popmute.ny (1.89 KB)

Here’s a before/after recording using the latest version of Pop Mute on a very nasty multiple click.

My immediate reaction was “good test”, but the old versions don’t do anything uncouth to this one either, at least with my settings. What were the settings for your demo?

Is there a generator plugin for that between-takes “beep”? I’ve seen another one posted on this forum in which the channels were phase-quadrature.