Eliminating dropouts

[sciurius]

After recording some audio streams I ended up with audio data that has frequent dropouts, short periods of time where there is no audio present. It seems to be a recording problem since simply removing the dropout results in good audio.
In Audacity, I use Analyze->Silence Finder to find the dropouts and Effect->Truncate Silence to remove each dropout. I can, however, not generally apply Truncate Silence to the whole recording since it also contains track gaps. So what I need is a Truncate Silence function that I can ask to remove all silences shorter than, say, 0.5 seconds.
From reading the Silence Finder source I think this cannot be hard to do except that I have no idea how. There's no nyquist source for Truncate Silence.
Suggestions are welcome.

[Trebor]

"Dropouts" = skipping ? ... http://wiki.audacityteam.org/index.php? ... ings#Skips

[sciurius]

Yes, I read that information some time ago and this could very well be the source of the problems.
However, I've already got several of these recordings that still needs fixing.

[kozikowski]

Behold the problem of posting in a generic forum.

Which Audacity are you using? I think the silence and sound finders in Audacity 1.3.12 may have such tuning tools.

Koz

[sciurius]

I have 1.3.12. The sound and silence finders are capable of doing what I want, but not in one single operation.
My current workflow is:
1. Find all silences <= 80db and longer than 0.01 seconds. This will find short silences (the dropouts) *AND* long silences (the track gaps).
2. Select small portions of the music just around where a silence was found, and kill the silence.

I cannot (or at least I have not found how to do that) select the whole track and remove the smaller silences without affecting the longer ones.

[kozikowski]

If you don't get any more good information here, I'm going to point you to the "Adding Features" portion of the forum.

http://forum.audacityteam.org/viewforum.php?f=20

Koz

[steve]

I cannot (or at least I have not found how to do that) select the whole track and remove the smaller silences without affecting the longer ones.

drop-outs (skips) are often extremely quiet (absolute silence, or very close to absolute silence).
If your track is in 32 bit format, try setting the silence finder threshold to a very low level. The lowest that you can get using the slider is -100dB, but if you type the number in you can go even lower. "Normal" silence between tracks is unlikely to be as low as -100 dB, but if you are lucky and the drop-outs are absolute silence, then by setting the silence finder threshold to, say, -120 dB, it will still pick up the drop-outs but miss the gaps between tracks.

[sciurius]

Excellent suggestion.
Unfortunately the intertrack gaps of my recordings are as quiet as the dropouts (tried up to -400db).
But this leads me to an alternative way to deal with the problem.
If it were possible to put the cursor in the middle of empty space and have Audacity fill it with (say) -200db noise then it would be rather straightforward to fill all track gaps with noise, then select the whole recording and remove all silences, killing the dropouts.