I have an audio file that has about 110 milliseconds of silence (pure silence) every minute or so. Can I use audacity to remove all of these at once (so I don’t have to find and delete hundreds of these silences)?
Thanks,
David
It would however be better to find and fix the cause of the skips. See Managing Computer Resources and Drivers - Audacity Wiki .
Gale
Thanks kozikowski. I thought that the Truncate Silence effect might be what I was looking for too but when I tried it, it did not seem to remove any of the moments of silence (I set the length range from 80 ms to 150 ms which definitely includes all the silences I looked at manually). Maybe truncate silence only cuts silence from the beginning or ending of a clip or selection. I set the ratio really high so it should have almost entirely removed the silence (there is apparently no option to fully remove the silence with truncate silence, only shrink it).
Thanks for joining in the thread Gale Andrews. In my searching before posting I saw that the direction you are suggesting is the way all the similar threads (about skips) on this forum turn. I agree that if you can fix the problem that led to the skips that would be ideal but that is not an option here (I downloaded the file from the internet and did not produce it myself). I was asking if Audacity was capable of removing these. It seems like the algorithm to do this would be pretty simple (scan waveform/array for period of pure silence lasting more than some lower threshold entered by the user, then delete all of those samples in the contiguous block of zeros) so I would be surprised if nobody has ever written it before.
I said the little silences occurred every minute or so but there are actually 2 to 3 each minute of a 120 minute file (so it would be real pain to have to delete all of them by hand).
Thanks,
David
There is no range so I think you are interpreting min silence and max silence incorrectly (which is 100% forgiveable as the labels for that effect are too cryptic). Truncate Silence will have a much better interface in 2.0.6 when released.
Have a look at Truncate Silence - Audacity Manual . Try setting min to 80 and max to 1. If you are not getting enough truncation, increase the threshold.
Gale
Thanks Gale, I definitely misunderstood that max duration value. I tried a min duration of 80 ms and max duration of 1 ms and the effect still removed none of the silences throughout the audio clip (and no apparent reduction in duration either). since I want to fully remove the silences I wish I could put zero in the max duration field but that is not allowed. I also tried a max duration of 100 ms and still none of the silences were removed or reduced.
Audacity 2.0.6 is due to be released soon, and in that version you will be able to truncate silences to zero.
Don’t set the threshold to the minimum setting (-80 dB). Due to a bug in the current version, that setting doesn’t work (it disables the effect if I recall correctly). This has also been fixed in the new version. The minimum threshold that works is -75 dB.
At the bottom of the Audacity home page (http://audacityteam.org/) you can enter your e-mail address and you will be notified when the next version is released.
And I can confirm that works very well.
As Steve knows I spent some time recently manually removing small gaps from a webcast - before I remembered that the alpha 2.0.6 version of Truncate Silence would do it for me automatically and quickly .
You can download the latest alpha nightly from Gale’s site: gaclrecords.org.uk
If you are wary of using alpha software use 2.0.5 for the rest of the work - close the project, open it in 2.0.6 alpha, process the gaps - then close the project and re-open in 2.0.5.
But 2.0.6 alpha is pretty stable, closish to release - I have been living on the bleeding edge for a while now using it for all my production work (in the name of QA testing).
WC
Awesome! Thank you both!
I downloaded the version from today and it really worked like a charm, thank you so much for your help! In the case of this one file it turned out that some of the small silences/skips had momentary micro-noises in the middle of them so I had to experiment with the dB threshold a little.