lengthen silences

[westwind]

effects - truncate silence is great and works well.

Is there an opposite though? - ie something which would automatically locate the silences and then increase them by a changeable percentage?

[Irish]

Almost.

Analyze > Silence Finder will locate silences and place a label at each one.
However, you will have to go through manually increasing the length of the silences.

PO'L

[steve]

However, you will have to go through manually increasing the length of the silences.

The quickest way to do that is to Generate silence for the first marker, then copy that silence (Ctrl+C). Once you have copied the silence, you can paste it by simply clicking where you want it at pressing Ctrl+V

[westwind]

I know I can do it manually, however that is not practical for the application I have in mind. (I have an audio version of the Bible - in 1189 files. I want to add a pause - ie a lengthened silence - after each phrase, therefore I want to add an estimated 25K pauses, therefore accomplishing this by using chains or similar is highly preferable!)

[steve]

How about burning to CD. Some CD burning programs (such as Nero) allow you to put silences of user defined length between each track (or you can pause the CD player). Most CD burning programs will insert a 2 second pause between tracks by default.

Limitations:
The maximum number of tracks on an audio CD is 99.

(I have an audio version of the Bible - in 1189 files.

Audacity cannot import multiple tracks one after the other (append import). Imported tracks are always one audio file per track (each new import is on a track below the previous one).

It seems like this feature request viewtopic.php?f=15&t=21595&p=67406#p67406 would provide what you want.

[westwind]

I don't want to lengthen silence after each track but more like after each sentence, or certainly after each verse. I'd have to experiment with choosing suitable parameters to detect the silence, but Audacity is already good at that.

Also I don't want to append - just want to process the 1189 files separately and export them as mp3 again (slightly lossy procedure I know) - so I'd be importing a file, lengthening say 10 to 200 silences and then exporting.

Thanks for your replies.

[waxcylinder]

Yes ok then: use the silence finder to identify the silences, this will create a whole slew of labels one for each silence. Then use Export Multiple to export a set of WAV files based on the silence-labels. Then as Steve suggest burn the CD with intertrack gaps of the required length.

The limitation that you are likely to run in to is one imposed by the Red Book standard for CDs in that the maximum number of tracks allowed on a CD is 99. To circumvent this just burn the CDs in cunks of 99 tracks - blank CD-Rs cost c. 10USc/10pUK - so getting through a stack of those will still be cheaper tahn your time.

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Out of curiosity: just why do you want a gap at the end of each biblical phrase?

WC

[westwind]

The 1189 tracks with current silences are 75hrs, so I think I'll keep looking rather than go down the CD route.

>Out of curiosity: just why do you want a gap at the end of each biblical phrase?

>WC

It is read at normal speed, but I'd like to try it with longer pauses for comprehension. I've tried the Change Speed effect in Audacity, but that doesn't sound too good.

I didn't know about Export multiple (thanks Steve) - or that it could split the track at each silence, so that is a good step forward. I just need a joiner now that will add silence at beginning or end.

[steve]

I've hacked the code of the Silence Finder plug-in so that it will insert additional silence instead of creating labels.
This is a "quick 'n' dirty" hack rather than a polished piece of code, so there are a few limitations:
1) probably requires Audacity 1.3.7 or later (only tested on 1.3.11)
2) quite memory hungry - applying to long tracks will probably crash Audacity. To ensure that used memory is released, restart Audacity.
3) mono tracks only.
(the "category" is also wrong, but this will not affect current versions of Audacity)

To see where silence will be inserted you can run "Silence Finder" first, then use the same settings for "Silence Lengthen"

To use, extract the attached file into your Audacity plug-ins directory. Restart Audacity and "Silence Lengthen" will appear in the Effects menu.

silencelength.ny.zip

(2.15 KiB) Downloaded 287 times

[westwind]

Wow that works! I just tried it on a 55 minute track and it handled that fine. Would I be able to incorporate it into a chain?? At the moment it shows up below the line near the bottom of effects and the ones there don't show up in the SELECT COMMAND window when editing a chain.

My application is probably a bit obscure, but I think this effect would be a very useful addition to Audacity for use in transcribing audio; I've often done that in the past and usually end up contstantly backtracking to get it right. I've also used change speed for that as well but to be able to lengthen silences would likely be a much better way to do it.