[aubio-user] Offset detection

[Lukasz Tracewski]

Hi Paul,

Thanks for the prompt answer.

I am trying to make a freeware software for identification of bird calls in noisy conditions. One of critical points in the task is to correctly identify "audio feature" (e.g. a bird call). As you can imagine length of a call is not fixed and distance from onset to onset in not necessarily call length. That is why I am looking for offset detection mechanism. 

If I need to retrieve both onset and offset, should I then use aubionotes instead of aubioonset?


Cheers,
Lucas

On 04/01/14, Paul Brossier  <piem at piem.org> wrote:
> On 04/01/2014 06:00, Lukasz Tracewski wrote:
> >Hi,
> >
> >Aubio has a plethora of great onset detection methods. How about offset
> >detection? I can imagine that running algorithm on reverse-ordered data
> >should provide me with offsets, but maybe there is a smarter approach
> >that I am missing.
> 
> Hi Lukasz,
> 
> There is no offset detection method in aubio (yet). The onset detection
> functions will sometimes peak during the transient sound created by the
> release of a note, but these peaks are expected be small compared to the
> ones produced by note onsets.
> 
> So far, offsets times are assumed to be where the level of the signal
> drops under a given threshold. aubionotes for instance uses a simple
> silence gate to determine the end of notes.
> 
> What kind of offsets are you looking at? Do you have a specific
> algorithm in mind?
> 
> There is the work of Emmanouil Benetos and Simon Dixon, who use a Hidden
> Markov Model to determine whether a pitch track is active or not:
> 
> http://www.eecs.qmul.ac.uk/~simond/pub/2011/Benetos-Dixon-ICASSP2011.pdf
> 
> Best, Paul
> 
> 
> >
> >Thanks,
> >Lucas
> >
> >
> >_______________________________________________
> >aubio-user mailing list
> >aubio-user at aubio.org
> >https://lists.aubio.org/listinfo/aubio-user
> >
> 
> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.aubio.org/pipermail/aubio-user/attachments/20140106/a93eef82/attachment.html>