Does what it says on the can....
http://www.urlme.net/blog/?p=1790
-Mike.
--- In "Mike Rooke" <> wrote:
>
> Hi All,
> Heres a new application which Ive used on the recording.
>
> First an example from the original recording (no changes) - then the isolated
> call extracted, followed by the original with some background noise removed
> and again the call on its own with more amplification. -Quite an easy task in
> spectral layers, see the tutorial file section on the website for more info.
>
> http://urlme.net/audio/spectrallayers.mp3
>
> The application web site:
>
> http://www.divideframe.com/?p=spectrallayers
>
> Now to remove that generator humming away in my beech recording...
>
> BR
> Mike.
>
> --- In vickipowys <vickipowys@> wrote:
> >
> > Peter,
> >
> > All your questions about the frogs are interesting ones and of course
> > I don't know the answers. Except to say I think it is just one frog
> > giving the calls.
> >
> > In my experience of living for 15 years in an area where there are
> > quite a few GT Frogs about, I had never heard this call before until
> > a couple of years ago, and it was a very long time before I was able
> > to get a recording. The call would occur briefly about once each
> > night during the summer. I kept microphones on my front verandah
> > because I was also doing some research on night birds. That way I
> > was eventually able to pick up a recording and much later tracked it
> > down to Green Tree Frog distress call.
> >
> > At one stage a small goanna got into my ceiling and ate some frogs,
> > but the frogs then gave a different sort of distress call, more of a
> > moaning shriek. I have picked up the frogs with my hands and they
> > make no sound at all, or maybe just a brief croak. It was only with
> > the mice attacking them that the frogs gave this shrill call. I
> > don't know why the frogs didn't simply hop away. I suppose the mice
> > just chased them and nipped at their feet until they could not hop
> > any more.
> >
> > I have also heard GT Frogs occasionally give a sharp yapping call.
> > Mostly of course they just give a loud and rhythmic croak-croak-croak
> > call, especially when it is hot and raining.
> >
> >
> > Vicki
> >
> >
> >
> > On 05/12/2011, at 8:52 AM, Peter Shute wrote:
> >
> > > OK, good, I hadn't noticed that parameter before, and it makes
> > > quite a difference. I do see the faint bands now. I'll sent Tom
> > > Tarrant the link to your sonogram, and he can decide for himself.
> > >
> > > Now I'm curious to know what was happening to the frog. And was it
> > > one frog, or a series of frogs being attacked by something one by
> > > one? I'm also curious to know why this call is apparently uncommon
> > > on Tom's recordings - I would have thought froggy death was a daily
> > > occurrence in that habitat. Perhaps it's normally too swift. (I'm
> > > not expecting any answers to these questions.)
> > >
> > > Peter Shute
> > >
> > > ________________________________
> > > From:
> > > On Behalf Of vickipowys
> > > Sent: Monday, 5 December 2011 8:12 AM
> > > To:
> > > Subject: Re: [Nature Recordists] Re: Advice needed for cleaning up
> > > this recording
> > >
> > >
> > >
> > > Peter,
> > >
> > > Yep, FFT = the sharpness setting in Raven Lite. In some applications
> > > it is called FFT (Fast Fourier Transform).
> > >
> > > Basically when you are adjusting any sonogram settings, you simply
> > > juggle the available settings until you get an image as clear as
> > > possible and that suits your needs. A less contrasty sonogram is
> > > more likely to show up some of the less obvious aspects of the
> > > sound. A more contrasty sonogram can be useful for publication,
> > > provided you already have a good clear sound to work with.
> > >
> > > I like to work with black and white (which is useful for publication)
> > > altho some members on this list prefer to work with colour for on
> > > screen analyses.
> > >
> > > For anyone using Izotope, the lovely sonograms that it produces can
> > > be set to white on black, but not black on white. But it is easy to
> > > invert the image using photoshop so that you get black on white. You
> > > need to take a screen shot of the Izotope screen first, to work with.
> > >
> > > Vicki
> > >
> > > On 05/12/2011, at 5:31 AM, Peter Shute wrote:
> > >
> > >> FFT? Where do I set that in Raven Lite? All I see is a third
> > >> adjustment called "sharpness".
> > >>
> > >> Peter Shute
> > >>
> > >> ________________________________
> > >> From: <naturerecordists%
> > >> 40yahoogroups.com>
> > >> <naturerecordists%
> > >> 40yahoogroups.com>] On Behalf Of vickipowys
> > >> [vickipowys@<vickipowys%40skymesh.com.au>]
> > >> Sent: Sunday, 4 December 2011 2:20 PM
> > >> To: <naturerecordists%
> > >> 40yahoogroups.com>
> > >> Subject: Re: [Nature Recordists] Re: Advice needed for cleaning up
> > >> this recording
> > >>
> > >>
> > >>
> > >> Peter,
> > >>
> > >> You are quite right to be suspicious of the effects filtering may
> > >> have on a sonogram. So let's go back to the original.
> > >>
> > >> If you look at the left hand channel of the original recording in
> > >> Raven Lite, with the settings at 50 darkness and 50 contrast, and FFT
> > >> size 2516, that may help. Expand the sonogram window so that you are
> > >> seeing about 1 minute of sound, and only up to 10 kHz, then you
> > >> should be able to see two more harmonic bands at around 3 khz and 2
> > >> khz for at least some of the calls. At 1 kHz things get messy
> > >> because of other things calling.
> > >>
> > >> In Sonic Visualizer, I could not find where to adjust the brightness
> > >> and contrast and FFT for the sonograms, and therefore could not get a
> > >> very clear result.
> > >>
> > >> Izotope RX gave a good result (but only very slightly better than
> > >> Raven Lite), i.e. just looking at the spectrogram window of the
> > >> original recording and adjusting the controls for clearest settings.
> > >>
> > >> You are right that normally it is the higher frequencies that are
> > >> attenuated by distance. In the case of the frog distress call
> > >> though, the strongest part of the call is not in the lowest
> > >> frequencies, but higher up, say above 3 kHz. So with Tom's call
> > >> being so faint in the first place, maybe the lower frequencies simply
> > >> did not pick up on the recording.
> > >>
> > >> Also, I don't know what other effects the mp3 format may have had on
> > >> the recording.
> > >>
> > >> cheers,
> > >>
> > >> Vicki
> > >>
> > >> On 04/12/2011, at 12:56 PM, Peter Shute wrote:
> > >>
> > >>> Interesting. I can see the same sonogram patterns using Raven and
> > >>> Sonic Visualiser using the track you just uploaded, but on the
> > >>> original and all other attempts at cleaning it up, the sub 4kHz
> > >>> bands aren't really visible. Even in yours, they're much fainter
> > >>> that those above 4.
> > >>>
> > >>> I agree it looks like a good match, and a very likely one too,
> > >>> given the location, but I'm wary of something that's completely
> > >>> invisible on the original.
> > >>>
> > >>> Sonograms are a new thing to me, so I'm right out of my depth here.
> > >>> Do you think the distance and reverb can explain why the lower
> > >>> harmonic bands are fainter? I would have thought higher frequencies
> > >>> would be attentuated by distance more than lower ones (but I'm not
> > >>> sure about that).
> > >>>
> > >>> Or perhaps they're just almost completely masked by the frog
> > >>> chorus, and would have to be fainter once that's removed. On closer
> > >>> inspection, I can see a faint band around 3kHz on the original in
> > >>> a couple of spots (eg 28s), but I just couldn't say below that.
> > >>>
> > >>> Peter Shute
> > >>>
> > >>> ________________________________
> > >>> From: <naturerecordists%
> > >>> 40yahoogroups.com><naturerecordists%
> > >>> 40yahoogroups.com>
> > >>> <naturerecordists%
> > >>> 40yahoogroups.com><naturerecordists%
> > >>> 40yahoogroups.com>] On Behalf Of vickipowys
> > >>> [vickipowys@<vickipowys%
> > >>> 40skymesh.com.au><vickipowys%40skymesh.com.au>]
> > >>> Sent: Sunday, 4 December 2011 11:25 AM
> > >>> To: <naturerecordists%
> > >>> 40yahoogroups.com><naturerecordists%
> > >>> 40yahoogroups.com>
> > >>> Subject: Re: [Nature Recordists] Re: Advice needed for cleaning up
> > >>> this recording
> > >>>
> > >>>
> > >>>
> > >>> Peter,
> > >>>
> > >>> I'm sorry you've given up on the mystery call. Here is one last
> > >>> attempt on my part to convince you the mystery call really is the
> > >>> distress call of a Green Tree Frog.
> > >>>
> > >>> I've selected just a short side-by-side comparison, using the
> > >>> clearest part of Tom's recording that I could find. I've also
> > >>> presented the recordings at half speed, which is always useful for a
> > >>> listening test.
> > >>>
> > >>> This is the soundcloud link:
> > >>>
> > >>> http://snd.sc/ticMjy
> > >>>
> > >>> I've included a Raven sonogram that shows how the harmonics,
> > >>> although
> > >>> faint, do extend well below 4 kHz (you thought they did not).
> > >>>
> > >>> I did some broad band noise reduction on Tom's original recording
> > >>> using RX, and removed the prominent insect call.
> > >>>
> > >>> cheers,
> > >>>
> > >>> Vicki
> > >>>
> > >>> On 03/12/2011, at 7:26 PM, Peter Shute wrote:
> > >>>
> > >>>> Thanks everyone for your attempts at cleaning up this recording.
> > >>>> We've given up on identifying the call for now. I assume it must be
> > >>>> a lesser known call that we have no samples of for comparison. We
> > >>>> had quite a few suggestions that sounded similar, but nothing with
> > >>>> a matching sonogram.
> > >>>>
> > >>>> Now I just have to try to understand the steps you all took so I
> > >>>> can try for myself next time.
> > >>>>
> > >>>> Peter Shute
> > >>>>
> > >>
> > >>
> >
>
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