Hi All,
Heres a new application which Ive used on the recording.
First an example from the original recording (no changes) - then the isolat=
ed call extracted, followed by the original with some background noise remo=
ved and again the call on its own with more amplification. -Quite an easy t=
ask in spectral layers, see the tutorial file section on the website for mo=
re info.
http://urlme.net/audio/spectrallayers.mp3
The application web site:
http://www.divideframe.com/?p=3Dspectrallayers
Now to remove that generator humming away in my beech recording...
BR
Mike.
--- In 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 =3D 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%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%
> >>> 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
> >>>>
> >>
> >>
>
|