Tom says they do record in wav format. I'll post a link as soon as I can ge=
t the original recording.
Peter Shute
From: =
.com] On Behalf Of vickipowys
Sent: Tuesday, 6 December 2011 10:23 AM
To:
Subject: Re: [Nature Recordists] Re: Advice needed for cleaning up this rec=
ording
Hi Mike,
My understanding is that the tt98_edit mp3 recording IS the
original. It comes from a Queensland University automatic recorder
used for wildlife surveys. I am guessing that it records in mp3
format, given that it would be running for long periods of time.
Needs Peter Shute or Tom Tarrants to verify this though.
This was the original link and request that Peter gave, which leads
you to the tt98 file:
> Those of you who also subscribe to birding-aus will already heave
> seen Tom Tarrant's request for help with identifying the bird
> chattering in the background of this recording:
> http://www.aviceda.org/audio/?p=3D208
>
> The problem is that the call is distant and masked by frog and
> insect calls. Can anyone suggest techniques for cleaning it up to
> make the call clearer?
>
> I tried high pass (>4000Hz) in Audacity, but it didn't clean it up
> enough. I repeated it a couple of times, and it was much cleaner,
> but sounded odd. I tried noise removal, which I'v never used
> before, using a quieter part of the track as a sample, and that
> sounded really odd.
>
> The call can be heard several times during the 1m20s recording, and
> a sonogram easily shows their location. Tom has provided a sample
> sonogram on that page.
>
> Peter Shute
It would be interesting Mike if you could try Spectral Layers again,
bearing in mind that we would like to keep all the harmonics below 4
kHz.
I found I could remove the insect whine just below 4 kHz using a VERY
narrow horizontal selection in RX, and Edit/ Silence selection. RX
normal version works fine on my Mac OSX 10.4.
What version of Spectral Layers are you using?
cheers,
Vicki
On 06/12/2011, at 9:45 AM, Mike Rooke wrote:
> Hi Vicki,
> If theres the original material somewhere I can run it
> though spectral layers to give some idea of what its capable of.
> (the linked url was already processed?)
>
> Ive found its far more stable than RX2 which didnt work very well
> on my machine. Im using the Pro version. The trial is too limited
> to be of much use. Most users would like to evaluate in stereo and
> at least to 44.1Khz.
>
> The app works like a photo editor with layers, you can copy
> spectral sections reposition them elsewhere in a new layer (to add
> noise back to an area you subtracted). The frequency tool is
> perhaps the most useful if a vocalisation needs to be extracted. It
> has some robotic sounding issues when using the noise gate although
> its possible to go in and manually brush over spectral areas (with
> fine resolution and amplitude tolerance).
>
> BR
> Mike.
>
>
> --- In <naturerecordists%40yahoogr=
oups.com>, vickipowys
> <> wrote:
>>
>> Hi Mike,
>>
>> The only problem with your example is that we were trying to show the
>> harmonics below 4 kHz (on the original they are just visible for at
>> least some of the calls), and your example seems to have wiped them
>> all away.
>>
>> Spectral Layers looks good as a noise reduction application though,
>> but pricey, $700 - $2200, yikes! I like the way it could remove the
>> background siren in the demo recording on their website.
>>
>> Vicki
>>
>>
>>
>> On 06/12/2011, at 3:20 AM, 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=3Dspectrallayers
>>>
>>> Now to remove that generator humming away in my beech recording...
>>>
>>> BR
>>> Mike.
>>>
>>> --- In <naturerecordists%40yahoo=
groups.com>, 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: <naturerecordists%40yaho=
ogroups.com>
>>>>> <naturerecordists%40ya=
hoogroups.com>] On Behalf Of vickipowys
>>>>> Sent: Monday, 5 December 2011 8:12 AM
>>>>> To: <naturerecordists%40yahoog=
roups.com>
>>>>> 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%40yah=
oogroups.com><naturerecordists%
>>>>>> 40yahoogroups.com>
>>>>>> <naturerecordists%40yahoogro=
ups.com><naturerecordists%
>>>>>> 40yahoogroups.com>] On Behalf Of vickipowys
>>>>>> [vickipowys@<vickipowys%40skymesh.com.au>]
>>>>>> Sent: Sunday, 4 December 2011 2:20 PM
>>>>>> To: <naturerecordists%40yahoo=
groups.com><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%40ya=
hoogroups.com><naturerecordists%
>>>>>>> 40yahoogroups.com><naturerecordists%
>>>>>>> 40yahoogroups.com>
>>>>>>> <naturerecordists%40yahoogr=
oups.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%40yaho=
ogroups.com><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
>>>>>>>>
>>>>>>
>>>>>>
>>>>
>>>
>>>
|