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Re: Raven Lite

Subject: Re: Raven Lite
From: "Michael Dalton" mdaltonarielle
Date: Fri Nov 11, 2011 9:11 am ((PST))
RE: "A question I'm trying to answer is, can you easily distinguish between=

an original bird call and an imitation of that call eg by a lyrebird ie
does the call just sound the same to us (and have a different sonogram)
or are the sonograms virtually the same as well?"
=A0
Ian, looks like we are running parallel questions. I've been researching sp=
eech by talking birds and find people can't understand their own language (=
English) spoken by a bird even if the words are clear. It seems to be that =
bird owners do not understand free speech by their birds. When people send =
me clip and I transcribe them they are flabbergasted!
=A0
While a bit out of my area of knowledge, I will predict that people will NO=
T perceive the differences between two variations of a call. The only one y=
ou will find who can do it is a person who have extensive experience in LIS=
TENING to the types of sounds you are dealing with. It might be a handful o=
f people in the world. My speech investigations show how poor people are wi=
th the familiar, English, words.
=A0
The idea of sonograms is to view parts of the spectra of bird signals that =
we can't begin to resolve in the time domain. I think any program that prod=
uces sonograms will be useful.
=A0
There are a couple of autocorrelation programs that might fit with you work=
 as well. I did an autocorrelation that came up with a number between 0.28 =
and .40 (words spoken my macaw and me)=A0and I was disappointed. One day I =
did a correlation for the voice of a famous parrot and its trainer and foun=
d the figure was as low or lower than what I had determined.
=A0
My opinion is that there is no substitute for a trained listener, even if y=
ou have to practice to resolve signals 4 times faster than normal.
=A0
Mike
Florida
www.ParrotSpeech.com
=A0
=A0
=A0
Message: 1a.
Subject: 
Re: Raven Lite
Posted by:      "Ian Martin"   irmartinau
Thu Nov 10, 2011 3:20 pm        (PST)


Hi Peter,

Raven Lite will not only take a number of digitally recorded formats
from you recorder via a computer, but also read calls from any
commercial CD and hence you can supplement the disk provided with the
book, with Oz recordings eg the BOCA set or the sets by Fred van Gessel
etc. The book's CD has its main use with the examples used in the book,
allowing you to listen to and (using Raven Lite) simultaneously observe
the sonograms while you read the comments. The book and CD by the way is
not meant to be a sonogram based catalogue of US bird calls but rather
it is a collection of those calls which are described in the book and
form parts of the authors research over the years.
IMHO the main use of the book is to give you ideas about some of the
uses of bird call sonograms.

If you access to them the HANZAAB books have (very small) sonogram
examples with many species - but be aware - some birds only have one of
two different calls (eg Eastern Whipbird) but others have literally
thousands of variations (see the book) ... and some calls can also
change with time and with interactions with other birds.

A question I'm trying to answer is, can you easily distinguish between
an original bird call and an imitation of that call eg by a lyrebird ie
does the call just sound the same to us (and have a different sonogram)
or are the sonograms virtually the same as well? This has a practical
application with bird surveys using recorded sounds. At present a group
associated with the Hunter Bird Observers Club (HBOC) is monitoring some
rufous scrub birds using specialised waterproof recorders which can
record for days or even weeks unattended in the rainforest. RSB's are
easy to detect when they use their own characteristic chipping calls etc
but they also mimic other bird calls and sounds at times - is the
recording an RSB mimic or the real bird?

Ian
-----
Ian Martin        Newcastle,   NSW,   Australia









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