Dear Juan,
Thanks a lot. I would be happy to receive your pdf paper. 
Bye
Gary

>Hi,
>
>A FFT (actually a you need a windowed Fourier transform) won't have enough
joint time and frequency resolution at both high an low frequencies.
>A continuous wavelet transform could be used for the analysis, but it
can't reconstruct signals, so it can't be used if you want to rebuild the
different sounds. A discrete 
>wavelet transform won't have enough frequency resolution. So, it's an open
problem, and there is currently a lot on research on it. This very problem
has been my 
>obsession for the last couple of years, and I have just presented a paper
with new results on August at the SPIE's Wavelets-X conference in San
Diego. (I can send the 
>pdf file to any interested.)
>
>Of course, this is just the analysis and reconstruction of the signals, in
middle you need some sort of AI, fuzzy logic, neural nets or such to do the
actual separation of the 
>sounds.
>
>Cheers,
>Juan
>
>On Thu, 18 Sep 2003 14:18:21 -0500, Daniel Joyce wrote:
>
>>On Thursday 18 September 2003 11:40, Gary McGovern wrote:
>>> Thanks for all those links and resources. I'm more than surprised this
>>> isn't more evolved. I thought if the human ear could selectively pick
out a
>>> track in a composition / song then that track has its own unique state
and
>>> behavior and it would just be a matter of defining the state and
behavior
>>> and identifying those tracks electronically.
>>>
>>> Thanks again.
>>>
>>> Gary
>>>
>>
>>The problem is, music is the sum of all the frequency, harmonics, and
phase 
>>information in it.
>>
>>If I give you the number 100, can you tell what numbers I summed or
multiplied 
>>to arrive at that number? 100x1? 20x5? 4x20+20? It's impossible to tell,
the 
>>information is lost in the process. :)
>>
>>Now with music, that isn't entirely true. But, yer gonna need to do some
work. 
>>You're probably going to need to work in the Frequency domain ( so use a
FFT, 
>>or wavelet transform to get there ), and also, phase information ( a bit
more 
>>trickier ). Once you've got all that, it might be possible ( depending on

>>signal noise, etc ) to pick out one trumpet, and 'follow' it through the 
>>piece. You KNOW what a trumpet sounds like, but how do you tell the
computer 
>>that? ( Possibly, take a trumpet sample, and have it scan for a 'closest'

>>match in some fashion ).
>>
>>Turns out, the reason why it's easy for people to do it, to hear and
follow 
>>the trumpet piece in the symphony, is that some of the work is done by
the 
>>structure of the inner ear ( Different frequencies excite different areas
of 
>>the spiral shaped inner ear, so in essence, it's performing a Fourier 
>>transform ), and the brain is a massively parallel machine. 
>>
>>
>>The Meek shall inherit the Earth,
>>for the Brave are among the Stars!
>>
>>
>
>
>
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