Re: About importance of "phase" in sound recognition

[Laszlo Toth <tothl@xxxxxxxxxxxxxxx>]

On Thu, 7 Oct 2010, ita katz wrote:

> I think that the distinction between signals which have or do not have phase
> is not binary - it is a gradual transition between the two, since the
> question 'when is a signal (semi) periodic?' does not have one answer, not
> mathematically and not psychoanalytically - A sinosuid of .5 a period is
> clearly not periodic, but a sinosuid of 100 periods clearly is - where is
> the transition between the 'periodic' and 'non-periodic'? it is not a
> point-transition.

Matematically a function f is periodic if f(x)=f(x+p) for some p>0 for ALL
values of x. So _mathematically_ your argument is clearly incorrect.
It is another thing that I understand your argument and admit that it
would make sense to have same more practical, "pschychoacoustic"
definition of "periodic" and "phase". But my feeling is that such a
definition does not exist, and this causes confusion.

               Laszlo Toth
        Hungarian Academy of Sciences         *
  Research Group on Artificial Intelligence   *   "Failure only begins
     e-mail: tothl@xxxxxxxxxxxxxxx            *    when you stop trying"
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