[LAD] Determining Phase

[pshirkey at boosthardware.com]

> On Sat, 25 Jun 2011 16:23:29 +0200 (CEST), pshirkey at boosthardware.com
> wrote:
>> Hi,
>>
>> Can anyone point me to a simple code example for how to determine the
>> phase at a specific time in a waveform?
>>
>> ex. if I have a sample that is 5 seconds long and want to know the
>> phase
>> at 2.5 seconds
>>
>> I'm open to code in any language or a scripted example if such a tool
>> exists. If there is an ui which has that feature I am also
>> interested.
>>
>
> in general, theory i mean, phase equals delay; it can be computed
> deterministically iif the signal is a pure tone (sinusoidal) otherwise
> you must have a reference signal and referring to its fundamental
> frequency (1st order harmonic) or, when in-the-field, you can pick one
> conventional signal tone (i've been told that a 1khz is a usual choice:)
> and compare to that.
>
> if you are to compare two known signals (often input vs. output of some
> lti transformation, eg. filter), than the computation to do is
> correlation. well, you should use fft for that, but i'm sure you know
> that:)
>

You wouldn't happen to have an example of this code?

Perhaps there is something in qtractor along these lines already?

I have looked at integrating something with librubberband but first things
first right?



--
Patrick Shirkey
Boost Hardware Ltd