Hi everyone,
i wondered if someone made a patch measuring the PHASE of a reference signal compared to measured signal
and also if someone made a patch measuring the IMPULSE RESPONSE of a reference signal compared to measured signal
greetz Ck
For impulse response there is this:
http://cnx.org/content/col10519/latest/
Not fully explored this yet but it has been on my todo-list for too long...
Cheers,
Jb
On 4 November 2010 10:34, Christoph Kuhr christoph.kuhr@web.de wrote:
Hi everyone,
i wondered if someone made a patch measuring the PHASE of a reference signal compared to measured signal
and also if someone made a patch measuring the IMPULSE RESPONSE of a reference signal compared to measured signal
greetz Ck
Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Hi,
On Thu, Nov 04, 2010 at 11:34:27AM +0100, Christoph Kuhr wrote:
i wondered if someone made a patch measuring the PHASE of a reference
signal compared to measured signaland also if someone made a patch measuring the IMPULSE RESPONSE of a
reference signal compared to measured signal
I'm not sure what you mean by IR or phase of a "signal", usually it's some kind of transformation system like a filter, whose IR or PR people are interested in.
Anyway for measuring filter phase and frequency responses, the filter-graph abstractions in the Pd docs can be useful. Check out for example H10.measurement.pd and replace the [bp~] with whatever you would like to measure. It's using a swept-sine method.
Pure Measurement is a complete toolkit written in Pd for these kinds of things: http://www.hoertechnik-audiologie.de/downloads/PureMeasurement/
Ciao
Frank Barknecht Do You RjDj.me? _ ______footils.org__
Hi everyone,
i wondered if someone made a patch measuring the PHASE of a reference signal compared to measured signal
Hi,
you could one of the cross-correlation externals to measure the time delay between 2 signals. (there's one external in iem_tab from pd-extended I remember and there are possibly more). If that's useful for you I created a similar, fft based patch using vanilla objects I can post here.
However correlation doesn't directly measure phase differences of separate frequency bands but the delay of the signal over all frequencies.
Martin
On Thu, 4 Nov 2010, Martin Schied wrote:
Hi everyone, i wondered if someone made a patch measuring the PHASE of a reference signal compared to measured signalyou could one of the cross-correlation externals to measure the time delay between 2 signals. (there's one external in iem_tab from pd-extended I remember and there are possibly more). If that's useful for you I created a similar, fft based patch using vanilla objects I can post here. However correlation doesn't directly measure phase differences of separate frequency bands but the delay of the signal over all frequencies.
What do you mean ? If you get the imaginary part of the logarithm of the cross correlation, it gives you a list of phase differences corresponding to each frequency bin, right ?
(that's equal to the atan2 between the real and imaginary parts of the cross-correlation)
| Mathieu Bouchard ------------------------------ Villeray, Montréal, QC
i want to display it like the picture attached...
Am 04.11.2010 16:14, schrieb Mathieu Bouchard:
On Thu, 4 Nov 2010, Martin Schied wrote:
Hi everyone, i wondered if someone made a patch measuring the PHASE of areference signal compared to measured signal
you could one of the cross-correlation externals to measure the time delay between 2 signals. (there's one external in iem_tab from pd-extended I remember and there are possibly more). If that's useful for you I created a similar, fft based patch using vanilla objects I can post here. However correlation doesn't directly measure phase differences of separate frequency bands but the delay of the signal over all frequencies.
What do you mean ? If you get the imaginary part of the logarithm of the cross correlation, it gives you a list of phase differences corresponding to each frequency bin, right ?
(that's equal to the atan2 between the real and imaginary parts of the cross-correlation)
| Mathieu Bouchard ------------------------------ Villeray, Montréal, QC
On 04.11.2010 16:14, Mathieu Bouchard wrote:
On Thu, 4 Nov 2010, Martin Schied wrote:
Hi everyone, i wondered if someone made a patch measuring the PHASE of areference signal compared to measured signal
you could one of the cross-correlation externals to measure the time delay between 2 signals. (there's one external in iem_tab from pd-extended I remember and there are possibly more). If that's useful for you I created a similar, fft based patch using vanilla objects I can post here. However correlation doesn't directly measure phase differences of separate frequency bands but the delay of the signal over all frequencies.
What do you mean ? If you get the imaginary part of the logarithm of the cross correlation, it gives you a list of phase differences corresponding to each frequency bin, right ?
if your's still in the frequency domain you can do such things, but the iem_tab external output is already time domain - also I'm no math guru so you definitely answer this better... I took the math from http://www.engr.udayton.edu/faculty/jloomis/ece561/notes/xcorr/xcorr.html which is offline now unfortunately, but the explanation was very good. hope it comes back. ;)
(that's equal to the atan2 between the real and imaginary parts of the cross-correlation)
attached a correlation and a "phase difference" patch. it's very basic and may contain errors ;)
Martin
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Christoph Kuhr -
Frank Barknecht -
J bz -
Martin Schied -
Mathieu Bouchard