Re: [music-dsp] Cheap spectral centroid recipe

Theo wrote: >I get there are certain statistical ideas involved. I wonder >however where those ideas in practice lead to, because >of a number of assumptions, like the "statistical variance" >of a signal. I get that a self correlation of a signal in some >normal definition gives an idea of the

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Ethan Duni" <ethan.d...@gmail.com> Date: Thu, February 25, 2016 4:16 pm To: "A discussion list for music-related DSP" <

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Esteban Maestre" <este...@ccrma.stanford.edu> Date: Thu, February 25, 2016 4:59 pm To: music-dsp@mu

Re: [music-dsp] Cheap spectral centroid recipe

Hi there, On 2/25/2016 3:57 PM, Evan Balster wrote: When working with tonal signals, it has been proposed that brightness be normalized through division by fundamental frequency. This produces a dimensionless (?) metric which is orthogonal to the tone's pitch, and does not typically fall

Re: [music-dsp] Cheap spectral centroid recipe

>Lastly, it's important to note that differentiation and semi-differentiation >filters are always approximate for sampled signals, and will tend to >exhibit poor behavior for very high frequencies and (for semi-differentiation) >very low ones. I'm not sure there's necessarily a problem at low

Re: [music-dsp] Cheap spectral centroid recipe

For my own benefit and that of future readers, I'm going to summarize the thread so far. The discussion here concerns metrics of "brightness" -- that is, the tendency of a given signal toward higher or lower signal content. The method proposed for analyzing brightness involves inspecting

Re: [music-dsp] Cheap spectral centroid recipe

Evan Balster wrote: ... To that end: A handy, cheap algorithm for approximating the power-weighted spectral centroid -- a signal's "mean frequency" -- which is a good heuristic for perceived sound brightness . In spite of its

Re: [music-dsp] Cheap spectral centroid recipe

In late 2013 (I think) I experimented with a preliminary implementation of the brightness articulation in my pitch tracking software. I normalized it based on fundamental frequency, which at the time seemed like common sense due to the mathematical elegance of a well-defined minimum. Since then

Re: [music-dsp] Cheap spectral centroid recipe

Robert, On Fri, Feb 19, 2016 at 3:38 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > geez, i wish i could cut and paste text without getting all of that HTML > crap in there. i dunno how this is going through majordomo or whatever > Douglas has running the list. That's a

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Risto Holopainen" <ebel...@ristoid.net> Date: Fri, February 19, 2016 7:45 am To: music-dsp@mu

Re: [music-dsp] Cheap spectral centroid recipe

On February 18, 2016 at 10:48:20 pm +01:00, Ethan Duni <> wrote: > I was kind of hoping someone would chime in with a reference to a publication > of some tests comparing different spectral centroid methods, showing how well > they match some subjective ratings of

Re: [music-dsp] Cheap spectral centroid recipe

From: "Ethan Duni" Date: Thu, February 18, 2016 4:48 pm -- > I've noticed > in my (cursory) searches that some people use amplitude spectra and others > use power spectra, but the only

Re: [music-dsp] Cheap spectral centroid recipe

gt; >>>> Yeah tonal signals open up a whole other can of worms. I'd like to >>>> understand the broadband case first, with relatively simple spectral >>>> statistics that correspond to the clever time-domain estimators discussed >>>> so far in the thread

Re: [music-dsp] Cheap spectral centroid recipe

eck of a lot more to my brightness perception > than adding the same amount of energy at 60Hz or 15kHz. > > -Ethan > > > > On Thu, Feb 18, 2016 at 3:08 PM, robert bristow-johnson < > r...@audioimagination.com> wrote: > >> >> >>

Re: [music-dsp] Cheap spectral centroid recipe

obert bristow-johnson < r...@audioimagination.com> wrote: > > > Original Message ---------------- > Subject: Re: [music-dsp] Cheap spectral centroid recipe > From: "Evan Balster" <e...@imitone.com> > Date:

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Evan Balster" <e...@imitone.com> Date: Thu, February 18, 2016 1:55 pm To: music-dsp@mu

Re: [music-dsp] Cheap spectral centroid recipe

spectral centroid you use. For the mean of the power >>> spectrum it seems relatively straightforward to get some tractable >>> expressions - I guess this is the inspiration for the one based on an >>> approximate differentiator. But I suspect that mean of the log power >>> spectru

Re: [music-dsp] Cheap spectral centroid recipe

aightforward to get some tractable >> expressions - I guess this is the inspiration for the one based on an >> approximate differentiator. But I suspect that mean of the log power >> spectrum is more perceptually meaningful. >> >> E >> >> On Wed, Feb 17,

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Evan Balster" <e...@imitone.com> Date: Thu, February 18, 2016 10:42 am To: music-dsp@mu

Re: [music-dsp] Cheap spectral centroid recipe

17, 2016 at 8:34 PM, robert bristow-johnson < > r...@audioimagination.com> wrote: > >> >> >> -------- Original Message >> Subject: Re: [music-dsp] Cheap spectral centroid recipe >> From: "Ethan Duni" <ethan.d..

Re: [music-dsp] Cheap spectral centroid recipe

om> wrote: > > > Original Message -------- > Subject: Re: [music-dsp] Cheap spectral centroid recipe > From: "Ethan Duni" <ethan.d...@gmail.com> > Date: Wed, February 17, 2016 11:21 pm > To: "A discussion list f

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Ethan Duni" <ethan.d...@gmail.com> Date: Wed, February 17, 2016 11:21 pm To: "A discussion list for music-related DSP" <

Re: [music-dsp] Cheap spectral centroid recipe

Original Message Subject: Re: [music-dsp] Cheap spectral centroid recipe From: "Ethan Duni" <ethan.d...@gmail.com> Date: Wed, February 17, 2016 11:21 pm To: "A discussion list for music-related DSP" <

Re: [music-dsp] Cheap spectral centroid recipe

>It's essentially computing a frequency median, >rather than a frequency mean as is the case >with the derivative-power technique described > in my original approach. So I'm wondering, is there any consensus on what is the best measure of central tendency for a music signal spectrum? There's the

Re: [music-dsp] Cheap spectral centroid recipe

Dario's adaptive approach is interesting. It's essentially computing a frequency median, rather than a frequency mean as is the case with the derivative-power technique described in my original approach. Dario, I would suggest experimenting with zero-phase FIR filters if you're doing offline

Re: [music-dsp] Cheap spectral centroid recipe

This reminds me a bit of the voiced / unvoiced detection for vocoders or level independent de-essers. It works quite well. Steffan > On 17.02.2016|KW7, at 13:08, Diemo Schwarz wrote: > >>1. Apply a first-difference filter to input signal A, yielding signal B.

Re: [music-dsp] Cheap spectral centroid recipe

BTW, did you check COBE G. Presti and D. Mauro, “Continuous brightness estimation (cobe): Implementation and its possible applications,” in 10th International Symposium on Computer Music Multidisciplinary Research (CMMR). Laboratoire de Me ́canique et d’Acoustique, 2013, pp. 967–974. and

Re: [music-dsp] Cheap spectral centroid recipe

Hello everybody. First post for me too. I don't have a technical or mathematical background so I will just be sharing what this very simple idea is. A few months ago I came out with this rudimentary brightness estimator based on two first-order recursive filters, one high-pass and one low-pass,

Re: [music-dsp] Cheap spectral centroid recipe

Oriol Romani Picas pointed out a few errors in my implementation of the algorithm above. Thanks, Oriol! Specifically, in step 4, the *square root* of PB/PA -- effectively an RMS -- is used, and we multiply by the sampling rate divided by two pi. The example code

Re: [music-dsp] Cheap spectral centroid recipe

Exactly. See also http://www.audiocontentanalysis.org/code/audio-features/spectral-centroid/ Alexander On 2016-02-01 17:24, robert bristow-johnson wrote: > well, i remember a paper from long ago from James Beauchamp where he > defines spectral centroid as > > > > SUM{ |c_n| n } / SUM{

Re: [music-dsp] Cheap spectral centroid recipe

well, i remember a paper from long ago from James Beauchamp where he defines spectral centroid as � � SUM{ |c_n| n } / SUM{ |c_n| } � where c_n is the complex Fourier coefficient for the nth harmonic. �if you wanted to base it on energy � � SUM{ |c_n|^2 n } / SUM{ |c_n|^2 } � it will

Re: [music-dsp] Cheap spectral centroid recipe

> > Evan Balster > creator of imitone so Evan, i took a look at your website. �your product looks very cool. �in 2013 i worked on something similar (Zya), but cloud based. � so you clearly have a pitch detector goin' on there. �are you converting vocal pitch into fully

Re: [music-dsp] Cheap spectral centroid recipe

Robert -- Yeah, a DC offset spells trouble for my algorithm -- but it's nothing a bit of gentle pre-filtering (or a sane ADC) won't solve. I'll discuss the tangental stuff with you off-list where it doesn't go into hundreds of inboxes. :) – Evan Balster creator of imitone