Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
gt;> Phew, thank you for confirming that! We use it in several products. >> >> Cheers, >> >> Steffan >> >> On 24.06.2020|KW26, at 17:07, Corey K wrote: >> >> But the end result i

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
(when I say satisfy the left hand side, I mean make the sum of shifted windows add up to a constant) On Wed, Jun 24, 2020 at 12:37 PM Corey K wrote: > Regarding e.q 4.5 it is easy to satisfy the left hand side of that > equation exactly (which is all that is needed) -- any COLA window w

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
les with M filter samples, the result is L= > N+M-1. So, if you use an FFT with size L, you can use M-1-L input samples. > So you need to zero-pad to avoid artefacts. > > Best, > > Steffan > > On 24.06.2020|KW26, at 16:10, Corey K wrote: > > I think you're mistake

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
cy response artifact no matter how small. It should > factor into the math in some way, perhaps they are not looking at the > laplacian > > On Wed, Jun 24, 2020, 10:41 AM Corey K wrote: > >> It's a classic paper. Google scholar shows it has been cited over 1000 >> time

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
;> wrote: >> >>> that's not true. with FFT/COLA you will necessarily have the Gibbs >>> phenomenon / ringing / ripple artifacts. certain window types will >>> minimize this but you will get this phenomenon nonetheless. >>> >>> On Wed, Jun

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
inimize this but you will get this phenomenon nonetheless. > > On Wed, Jun 24, 2020 at 9:44 AM Corey K wrote: > >> I see what you're getting at, I suppose. However, in the context of FIR >> filtering I wouldn't refer to this as an artifact. Let's say you gave m

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
tml > > i'm not referring to any equivalency between time/freq domain filtering > > > On Wed, Jun 24, 2020 at 9:21 AM Corey K wrote: > >> Not totally understanding you, unfortunately. But if what you are >> describing is part of the normal filter response/ringing

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
t? On Wed, Jun 24, 2020 at 10:02 AM Zhiguang Eric Zhang wrote: > yes but any windowing operation is akin to taking a dirac delta function > on X number of samples and thus you will get ringing/ripple artifacts as a > necessary part of the filter response > > On Wed, Jun 24,

Re: [music-dsp] Sliding Phase Vocoder (was FIR blog post & interactive demo)

2020-06-24 Thread Corey K
> of course it won't have the ripple artifacts associated with FFT overlap > windowing > What is the ripple artifact you are talking about? When using constant overlap add (COLA) windows the STFT is a perfect reconstruction filterbank. Likewise block FFT convolution can be used to implement any FI

Re: [music-dsp] Real-time pitch shifting?

2018-05-21 Thread Corey K
"Phase Vocoder Done Right" is a fairly interesting new paper I came across, that talks about a strategy to preserve both vertical and horizontal phase coherence. Examples (which sound pretty good) and link to paper are here: http://ltfat.github.io/notes/050/ -Corey On Mon, May 21, 2018, 06:46 Chr

Re: [music-dsp] (Novel?) "Modal Phase Rotation Synthesis"

2018-04-03 Thread Corey K
is that > you can cancel the internal state with an impulse. > > I havent figured out what the best excitation signal is. > > The paper you linked suggests to delay the impulse until a zero crossing > but that is not an option in my use cases. > > Am 03.04.2018 um 01:46 schrie

Re: [music-dsp] (Novel?) "Modal Phase Rotation Synthesis"

2018-04-02 Thread Corey K
Your idea seems to bear a few similarities to this (just in case you haven't seen it already): https://ccrma.stanford.edu/~jos/smac03maxjos/ On Mon, Apr 2, 2018 at 2:46 PM, gm wrote: > > I don't know if this idea is new, I had it for some time but have never > seen it mentioned anywhere: > > U

Re: [music-dsp] tracking drum partials

2017-07-30 Thread Corey K
ld be > interesting if your drums can change their resonant modes over time, as > happens with the tabla, timpani and others. > > Best, > Ian > > On Sun, Jul 30, 2017 at 12:14 PM, Corey K wrote: > >> You might want to look into a parametric method of estimating the

Re: [music-dsp] tracking drum partials

2017-07-30 Thread Corey K
You might want to look into a parametric method of estimating the partials as well, e.g., Prony's method, which could give you much higher resolution than the FFT. Best, Corey Kereliuk www.reverberate.ca On Jul 28, 2017 12:47 PM, "Thomas Rehaag" wrote: see below. > --

Re: [music-dsp] Oversized FFT windows --- why so little literature?

2016-08-27 Thread Corey K
I'm not sure how using IIR filters would improve latency? You still have to worry about the duration of the filters transient response, no? There are also the matters of 1) perfect reconstruction; and, 2) subsampling that are often important considerations On Sat, Aug 27, 2016 at 12:08 AM,

Re: [music-dsp] Oversized FFT windows --- why so little literature?

2016-08-24 Thread Corey K
It's not done because it causes time-domain aliasing. You can think of the DFT (or FFT) as a sampled version of the continuous frequency DTFT. If the samples aren't dense enough, you get aliasing in the dual domain (the time-domain in this case). This aliasing can be perfectly cancelled during synt

Re: [music-dsp] Time-domain noisiness estimator

2016-02-22 Thread Corey K
I don't have any links on the use of autocorrelation in this context, and I don't even know if it would work. My basic thought, however, was that the autocorrelation of white noise should be zero at all time lags other than 0. Pitched signals, on the other hand, should have peaks at multiples of th

Re: [music-dsp] Time-domain noisiness estimator

2016-02-21 Thread Corey K
I haven't researched this at all, so take the following with a grain of salt. But, how about looking at different features of the auto-correlation (e.g., flatness, peakiness, ...)? On Fri, Feb 19, 2016 at 1:49 PM, Dario Sanfilippo < sanfilippo.da...@gmail.com> wrote: > Hello everybody. > > Follow

[music-dsp] Audio freelance and consulting

2015-05-19 Thread Corey K
Hello music dsp list, I have started a side-business as an independent audio consultant and freelance developer. If there is anyone needing help with their audio software development, signal processing, machine learning, or sound design, please get in touch. My website has more information and so