Re: [music-dsp] up to 11

2016-06-21 Thread Evan Balster
n? Can the minimum degree of distortion (as expressed by some admissible metric thereof) be bounded as a function of N? Has anyone experimented with algorithms that achieve this through adaptive phase shifting or other means? – Evan Balster creator of imitone <http://imitone.com> On Tue,

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-09 Thread Evan Balster
HRC> has been updated to reflect this. Apologies for the misinformation and any confusion it might have caused -- I was referencing a very different implementation of the algorithm when writing the original post. – Evan Balster creator of imitone <http://imitone.com> On Tue, Feb 2, 2016

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-01 Thread Evan Balster
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 <http://imitone.

[music-dsp] Cheap spectral centroid recipe

2016-02-01 Thread Evan Balster
his is useful to somebody! I've certainly gotten quite a lot of mileage out of it. Evan Balster creator of imitone <http://imitone.com> ___ dupswapdrop: music-dsp mailing list music-dsp@music.columbia.edu https://lists.columbia.edu/mailman/listinfo/music-dsp

Re: [music-dsp] Tip for an audio resampler library doing cubic interpolation

2016-02-24 Thread Evan Balster
A note to Kjetil and future readers: Bear in mind that using code derived from JUCE source in a non-opensource application may be a transgression of the GPL license under which the original code is offered! (Unless you've purchased a commercial license to JUCE) – Evan Balster creator of imitone

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-25 Thread Evan Balster
ental frequency. This produces a dimensionless (?) metric which is orthogonal to the tone's pitch, and does not typically fall below a value of one. Whether such a metric corresponds more closely to brightness than the spectral centroid in hertz depends on a psychoacoustics question: Do huma

Re: [music-dsp] Tip for an audio resampler library doing cubic interpolation

2016-02-22 Thread Evan Balster
nput chunk. This is an outdated version of my resampler and it has various minutiae worthy of criticism -- with the most glaring being a lack of antialiasing. I supplied it here because it gets the job done and my current implementation relies on a rather large body of filter design code for Chebychev-II antialiasin

Re: [music-dsp] Tip for an audio resampler library doing cubic interpolation

2016-02-22 Thread Evan Balster
tively straightforward as reference code or a basis for your own adaptation. – Evan Balster creator of imitone <http://imitone.com> On Mon, Feb 22, 2016 at 11:08 AM, Kjetil Matheussen < k.s.matheus...@gmail.com> wrote: > > > On Mon, Feb 22, 2016 at 5:38 PM, Kjetil Matheussen &

Re: [music-dsp] Tip for an audio resampler library doing cubic interpolation

2016-02-22 Thread Evan Balster
settings propagation, and that's easily solved with standard data structures. – Evan Balster creator of imitone <http://imitone.com> On Mon, Feb 22, 2016 at 8:52 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > > >

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-17 Thread Evan Balster
music analysis. This would allow you to iteratively refine your median "in-place" for different points in time. – Evan Balster creator of imitone <http://imitone.com> On Wed, Feb 17, 2016 at 7:52 AM, STEFFAN DIEDRICHSEN <sdiedrich...@me.com> wrote: > This reminds me a bit

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-18 Thread Evan Balster
t next opportunity I should post up some code describing how to compute higher moments with the differential brightness estimator. – Evan Balster creator of imitone <http://imitone.com> On Thu, Feb 18, 2016 at 1:00 AM, Ethan Duni <ethan.d...@gmail.com> wrote: > >normalized

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-18 Thread Evan Balster
ecause it will be a long time before the perceptual properties of any brightness metric can be clearly understood, I'll stick to formulas whose mathematical properties are transparent -- these lend themselves infinitely better to being small pieces of larger systems. – Evan Balster creator of imitone

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-18 Thread Evan Balster
metric involving an "unpinking filter" and it works as you describe. That's the "very different implementation" I mentioned earlier. No square root is required and the result is a simple power-based mean. – Evan Balster creator of imitone <http://imitone.com> On Thu, Feb

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

2016-02-21 Thread Evan Balster
situational and depends heavily on the context. I've been bitten in the past when designing algorithms around a white noise model and then running my software on systems with integrated noise cancellation. – Evan Balster creator of imitone <http://imitone.com> On Sun, Feb 21, 2016 at 6

Re: [music-dsp] Cheap spectral centroid recipe

2016-02-21 Thread Evan Balster
by first-order implementations, anyway.) – Evan Balster creator of imitone <http://imitone.com> On Fri, Feb 19, 2016 at 7:30 PM, Douglas Repetto <doug...@music.columbia.edu > wrote: > Robert, > > On Fri, Feb 19, 2016 at 3:38 PM, robert bristow-johnson < > r...@

Re: [music-dsp] MIDI Synth Design Advice Please

2016-02-01 Thread Evan Balster
quite a lot, which is why CPU usage rises dramatically as buffer-size falls -- and also why you almost never see buffers smaller than about 16 samples. Evan Balster creator of imitone http://imitone.com On Mon, Feb 1, 2016 at 9:12 AM, Theo Verelst <theo...@theover.org> wrote: > Scott Gr

Re: [music-dsp] confirm a2ab2276c83b0f9c59752d823250447ab4b666

2016-03-28 Thread Evan Balster
This happened to me also, but I didn't give it much thought. On Mon, Mar 28, 2016 at 4:31 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > > > h. i wonder if someone is trying to tell me something > > > > Original Message

Re: [music-dsp] High quality really broad bandwidth pinknoise (ideally more than 32 octaves)

2016-04-12 Thread Evan Balster
As was mentioned earlier, the top-octave scale is 2^16 times the bottom-octave scale (actually 2^(31/2) to be pedantic). Pink noise halves in *power* each octave, not amplitude. I remark because I made the same mistake in reasoning earlier. – Evan Balster creator of imitone <http://imitone.

Re: [music-dsp] High quality really broad bandwidth pinknoise (ideally more than 32 octaves)

2016-04-11 Thread Evan Balster
ling rates between N (inclusive) and 2N (exclusive). With this approach you could get an arbitrarily flat slope -- if you're willing to pay the cost! Your project sounds totally bonkers, but I'll give you the benefit of the doubt on that. :) – Evan Balster creator of imitone <http://imitone.com>

Re: [music-dsp] High quality really broad bandwidth pinknoise (ideally more than 32 octaves)

2016-04-11 Thread Evan Balster
en amplify and mix them according to the -3dB trend. – Evan Balster creator of imitone <http://imitone.com> On Mon, Apr 11, 2016 at 11:57 AM, Seth Nickell <snick...@gmail.com> wrote: > I'm applying an iterative function to an input signal, in this instance > pinknoise. Becaus

Re: [music-dsp] Delays: sampling rate modulation vs. buffer size modulation

2016-03-23 Thread Evan Balster
to the derivative of the delay plus the producer samplerate. – Evan Balster creator of imitone <http://imitone.com> On Wed, Mar 23, 2016 at 4:04 AM, Vadim Zavalishin < vadim.zavalis...@native-instruments.de> wrote: > On 23-Mar-16 00:45, Matthias Puech wrote: > >> Does this mea

Re: [music-dsp] R: Anyone using unums?

2016-04-15 Thread Evan Balster
practical* it would certainly yield some interesting benefits. Even if it can't, perhaps it can inspire something better. * In the case of the complete set and the zero set, the two halves of the range equal; in this case we would want to use an odd or even MSB, or some other pattern, to distin

Re: [music-dsp] Anyone using unums?

2016-04-15 Thread Evan Balster
t bits when sending them over serial connections. It goes without saying that such would require new bus protocols / memory controllers / etc... – Evan Balster creator of imitone <http://imitone.com> On Thu, Apr 14, 2016 at 7:57 PM, Nigel Redmon <earle...@earlevel.com> wrote: > Int

[music-dsp] Supervised DSP architectures (vs. push/pull)

2016-07-27 Thread Evan Balster
lti-core processing mechanisms. I would be very interested to hear from others who have used this type of architecture: Strengths, weaknesses, gotchas, et cetera. – Evan Balster creator of imitone <http://imitone.com> ___ dupswapdr

Re: [music-dsp] Are kalman filters used often in music or audio DSP?

2016-07-24 Thread Evan Balster
regard to the mean-value of its input and output. But in the general case it is much more dynamic. For practical purposes, we use Kalman filters when we want to get a "best guess" at the mean value of a variable based on noisy data. We use linear filters when we want to adjust the frequency conte

Re: [music-dsp] Supervised DSP architectures (vs. push/pull)

2016-07-28 Thread Evan Balster
abstractions** to synchronize state in my audio framework, but for things like worker threads I want to get a grip on the practicalities of using things like condition variables in a low-latency DSP system. – Evan Balster creator of imitone <http://imitone.com> * I expect a "simp

Re: [music-dsp] Supervised DSP architectures (vs. push/pull)

2016-08-01 Thread Evan Balster
memory such as samples, delay lines, et cetera. As I'm learning recently, cache coherency gains from memory re-use are typically most relevant within small pieces of code. If anyone has evidence to the contrary, though, I'd love to see it. – Evan Balster creator of imitone <http://imitone.

Re: [music-dsp] efficient running max algorithm

2016-07-20 Thread Evan Balster
be very interested to hear your thought process with the partial linear search. – Evan Balster creator of imitone <http://imitone.com> On Wed, Jul 20, 2016 at 1:23 PM, Dan Gillespie <dgilles...@cosineaudio.com> wrote: > Regarding the Lemire paper his code is provided here: >

Re: [music-dsp] efficient running max algorithm

2016-07-21 Thread Evan Balster
). But this is a very marginal improvement and it's difficult to write out the bound in a clearer way. – Evan Balster creator of imitone <http://imitone.com> On Thu, Jul 21, 2016 at 7:40 AM, Ethan Fenn <et...@polyspectral.com> wrote: > Yeah, with a binary search, you're doing O(log(w)) work

Re: [music-dsp] idealized flat impact like sound

2016-08-01 Thread Evan Balster
The most essentially flat signal is a delta function or impulse, which is also phase-aligned. Apply any all-pass filter or series thereof to the impulse, and the fourier transform over infinite time will remain flat. I recommend investigating Schroeder filters. – Evan Balster creator of imitone

Re: [music-dsp] ± 45° Hilbert transformer using pair of IIR APFs

2017-02-06 Thread Evan Balster
what sort of filter a similar pattern on the imaginary line produces! (I should improve my own filter testbed...) – Evan Balster creator of imitone <http://imitone.com> On Mon, Feb 6, 2017 at 8:57 PM, Sampo Syreeni <de...@iki.fi> wrote: > On 2017-02-06, Eric Brombaugh wrote: > &g

Re: [music-dsp] Recognizing Frequency Components

2017-01-26 Thread Evan Balster
to other problems where zero-crossings are less useful. – Evan Balster creator of imitone <http://imitone.com> On Thu, Jan 26, 2017 at 9:20 AM, STEFFAN DIEDRICHSEN <sdiedrich...@me.com> wrote: > At that length, you can count zero-crossings. But that’s not a valid > answer, I

Re: [music-dsp] ± 45° Hilbert transformer for pitch detection?

2017-02-09 Thread Evan Balster
a sine wave at 1/3 or 1/4 the detected pitch by the input signal, and then mixing some of the dry signal back in... – Evan Balster creator of imitone <http://imitone.com> On Thu, Feb 9, 2017 at 8:47 AM, gm <g...@voxangelica.net> wrote: > Here is another test with more difficult inp

Re: [music-dsp] efficient running max algorithm

2016-09-02 Thread Evan Balster
. [image: Inline image 3] http://interactopia.com/archive/images/lemire_algorithm.png The algorithm can safely forget anything in grey because it has been "shadowed" by newer maximum or minimum values. – Evan Balster creator of imitone <http://imitone.com> On Fri, Sep 2, 2016

Re: [music-dsp] efficient running max algorithm

2016-09-02 Thread Evan Balster
between them (because the latest sample always appears in both). – Evan Balster creator of imitone <http://imitone.com> On Fri, Sep 2, 2016 at 12:36 PM, Ethan Duni <ethan.d...@gmail.com> wrote: > Right aren't monotonic signals the worst case here? Or maybe not, since > they're w

Re: [music-dsp] efficient running max algorithm

2016-09-03 Thread Evan Balster
em to!) Re: Using STL for DSP, I largely agree (though I'll often do it when I can effectively control allocations). The GitHub code is suitable for high-level use and as a reference implementation. – Evan Balster creator of imitone <http://imitone.com> On Sat, Sep 3, 2016 at 12:42

Re: [music-dsp] efficient running max algorithm

2016-09-03 Thread Evan Balster
, R equals N. Regardless, the average computation per sample is bounded by O(1) even in the worst case. The worst-case for an individual sample is O(log2(R)). – Evan Balster creator of imitone <http://imitone.com> On Sat, Sep 3, 2016 at 11:49 AM, robert bristow-johnson < r...@audioima

Re: [music-dsp] efficient running max algorithm

2016-09-03 Thread Evan Balster
t of my ability; if you doubt it, instrument the code to count comparator calls and see for yourself. – Evan Balster creator of imitone <http://imitone.com> On Sat, Sep 3, 2016 at 1:45 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > > > okay, so it appears, al

Re: [music-dsp] efficient running max algorithm

2016-09-01 Thread Evan Balster
y feedback or thoughts about this. – Evan Balster creator of imitone <http://imitone.com> On Thu, Jul 21, 2016 at 10:16 AM, Evan Balster <e...@imitone.com> wrote: > Ahh, smart! Thanks for the insight; I understand now. > > It occurs to me that you could slightly tighten

Re: [music-dsp] efficient running max algorithm

2016-09-01 Thread Evan Balster
and implemented in my code. High frequencies won't really make a difference. In any case the combined sizes of the two wedges will never exceed R+1, and will typically be much smaller. Feel free to customize the unit test in the GitHub to your satisfaction if you're doubtful. – Evan Balster creator

Re: [music-dsp] Bandlimited morphable waveform generation

2016-09-15 Thread Evan Balster
ilter, or sample from "soft" square and sawtooth functions with a smoothing parameter built in. Given any f(x): Is it possible to sample f(x) with a given sample-rate > ignoring all frequencies (slopes) higher than SF/2? *This question is a pathway into madness.* – Evan Bal

Re: [music-dsp] Help with "Sound Retainer"/Sostenuto Effect

2016-09-16 Thread Evan Balster
e harmonics of the guitar might align with the nulls. – Evan Balster creator of imitone <http://imitone.com> On Fri, Sep 16, 2016 at 3:58 PM, gm <g...@voxangelica.net> wrote: > I never tried the Freeverb algorithm. > Just form inspecting the flow chart I suspect its rather colored w

Re: [music-dsp] Help with "Sound Retainer"/Sostenuto Effect

2016-09-16 Thread Evan Balster
egular intervals. If you're taking the granular approach, I suggest randomizing as much as possible. If you want to avoid interference between the grains, try to synchronize them based on a cross-correlation <https://en.wikipedia.org/wiki/Cross-correlation>. – Evan Balster creator of imitone <ht

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

2016-08-27 Thread Evan Balster
onse <https://en.wikipedia.org/wiki/Window_function#/media/File:Window_function_and_frequency_response_-_Gaussian_(sigma_%3D_0.4).svg> of the clipped Gaussian window results from the discontinuity induced by clipping. – Evan Balster creator of imitone <http://imitone.com> On Sat, Aug

Re: [music-dsp] Floating-point round-off noise and phase increments

2016-08-26 Thread Evan Balster
a performance cost. Kahan summation of 32-bit floats quickly becomes more accurate than naive summation of doubles. – Evan Balster creator of imitone <http://imitone.com> On Fri, Aug 26, 2016 at 9:25 AM, Michael Gogins <michael.gog...@gmail.com> wrote: > Multiply not increment. >

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

2016-08-29 Thread Evan Balster
cted behavior of an "ideal" (infinite) Gaussian window, then with sufficient wrap-around we should be able to get a mostly positive and Gaussian frequency response for each bin without any worries about aliasing. – Evan Balster creator of imitone <http://imitone.com> On Su

Re: [music-dsp] Can anyone figure out this simple, but apparently wrong, mixing technique?

2016-12-20 Thread Evan Balster
how up in surprising places. – Evan Balster creator of imitone <http://imitone.com> On Tue, Dec 20, 2016 at 9:07 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > > > Original Message > Subject: Re: [mu

Re: [music-dsp] Using an actual database for storage of DSP settings

2016-12-28 Thread Evan Balster
This is an interesting idea. I wonder if sqlite would be a good fit for that problem scale? – Evan Balster creator of imitone <http://imitone.com> On Wed, Dec 28, 2016 at 7:52 AM, Sampo Syreeni <de...@iki.fi> wrote: > On 2016-12-28, Theo Verelst wrote: > > Did anyone here

Re: [music-dsp] Allpass filter

2016-12-07 Thread Evan Balster
*the future. If you're willing to tolerate a long, constant delay (increasing in proportion to the accuracy of the magnitude response) you can approximate your lp filter with a symmetric FIR filter design. Sadly you can't cheat the laws of filter theory --- at least, not without venturing outside

Re: [music-dsp] What happened to that FPGA for DSP idea

2017-09-14 Thread Evan Balster
to save even more space? – Evan Balster creator of imitone <http://imitone.com> On Thu, Sep 14, 2017 at 4:02 PM, robert bristow-johnson < r...@audioimagination.com> wrote: > > > well, i know of at least one company that uses an FPGA to replace the ASIC > they used to use. they

Re: [music-dsp] PCM audio amplitudes represent pressure or displacement?

2017-10-02 Thread Evan Balster
, momentum, etc. – Evan Balster creator of imitone <http://imitone.com> On Sun, Oct 1, 2017 at 12:56 PM, Evan Balster <e...@imitone.com> wrote: > DSP programmer recently getting into transducer experimentation here. > Gonna walk through the dimensional analysis: > > >

Re: [music-dsp] PCM audio amplitudes represent pressure or displacement?

2017-10-01 Thread Evan Balster
with its integrals and derivatives. It's simple to transform that velocity signal into a displacement signal or vice versa, but in practice any filtering effects will result in a frequency-dependent mixture of the two (and potentially other degrees of integration). – Evan Balster creator of imitone

Re: [music-dsp] intensity of Doppler effect

2017-10-08 Thread Evan Balster
is still, it receives sound sound energy on its surface over the course of one second. If it's moving left, it received the energy over a smaller window of time, experiencing it as a higher frequency. – Evan Balster creator of imitone <http://imitone.com> On Sun, Oct 8, 2017 at 6:26 PM,

Re: [music-dsp] intensity of Doppler effect

2017-10-11 Thread Evan Balster
quite >> an irrelevant contribution to the intensity of the wave. >> >> *If* all these thoughts are right, >> then the question still remains: >> what (probably negligible) is the contribution >> of the variation of the DC component >> to the intensity (

Re: [music-dsp] Antialias question (Kevin Chi)

2018-06-01 Thread Evan Balster
Here is a wonderful, very skimmable paper that tells you everything you could ever want to know about resampling and provides example code for many techniques: http://yehar.com/blog/wp-content/uploads/2009/08/deip.pdf – Evan Balster creator of imitone <http://imitone.com> On Fri, Jun 1, 2018

Re: [music-dsp] band-limited website

2017-12-23 Thread Evan Balster
I can confirm the error. Maybe if we sample it over a shorter time interval, the bandwidth will increase? – Evan Balster creator of imitone <http://imitone.com> On Sat, Dec 23, 2017 at 6:42 PM, Phil Burk <philb...@mobileer.com> wrote: > I was not looking for the mail list arch

Re: [music-dsp] WSOLA on RealTime

2018-10-04 Thread Evan Balster
h comes out *exactly *the same or you'll get crackles! – Evan Balster creator of imitone <http://imitone.com> On Wed, Oct 3, 2018 at 3:56 PM Alex Dashevski wrote: > Hi, > Could you tell me how to use soundTouch API if I want only to do > resampling ? > I mean: convert from 48

Re: [music-dsp] Sound Analysis

2019-01-01 Thread Evan Balster
ear your zero-crossing, pushing that crossing forward or backward in time. This problem worsens with the level of noise in the signal, especially if the tone is dark. Suppressing the noise requires an estimate of the pitch, creating something of a chicken-and-egg problem — but you can refine an esti

Re: [music-dsp] Time-variant 2nd-order sinusoidal resonator

2019-02-20 Thread Evan Balster
ith a fast inverse square root. For more control over the bandwidth and general responsiveness, it's possible to replace the decay math (which is basically a one-pole filter <https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter>) with another low-pass filter design