i have some old MATLAB code that does the phase vocoder implementing 
time-scaling with a little extra thing that scales the sweep rate of sinusoids 
inside the frame.� it is a consequence of this very old paper i did for the 
IEEE WASPAA (Mohonk) in
2001:�https://www.researchgate.net/publication/3927319_Intraframe_time-scaling_of_nonstationary_sinusoids_within_the_phase_vocoder�
drop me a note and i will send you this MATLAB code.� i think it is 
self-contained except for the FFT and polyfit() for fitting a straight line to
some data.
translating that to C or C++ or C# or whatever is the flavor of the month is 
another whole can o' worms.


---------------------------- Original Message ----------------------------

Subject: Re: [music-dsp] phase vocoder

From: "Matt Ingalls" <m...@8dio.com>

Date: Mon, October 15, 2018 2:11 pm

To: music-dsp@music.columbia.edu

--------------------------------------------------------------------------



> well there&rsquo;s this old blog from Stephan Bernsee using a &ldquo;similar 
> process&rdquo; to the phase vocoder

> for frequency domain pitch shifting:

> http://blogs.zynaptiq.com/bernsee/pitch-shifting-using-the-ft/

> http://blogs.zynaptiq.com/bernsee/repo/smbPitchShift.cpp

>

> not sure what your goal is, but at least in my implementation, i wasn&rsquo;t 
> able to get it to sound

> as good (fewer processing artifacts) as time domain solutions..

>

> -m

>

>

>> On Oct 15, 2018, at 9:31 AM, Alex Dashevski <alexd...@gmail.com> wrote:

>>

>> I need the code for pitch shifting on RealTime. Could you help ?

>>

>> ‫בתאריך יום ב׳, 15 באוק׳ 2018 ב-15:15 מאת ‪Eder Souza‬&rlm; 
>> <‪ederwan...@gmail.com <mailto:ederwan...@gmail.com>‬&rlm;>:‬

>> Some time ago I posted some code in matlab, this is not real-time, you can 
>> see the basic math of an standard phase vocoder.

>>

>> https://dsp.stackexchange.com/questions/40101/audio-time-stretching-without-pitch-shifting/40367#40367
>>  
>> <https://dsp.stackexchange.com/questions/40101/audio-time-stretching-without-pitch-shifting/40367#40367>

>>

>> This code just change the time, you can pitch shift using a combination of 
>> the code above and resampler...

>>

>> The core code is the same for real-time or off-line, the only thing that you 
>> need to worry about is how deal with input and output buffer (do you need 
>> ensure output buffer continuity, learn about Circular Buffer).

>>

>> PS: Prepare to latency lol

>>

>>

>> Eder de Souza

>> ♪♫ ♫♪

>> ▇ ▅ █ ▅ ▇ ▂ ▃ ▁ ▁ ▅ ▃ ▅ ▅ ▄ ▅ ▇

>> Sent

>From The Moon and Written With My Thumbs !

>>

>>

>> On Sun, Oct 14, 2018 at 2:11 AM Alex Dashevski <alexd...@gmail.com 
>> <mailto:alexd...@gmail.com>> wrote:

>> Hi,

>> Which library?

>> Thanks,

>> Alex

>>

>> On Sat, Oct 13, 2018, 22:42 he can jog <e...@hecanjog.com 
>> <mailto:e...@hecanjog.com>> wrote:

>> The library is easy to work with. Having enough of a working knowledge of 
>> phase vocoders to make use of an existing implementation and implementing 
>> one from scratch are two different levels of complexity.

>>

>> On Sat, Oct 13, 2018 at 2:31 PM Daniel Varela <danielvarela...@gmail.com 
>> <mailto:danielvarela...@gmail.com>> wrote:

>> Complex stuff have no easy fix

>>

>> El s�b., 13 oct. 2018 20:43, he can jog <e...@hecanjog.com 
>> <mailto:e...@hecanjog.com>> escribi�:

>> Paul Batchelor has a great port of the csound 'mincer' phase vocoder in his 
>> SoundPipe library: 
>> https://github.com/PaulBatchelor/Soundpipe/blob/master/modules/mincer.c 
>> <https://github.com/PaulBatchelor/Soundpipe/blob/master/modules/mincer.c>

>>

>> That's definitely beyond my understanding to re-implement, but his library 
>> is designed to be embedded and has a really nice API, I've found it easy to 
>> work with in my own projects.

>>

>> On Sat, Oct 13, 2018 at 1:31 PM Alex Dashevski <alexd...@gmail.com 
>> <mailto:alexd...@gmail.com>> wrote:

>> Hi,

>>

>> Where can I find a simple explanation and code example(supported RealTime 
>> and multi threading) ?

>> I found https://breakfastquay.com/rubberband/index.html 
>> <https://breakfastquay.com/rubberband/index.html> but it very difficult 
>> undersand how it work, I need to integrate this code into android that 
>> should run on an audio buffer.

>>

>> Thanks,

>> Alex


--



r b-j� � � � � � � � � � � � �r...@audioimagination.com



"Imagination is more important than knowledge."

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