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Instructions for using the auto-tune program yourself.

Installation instructions

This .zip archive contains the main function, autotune.m, as well as the helper routines pitchShift.m, fusionFrames.m, and createFrames.m. To install the program, first you must extract it from the archive. In Windows, this can be done by right-clicking on the .zip and selecting “extract here.” Similar methods exist for other operating systems. Next, copy all of the files to your MATLAB directory, or any other directory in your MATLAB path. If you copy the files as part of a folder, then the folder must be included in your MATLAB path for MATLAB to find the autotune function.

The pitch shifting code is a slight modification of the “Guitar Pitch Shifter” from this site . Note that while it is open-source, there may be legal issues with redistributing this code. Do so at your own risk. These issues can be avoided by substituting the pitch shifter for your own pitch shifting code, replacing the call to pitchShift() in autotune.m.

Using the program

The autotune function takes in five arguments, X, pMin, pMax, w, and Fs.

X is the input signal, which is a matrix of amplitudes in either mono (one column) or stereo (two columns). This matrix can be extracted from a .wav file with the wavread command in MATLAB.

pMin is the minimum frequency in which we expect to find a peak, and pMax is the maximum, in Hz. We suggest passing in 60 for pMin and 1050 for pMax to cover the human vocal range, but this interval may need to be expanded for other instruments. In general, the narrowest possible interval covering all played notes is preferable, as this grants the greatest chance of correctly detecting the correct note.

w is the width of the window to correct as if it were an individual note. Note that the current version of the code rounds w to the next power of two, for simplicity. Theoretically, higher values of w would result in less distortion, but also poorer time resolution, where the boundaries between notes would be less precise. We found that 256 was a good value for this parameter.

Finally, Fs is the sampling frequency, in Hz, of the input signal X. This value can be obtained as the second return value of the wavread command, and is commonly either 22050 or 44100. Here is an example of the proper MATLAB commands to auto-tune a vocal sample:

[X, Fs] = wavread('path to input file'); % Read input from .wavout = autotune(X, 60, 1050, Fs); % Process signal wavwrite(out, Fs, 'path to output file'); % Write output to .wav

Alternatively, the output can be played from the MATLAB command line with the following command:

soundsc(out, Fs);

Note that the current version of the code compresses stereo input to mono output, and that execution time can be greatly reduced by processing only a portion of the input song. Please enjoy our code, and feel free to modify and improve upon it!

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Auto-tune. OpenStax CNX. Dec 20, 2012 Download for free at http://cnx.org/content/col11474/1.1
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