# New phase-vocoder techniques for pitch-shifting, harmonizing and other exotic effects

@article{Laroche1999NewPT, title={New phase-vocoder techniques for pitch-shifting, harmonizing and other exotic effects}, author={Jean Laroche and Mark Dolson}, journal={Proceedings of the 1999 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics. WASPAA'99 (Cat. No.99TH8452)}, year={1999}, pages={91-94} }

The phase-vocoder is usually presented as a high-quality solution for time-scale modification of signals, pitch-scale modifications usually being implemented as a combination of timescaling and sampling rate conversion. We present two new phase-vocoder-based techniques which allow direct manipulation of the signal in the frequency-domain, enabling such applications as pitch-shifting, chorusing, harmonizing, partial stretching and other exotic modifications which cannot be achieved by the…

## 106 Citations

### Polyphonic Pitch Modification Using Phase Vocoder Techniques

- Physics
- 2010

In the field of digital music processing, the phase vocoder is a well-established tool for pitch shifting and time scaling. Dolson and Laroche (1999) suggest a peak based phase vocoder, which opens…

### A time scale modification with large and varying scaling factors

- Computer Science2016 IEEE International Symposium on Signal Processing and Information Technology (ISSPIT)
- 2016

Interpolated intermediate frames are introduced to compensate for missing signal information and have linear interpolated amplitudes and the desired characteristics could be achieved by a high quality implementation of the new method.

### PITCH SHIFTING OF AUDIO SIGNALS USING THE CONSTANT-Q TRANSFORM

- Engineering
- 2012

Pitch-scale modifications of polyphonic music are usually performed by manipulating the time-frequency representation of the input signal. Most approaches proposed in the past are thereby based on…

### Estimation of Frequency for AM/FM Models Using the Phase Vocoder Framework

- Computer ScienceIEEE Transactions on Signal Processing
- 2008

The robustness of the estimation against noise is studied, both theoretically and experimentally, and the performance is assessed in comparison with two state-of-the-art algorithms: an unmodified version of the reassignment method and a quadratically interpolated fast Fourier transform method.

### Real Time signal Transposition with envelope Preservation in the phase vocoder

- Computer ScienceICMC
- 2005

The implementation that is presented reduces the run time required by the algorithm depending on the cepstral order on the estimation parameters by a factor of 2 to 9 such that real time processing becomes feasible.

### REAL TIME SIGNAL TRANSPOSITION WITH ENVELOPE PRESERVATION IN THE PHASE VOCODER

- Computer Science
- 2005

The implementation that is presented reduces the run time required by the algorithm depending on the cepstral order on the estimation parameters by a factor of 2 to 9 such that real time processing becomes feasible.

### Phase Vocoder For Time Stretch Based On Center Frequency Estimation

- Computer ScienceINTERSPEECH
- 2022

The proposed phase correction algorithm uses peak phase-locking and a method to find an appropriate dominant peak frequency, and it requires only a single sized FFT and has the advantage that it can be easily applied to various applications thanks to its structural similarity to the classical phase vocoder.

### Suppression of phasiness for time-scale modifications of speech signals based on a shape invariance property

- Physics2001 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.01CH37221)
- 2001

An algorithm that preserves the shape invariance of speech signals in the context of a phase vocoder is described that is of high quality and free from transient smearing or phasiness.

### Design of a pitch quantization and pitch correction system for real-time music effects signal processing

- Computer Science, EngineeringProceedings of The 2012 Asia Pacific Signal and Information Processing Association Annual Summit and Conference
- 2012

This paper describes the design of a practical, real-time pitch quantization system intended for digital musical effects signal processing, and employs tools such as an octave resolver and range limiter, grain boundary expansion and contraction, and transient detection to enhance the performance of the system.

### A comparative evaluation of pitch modification techniques

- Engineering2010 18th European Signal Processing Conference
- 2010

Despite its higher compression level, the Deterministic plus Stochastic Model of the residual signal technique is shown to give similar or better results than other methods, especially for male speakers and important ratios of modification.

## References

SHOWING 1-10 OF 15 REFERENCES

### Improved phase vocoder time-scale modification of audio

- PhysicsIEEE Trans. Speech Audio Process.
- 1999

This paper examines the problem of phasiness in the context of time-scale modification and provides new insights into its causes, and two extensions to the standard phase vocoder algorithm are introduced, and the resulting sound quality is shown to be significantly improved.

### Phase-vocoder: about this phasiness business

- PhysicsProceedings of 1997 Workshop on Applications of Signal Processing to Audio and Acoustics
- 1997

The problem of phasiness in the context of time-scale modification of signals, and two new phase synchronization schemes which are shown to both significantly improve the sound quality, and reduce the computational cost of such modifications are examined.

### Phase-locked vocoder

- Computer ScienceProceedings of 1995 Workshop on Applications of Signal Processing to Audio and Accoustics
- 1995

An improved formulation of the phase vocoder is proposed for which the first difficulty does not arise; and a means of phase-locking adjacent channels of the resynthesis is proposed which alleviates the second one.

### Variable-frequency synthesis: An improved harmonic coding scheme

- Computer ScienceICASSP
- 1984

Harmonic Coding is synthesized in the time domain, as a superimposition of "harmonics" whose instantaneous frequency varies continuously along an interpolation curve, within each frame, so that fast pitch variations can be tracked with no difficulty.

### A unified approach to short-time Fourier analysis and synthesis

- Computer ScienceProceedings of the IEEE
- 1977

The effects of modifications made to the short-time transform are explicitly shown on the resulting signal and it is shown that a formal duality exists between the two synthesis methods based on the properties of the window used for obtaining theshort-time Fourier transform.

### Splitting the unit delay [FIR/all pass filters design]

- Computer ScienceIEEE Signal Process. Mag.
- 1996

This work presents a comprehensive review of FIR and allpass filter design techniques for bandlimited approximation of a fractional digital delay, focusing on simple and efficient methods that are well suited for fast coefficient update or continuous control of the delay value.

### Speech analysis/Synthesis based on a sinusoidal representation

- PhysicsIEEE Trans. Acoust. Speech Signal Process.
- 1986

A sinusoidal model for the speech waveform is used to develop a new analysis/synthesis technique that is characterized by the amplitudes, frequencies, and phases of the component sine waves, which forms the basis for new approaches to the problems of speech transformations including time-scale and pitch-scale modification, and midrate speech coding.

### A sound analysis/synthesis system based on a deterministic plus stochastic decomposition

- Physics
- 1990

This paper addresses the second category of synthesis technique: spectrum modeling and describes a technique called specftal modeling synthesis {SMSl, that models time-varying spectra as a collection of sinusoids controlled through time by piecewise linear amplitude and frequency envelopes.

### Phase vocoder

- Physics
- 1966

A vocoder technique is described in which speech signals are represented by their short-time phase and amplitude spectra, which leads to an economy in transmission bandwidth and to a means for time compression and expansion of speech signals.

### Short-time Fourier analysis of sampled speech

- Engineering, Business
- 1981

The theoretical basis for the representation of a speech signal by its short-time Fourier transform is developed. A time-frequency representation for linear time-varying systems is applied to the…