RTPGHI - Real-Time Phase Gradient Integration

Usage

c=rtpghi(s,gamma,a,M);
[c,newphase,tgrad,fgrad] = rtpghi(...);

Input parameters

`s`	Initial coefficients.
`gamma`	Window width factor.
`a`	Hop factor.
`M`	Number of channels.

Output parameters

`c`	Coefficients with the constructed phase.
`newphase`	Just the (unwrapped) phase.
`tgrad`	Relative time phase derivative.
`fgrad`	Relative frequency phase derivative.

Description

rtpghi(s,gamma,a,M) creates complex DGTREAL coefficients from their absolute values s using the Real-Time Phase Gradient Heap Integration algorithm. s must have been obtained as:

c = dgtreal(f,g,a,M,'timeinv');
s = abs(c);

and the algorithm attempts to recover c. Parameter gamma is window g specific and it can be computed using pghi_findgamma.

This function works entirely simiral to pghi except it is using the real-time version of the algorithm. Please see help of pghi (resp. constructphasereal from LTFAT) for more details.

Algorithm version:

'normal' 1 frame delay version of the algorithm RTPGHI(1)

'causal' No delay version of the algorithm RTPGHI(0)

References:

Z. Průša, P. Balazs, and P. L. Søndergaard. A Noniterative Method for Reconstruction of Phase from STFT Magnitude. IEEE/ACM Trans. on Audio, Speech, and Lang. Process., 25(5), May 2017. [ DOI ]

Z. Průša and P. L. Søndergaard. Real-Time Spectrogram Inversion Using Phase Gradient Heap Integration. In Proc. Int. Conf. Digital Audio Effects (DAFx-16), Sep 2016.