andrew@0: /*
andrew@0:    Copyright (C) 2003 Paul Brossier
andrew@0: 
andrew@0:    This program is free software; you can redistribute it and/or modify
andrew@0:    it under the terms of the GNU General Public License as published by
andrew@0:    the Free Software Foundation; either version 2 of the License, or
andrew@0:    (at your option) any later version.
andrew@0: 
andrew@0:    This program is distributed in the hope that it will be useful,
andrew@0:    but WITHOUT ANY WARRANTY; without even the implied warranty of
andrew@0:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
andrew@0:    GNU General Public License for more details.
andrew@0: 
andrew@0:    You should have received a copy of the GNU General Public License
andrew@0:    along with this program; if not, write to the Free Software
andrew@0:    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
andrew@0: 
andrew@0: */
andrew@0: 
andrew@0: /** \file
andrew@0: 
andrew@0:   Phase vocoder object
andrew@0: 
andrew@0:   This object implements a phase vocoder. The spectral frames are computed
andrew@0:   using a HanningZ window and a swapped version of the signal to simplify the
andrew@0:   phase relationships across frames. The window sizes and overlap are specified
andrew@0:   at creation time. Multiple channels are fully supported.
andrew@0: 
andrew@0: */
andrew@0: 
andrew@0: #ifndef _PHASEVOC_H
andrew@0: #define _PHASEVOC_H
andrew@0: 
andrew@0: #ifdef __cplusplus
andrew@0: extern "C" {
andrew@0: #endif
andrew@0: 
andrew@0: /** phasevocoder object */
andrew@0: typedef struct _aubio_pvoc_t aubio_pvoc_t;
andrew@0: 
andrew@0: /** create phase vocoder object
andrew@0: 
andrew@0:   \param win_s size of analysis buffer (and length the FFT transform)
andrew@0:   \param hop_s step size between two consecutive analysis
andrew@0:   \param channels number of channels
andrew@0: 
andrew@0: */
andrew@0: aubio_pvoc_t * new_aubio_pvoc (ba_uint_t win_s, ba_uint_t hop_s, ba_uint_t channels);
andrew@0: /** delete phase vocoder object
andrew@0: 
andrew@0:   \param pv phase vocoder object as returned by new_aubio_pvoc
andrew@0: 
andrew@0: */
andrew@0: void del_aubio_pvoc(aubio_pvoc_t *pv);
andrew@0: 
andrew@0: /** compute spectral frame
andrew@0:   
andrew@0:   This function accepts an input vector of size [channels]x[hop_s]. The
andrew@0:   analysis buffer is rotated and filled with the new data. After windowing of
andrew@0:   this signal window, the Fourier transform is computed and returned in
andrew@0:   fftgrain as two vectors, magnitude and phase.
andrew@0: 
andrew@0:   \param pv phase vocoder object as returned by new_aubio_pvoc
andrew@0:   \param in new input signal (hop_s long) 
andrew@0:   \param fftgrain output spectral frame
andrew@0: 
andrew@0: */
andrew@0: void aubio_pvoc_do(aubio_pvoc_t *pv, fvec_t *in, cvec_t * fftgrain);
andrew@0: /** compute signal from spectral frame
andrew@0: 
andrew@0:   This function takes an input spectral frame fftgrain of size
andrew@0:   [channels]x[buf_s] and computes its inverse Fourier transform. Overlap-add
andrew@0:   synthesis is then computed using the previously synthetised frames, and the
andrew@0:   output stored in out.
andrew@0:   
andrew@0:   \param pv phase vocoder object as returned by new_aubio_pvoc
andrew@0:   \param fftgrain input spectral frame
andrew@0:   \param out output signal (hop_s long) 
andrew@0: 
andrew@0: */
andrew@0: void aubio_pvoc_rdo(aubio_pvoc_t *pv, cvec_t * fftgrain, fvec_t *out);
andrew@0: 
andrew@0: /** get window size
andrew@0: 
andrew@0:   \param pv phase vocoder to get the window size from
andrew@0: 
andrew@0: */
andrew@0: ba_uint_t aubio_pvoc_get_win(aubio_pvoc_t* pv);
andrew@0: /** get hop size
andrew@0: 
andrew@0:   \param pv phase vocoder to get the hop size from
andrew@0: 
andrew@0: */
andrew@0: ba_uint_t aubio_pvoc_get_hop(aubio_pvoc_t* pv);
andrew@0: /** get channel number
andrew@0:  
andrew@0:   \param pv phase vocoder to get the number of channels from
andrew@0: 
andrew@0: */
andrew@0: ba_uint_t aubio_pvoc_get_channels(aubio_pvoc_t* pv);
andrew@0: 
andrew@0: #ifdef __cplusplus
andrew@0: }
andrew@0: #endif 
andrew@0: 
andrew@0: #endif