aubio: spectral/phasevoc.h Source File

aubio 0.4.6

phasevoc.h
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1 /*
2 Copyright (C) 2003-2013 Paul Brossier <piem@aubio.org>
3
4 This file is part of aubio.
5
6 aubio is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
10
11 aubio is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with aubio. If not, see <http://www.gnu.org/licenses/>.
18
19 */
20
21 /** \file
22
23 Phase vocoder object
24
25 This object implements a phase vocoder. The spectral frames are computed
26 using a HanningZ window and a swapped version of the signal to simplify the
27 phase relationships across frames. The window sizes and overlap are specified
28 at creation time.
29
30 \example spectral/test-phasevoc.c
31
32 */
33
34 #ifndef AUBIO_PHASEVOC_H
35 #define AUBIO_PHASEVOC_H
36
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40
41 /** phasevocoder object */
42 typedef struct _aubio_pvoc_t aubio_pvoc_t;
43
44 /** create phase vocoder object
45
46 \param win_s size of analysis buffer (and length the FFT transform)
47 \param hop_s step size between two consecutive analysis
48
49 */
50 aubio_pvoc_t * new_aubio_pvoc (uint_t win_s, uint_t hop_s);
51 /** delete phase vocoder object
52
53 \param pv phase vocoder object as returned by new_aubio_pvoc
54
55 */
56 void del_aubio_pvoc(aubio_pvoc_t *pv);
57
58 /** compute spectral frame
59
60 This function accepts an input vector of size [hop_s]. The
61 analysis buffer is rotated and filled with the new data. After windowing of
62 this signal window, the Fourier transform is computed and returned in
63 fftgrain as two vectors, magnitude and phase.
64
65 \param pv phase vocoder object as returned by new_aubio_pvoc
66 \param in new input signal (hop_s long)
67 \param fftgrain output spectral frame
68
69 */
70 void aubio_pvoc_do(aubio_pvoc_t *pv, const fvec_t *in, cvec_t * fftgrain);
71 /** compute signal from spectral frame
72
73 This function takes an input spectral frame fftgrain of size
74 [buf_s] and computes its inverse Fourier transform. Overlap-add
75 synthesis is then computed using the previously synthetised frames, and the
76 output stored in out.
77
78 \param pv phase vocoder object as returned by new_aubio_pvoc
79 \param fftgrain input spectral frame
80 \param out output signal (hop_s long)
81
82 */
83 void aubio_pvoc_rdo(aubio_pvoc_t *pv, cvec_t * fftgrain, fvec_t *out);
84
85 /** get window size
86
87 \param pv phase vocoder to get the window size from
88
89 */
90 uint_t aubio_pvoc_get_win(aubio_pvoc_t* pv);
91 /** get hop size
92
93 \param pv phase vocoder to get the hop size from
94
95 */
96 uint_t aubio_pvoc_get_hop(aubio_pvoc_t* pv);
97
98 /** set window type
99
100 \param pv phase vocoder to set the window type
101 \param window_type a string representing a window
102
103 \return 0 if successful, non-zero otherwise
104
105 */
106 uint_t aubio_pvoc_set_window(aubio_pvoc_t *pv, const char_t *window_type);
107
108 #ifdef __cplusplus
109 }
110 #endif
111
112 #endif /* AUBIO_PHASEVOC_H */
aubio_pvoc_do
void aubio_pvoc_do(aubio_pvoc_t *pv, const fvec_t *in, cvec_t *fftgrain)
compute spectral frame
del_aubio_pvoc
void del_aubio_pvoc(aubio_pvoc_t *pv)
delete phase vocoder object
aubio_pvoc_get_hop
uint_t aubio_pvoc_get_hop(aubio_pvoc_t *pv)
get hop size
aubio_pvoc_get_win
uint_t aubio_pvoc_get_win(aubio_pvoc_t *pv)
get window size
new_aubio_pvoc
aubio_pvoc_t * new_aubio_pvoc(uint_t win_s, uint_t hop_s)
create phase vocoder object
aubio_pvoc_set_window
uint_t aubio_pvoc_set_window(aubio_pvoc_t *pv, const char_t *window_type)
set window type
fvec_t
Buffer for real data.
Definition: fvec.h:67
cvec_t
Vector of real-valued phase and spectrum data.
Definition: cvec.h:63
uint_t
unsigned int uint_t
unsigned integer
Definition: types.h:60
aubio_pvoc_t
struct _aubio_pvoc_t aubio_pvoc_t
phasevocoder object
Definition: phasevoc.h:42
char_t
char char_t
character
Definition: types.h:64
aubio_pvoc_rdo
void aubio_pvoc_rdo(aubio_pvoc_t *pv, cvec_t *fftgrain, fvec_t *out)
compute signal from spectral frame