1 /*****************************************************************************
2 * fft.h: Headers for iterative implementation of a FFT
3 *****************************************************************************
4 * $Id: fft.h,v 1.2 2003/10/24 17:43:51 sam Exp $
6 * Mainly taken from XMMS's code
8 * Authors: Richard Boulton <richard@tartarus.org>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
28 #define FFT_BUFFER_SIZE_LOG 9
30 #define FFT_BUFFER_SIZE (1 << FFT_BUFFER_SIZE_LOG)
32 /* sound sample - should be an signed 16 bit value */
33 typedef short int sound_sample;
35 struct _struct_fft_state {
36 /* Temporary data stores to perform FFT in. */
37 float real[FFT_BUFFER_SIZE];
38 float imag[FFT_BUFFER_SIZE];
42 typedef struct _struct_fft_state fft_state;
43 fft_state *visual_fft_init (void);
44 void fft_perform (const sound_sample *input, float *output, fft_state *state);
45 void fft_close (fft_state *state);