1 /* Libvisual - The audio visualisation framework. 2 * 3 * Copyright (C) 2004, 2005 Dennis Smit <ds@nerds-incorporated.org> 4 * 5 * Iterative FFT implementation found in this file is 6 * Copyright (C) 1999 Richard Boulton <richard@tartarus.org> 7 * Richard gave permission to relicense the FFT code under the LGPL. 8 * 9 * Authors: Richard Boulton <richard@tartarus.org> 10 * Dennis Smit <ds@nerds-incorporated.org> 11 * 12 * $Id: 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU Lesser General Public License as 16 * published by the Free Software Foundation; either version 2.1 17 * of the License, or (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU Lesser General Public License for more details. 23 * 24 * You should have received a copy of the GNU Lesser General Public License 25 * along with this program; if not, write to the Free Software 26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 27 */ 28 29 #ifndef _LV_FFT_H 30 #define _LV_FFT_H 31 32 #include <libvisual/lv_common.h> 33 34 #ifdef __cplusplus 35 extern "C" { 36 #endif /* __cplusplus */ 37 38 #define VISUAL_FFTSTATE(obj) (VISUAL_CHECK_CAST ((obj), 0, VisFFTState)) 39 40 /** 41 * Private FFT define that contains the log size. 42 */ 43 #define VISUAL_FFT_BUFFER_SIZE_LOG 9 44 45 /** 46 * Private FFT define that contains the buffer size. 47 */ 48 #define VISUAL_FFT_BUFFER_SIZE (1 << VISUAL_FFT_BUFFER_SIZE_LOG) 49 50 typedef struct _VisFFTState VisFFTState; 51 52 /** 53 * Private structure to contain Fast Fourier Transform states in. 54 */ 55 struct _VisFFTState { 56 VisObject object; /**< The VisObject data. */ 57 /* Temporary data stores to perform FFT in. */ 58 float real[VISUAL_FFT_BUFFER_SIZE]; /**< Private data that is used by the FFT engine. */ 59 float imag[VISUAL_FFT_BUFFER_SIZE]; /**< Private data that is used by the FFT engine. */ 60 }; 61 62 VisFFTState *visual_fft_init (void); 63 void visual_fft_perform (int16_t *input, float *output, VisFFTState *state); 64 65 #ifdef __cplusplus 66 } 67 #endif /* __cplusplus */ 68 69 #endif /* _LV_FFT_H */ 70