2 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
3 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 #define FFT_FIXED_32 0
35 #include "libavutil/mem.h"
43 typedef float FFTDouble
;
49 #define Q31(x) (int)((x)*2147483648.0 + 0.5)
50 #define FFT_NAME(x) x ## _fixed_32
52 typedef int32_t FFTSample
;
54 #else /* FFT_FIXED_32 */
56 #define FFT_NAME(x) x ## _fixed
58 typedef int16_t FFTSample
;
60 #endif /* FFT_FIXED_32 */
62 typedef struct FFTComplex
{
66 typedef int FFTDouble
;
67 typedef struct FFTContext FFTContext
;
69 #endif /* FFT_FLOAT */
71 typedef struct FFTDComplex
{
77 enum fft_permutation_type
{
79 FF_FFT_PERM_SWAP_LSBS
,
83 enum mdct_permutation_type
{
85 FF_MDCT_PERM_INTERLEAVE
,
93 int mdct_size
; /* size of MDCT (i.e. number of input data * 2) */
94 int mdct_bits
; /* n = 2^nbits */
95 /* pre/post rotation tables */
99 * Do the permutation needed BEFORE calling fft_calc().
101 void (*fft_permute
)(struct FFTContext
*s
, FFTComplex
*z
);
103 * Do a complex FFT with the parameters defined in ff_fft_init(). The
104 * input data must be permuted before. No 1.0/sqrt(n) normalization is done.
106 void (*fft_calc
)(struct FFTContext
*s
, FFTComplex
*z
);
107 void (*imdct_calc
)(struct FFTContext
*s
, FFTSample
*output
, const FFTSample
*input
);
108 void (*imdct_half
)(struct FFTContext
*s
, FFTSample
*output
, const FFTSample
*input
);
109 void (*mdct_calc
)(struct FFTContext
*s
, FFTSample
*output
, const FFTSample
*input
);
110 void (*mdct_calcw
)(struct FFTContext
*s
, FFTDouble
*output
, const FFTSample
*input
);
111 enum fft_permutation_type fft_permutation
;
112 enum mdct_permutation_type mdct_permutation
;
115 #if CONFIG_HARDCODED_TABLES
116 #define COSTABLE_CONST const
118 #define COSTABLE_CONST
121 #define COSTABLE(size) \
122 COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2]
127 extern COSTABLE(128);
128 extern COSTABLE(256);
129 extern COSTABLE(512);
130 extern COSTABLE(1024);
131 extern COSTABLE(2048);
132 extern COSTABLE(4096);
133 extern COSTABLE(8192);
134 extern COSTABLE(16384);
135 extern COSTABLE(32768);
136 extern COSTABLE(65536);
137 extern COSTABLE_CONST FFTSample
* const FFT_NAME(ff_cos_tabs
)[17];
139 #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs)
142 * Initialize the cosine table in ff_cos_tabs[index]
143 * @param index index in ff_cos_tabs array of the table to initialize
145 void ff_init_ff_cos_tabs(int index
);
147 #define ff_fft_init FFT_NAME(ff_fft_init)
148 #define ff_fft_end FFT_NAME(ff_fft_end)
151 * Set up a complex FFT.
152 * @param nbits log2 of the length of the input array
153 * @param inverse if 0 perform the forward transform, if 1 perform the inverse
155 int ff_fft_init(FFTContext
*s
, int nbits
, int inverse
);
157 void ff_fft_init_aarch64(FFTContext
*s
);
158 void ff_fft_init_x86(FFTContext
*s
);
159 void ff_fft_init_arm(FFTContext
*s
);
160 void ff_fft_init_mips(FFTContext
*s
);
161 void ff_fft_init_ppc(FFTContext
*s
);
163 void ff_fft_fixed_init_arm(FFTContext
*s
);
165 void ff_fft_end(FFTContext
*s
);
167 #define ff_mdct_init FFT_NAME(ff_mdct_init)
168 #define ff_mdct_end FFT_NAME(ff_mdct_end)
170 int ff_mdct_init(FFTContext
*s
, int nbits
, int inverse
, double scale
);
171 void ff_mdct_end(FFTContext
*s
);
173 #endif /* AVCODEC_FFT_H */