1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
/*
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_FFT_H
#define AVCODEC_FFT_H
#ifndef FFT_FLOAT
#define FFT_FLOAT 1
#endif
#ifndef FFT_FIXED_32
#define FFT_FIXED_32 0
#endif
#include <stdint.h>
#include "config.h"
#include "libavutil/mem.h"
#if FFT_FLOAT
#include "avfft.h"
#define FFT_NAME(x) x
typedef float FFTDouble;
#else
#if FFT_FIXED_32
#define Q31(x) (int)((x)*2147483648.0 + 0.5)
#define FFT_NAME(x) x ## _fixed_32
typedef int32_t FFTSample;
#else /* FFT_FIXED_32 */
#define FFT_NAME(x) x ## _fixed
typedef int16_t FFTSample;
#endif /* FFT_FIXED_32 */
typedef struct FFTComplex {
FFTSample re, im;
} FFTComplex;
typedef int FFTDouble;
typedef struct FFTContext FFTContext;
#endif /* FFT_FLOAT */
typedef struct FFTDComplex {
FFTDouble re, im;
} FFTDComplex;
/* FFT computation */
enum fft_permutation_type {
FF_FFT_PERM_DEFAULT,
FF_FFT_PERM_SWAP_LSBS,
FF_FFT_PERM_AVX,
};
enum mdct_permutation_type {
FF_MDCT_PERM_NONE,
FF_MDCT_PERM_INTERLEAVE,
};
struct FFTContext {
int nbits;
int inverse;
uint16_t *revtab;
FFTComplex *tmp_buf;
int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
int mdct_bits; /* n = 2^nbits */
/* pre/post rotation tables */
FFTSample *tcos;
FFTSample *tsin;
/**
* Do the permutation needed BEFORE calling fft_calc().
*/
void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
/**
* Do a complex FFT with the parameters defined in ff_fft_init(). The
* input data must be permuted before. No 1.0/sqrt(n) normalization is done.
*/
void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
void (*mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input);
enum fft_permutation_type fft_permutation;
enum mdct_permutation_type mdct_permutation;
};
#if CONFIG_HARDCODED_TABLES
#define COSTABLE_CONST const
#else
#define COSTABLE_CONST
#endif
#define COSTABLE(size) \
COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2]
extern COSTABLE(16);
extern COSTABLE(32);
extern COSTABLE(64);
extern COSTABLE(128);
extern COSTABLE(256);
extern COSTABLE(512);
extern COSTABLE(1024);
extern COSTABLE(2048);
extern COSTABLE(4096);
extern COSTABLE(8192);
extern COSTABLE(16384);
extern COSTABLE(32768);
extern COSTABLE(65536);
extern COSTABLE_CONST FFTSample* const FFT_NAME(ff_cos_tabs)[17];
#define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs)
/**
* Initialize the cosine table in ff_cos_tabs[index]
* @param index index in ff_cos_tabs array of the table to initialize
*/
void ff_init_ff_cos_tabs(int index);
#define ff_fft_init FFT_NAME(ff_fft_init)
#define ff_fft_end FFT_NAME(ff_fft_end)
/**
* Set up a complex FFT.
* @param nbits log2 of the length of the input array
* @param inverse if 0 perform the forward transform, if 1 perform the inverse
*/
int ff_fft_init(FFTContext *s, int nbits, int inverse);
void ff_fft_init_aarch64(FFTContext *s);
void ff_fft_init_x86(FFTContext *s);
void ff_fft_init_arm(FFTContext *s);
void ff_fft_init_mips(FFTContext *s);
void ff_fft_init_ppc(FFTContext *s);
void ff_fft_fixed_init_arm(FFTContext *s);
void ff_fft_end(FFTContext *s);
#define ff_mdct_init FFT_NAME(ff_mdct_init)
#define ff_mdct_end FFT_NAME(ff_mdct_end)
int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
void ff_mdct_end(FFTContext *s);
#endif /* AVCODEC_FFT_H */
|
