Libav
fft.h
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1 /*
2  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
3  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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.
11  *
12  * Libav 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.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVCODEC_FFT_H
23 #define AVCODEC_FFT_H
24 
25 #ifndef FFT_FLOAT
26 #define FFT_FLOAT 1
27 #endif
28 
29 #include <stdint.h>
30 #include "config.h"
31 #include "libavutil/mem.h"
32 
33 #if FFT_FLOAT
34 
35 #include "avfft.h"
36 
37 #define FFT_NAME(x) x
38 
39 typedef float FFTDouble;
40 
41 #else
42 
43 #define FFT_NAME(x) x ## _fixed
44 
45 typedef int16_t FFTSample;
46 typedef int FFTDouble;
47 
48 typedef struct FFTComplex {
49  int16_t re, im;
50 } FFTComplex;
51 
52 typedef struct FFTContext FFTContext;
53 
54 #endif /* FFT_FLOAT */
55 
56 typedef struct FFTDComplex {
58 } FFTDComplex;
59 
60 /* FFT computation */
61 
66 };
67 
71 };
72 
73 struct FFTContext {
74  int nbits;
75  int inverse;
76  uint16_t *revtab;
78  int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
79  int mdct_bits; /* n = 2^nbits */
80  /* pre/post rotation tables */
91  void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
92  void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
93  void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
94  void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
95  void (*mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input);
98 };
99 
100 #if CONFIG_HARDCODED_TABLES
101 #define COSTABLE_CONST const
102 #else
103 #define COSTABLE_CONST
104 #endif
105 
106 #define COSTABLE(size) \
107  COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2]
108 
109 extern COSTABLE(16);
110 extern COSTABLE(32);
111 extern COSTABLE(64);
112 extern COSTABLE(128);
113 extern COSTABLE(256);
114 extern COSTABLE(512);
115 extern COSTABLE(1024);
116 extern COSTABLE(2048);
117 extern COSTABLE(4096);
118 extern COSTABLE(8192);
119 extern COSTABLE(16384);
120 extern COSTABLE(32768);
121 extern COSTABLE(65536);
122 extern COSTABLE_CONST FFTSample* const FFT_NAME(ff_cos_tabs)[17];
123 
124 #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs)
125 
130 void ff_init_ff_cos_tabs(int index);
131 
132 #define ff_fft_init FFT_NAME(ff_fft_init)
133 #define ff_fft_end FFT_NAME(ff_fft_end)
134 
140 int ff_fft_init(FFTContext *s, int nbits, int inverse);
141 
143 void ff_fft_init_x86(FFTContext *s);
144 void ff_fft_init_arm(FFTContext *s);
145 void ff_fft_init_ppc(FFTContext *s);
146 
148 
149 void ff_fft_end(FFTContext *s);
150 
151 #define ff_mdct_init FFT_NAME(ff_mdct_init)
152 #define ff_mdct_end FFT_NAME(ff_mdct_end)
153 
154 int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
155 void ff_mdct_end(FFTContext *s);
156 
157 #endif /* AVCODEC_FFT_H */
float FFTDouble
Definition: fft.h:39
mdct_permutation_type
Definition: fft.h:68
void(* mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:94
memory handling functions
void(* fft_permute)(struct FFTContext *s, FFTComplex *z)
Do the permutation needed BEFORE calling fft_calc().
Definition: fft.h:86
void ff_fft_init_arm(FFTContext *s)
Definition: fft_init_arm.c:39
FFTSample re
Definition: avfft.h:38
#define COSTABLE(size)
Definition: fft.h:106
void ff_fft_init_ppc(FFTContext *s)
Definition: fft_init.c:144
FFTDouble re
Definition: fft.h:57
#define FFT_NAME(x)
Definition: fft.h:37
#define ff_mdct_init
Definition: fft.h:151
float FFTSample
Definition: avfft.h:35
void(* imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:92
void ff_fft_fixed_init_arm(FFTContext *s)
Definition: fft.h:73
FFTSample * tsin
Definition: fft.h:82
int nbits
Definition: fft.h:74
#define ff_fft_init
Definition: fft.h:132
int inverse
Definition: fft.h:75
enum fft_permutation_type fft_permutation
Definition: fft.h:96
FFT functions.
static void(WINAPI *cond_broadcast)(pthread_cond_t *cond)
void(* imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:93
int index
Definition: gxfenc.c:72
int mdct_bits
Definition: fft.h:79
fft_permutation_type
Definition: fft.h:62
#define ff_init_ff_cos_tabs
Definition: fft.h:124
void ff_fft_init_aarch64(FFTContext *s)
FFTSample im
Definition: avfft.h:38
#define ff_mdct_end
Definition: fft.h:152
#define COSTABLE_CONST
Definition: fft.h:103
#define ff_fft_end
Definition: fft.h:133
FFTSample * tcos
Definition: fft.h:81
void(* fft_calc)(struct FFTContext *s, FFTComplex *z)
Do a complex FFT with the parameters defined in ff_fft_init().
Definition: fft.h:91
FFTDouble im
Definition: fft.h:57
uint16_t * revtab
Definition: fft.h:76
static uint32_t inverse(uint32_t v)
find multiplicative inverse modulo 2 ^ 32
Definition: asfcrypt.c:35
int mdct_size
Definition: fft.h:78
enum mdct_permutation_type mdct_permutation
Definition: fft.h:97
void(* mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input)
Definition: fft.h:95
void ff_fft_init_x86(FFTContext *s)
Definition: fft_init.c:25
FFTComplex * tmp_buf
Definition: fft.h:77