FFmpeg
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 FFmpeg.
6  *
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.
11  *
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.
16  *
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
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 #ifndef FFT_FIXED_32
30 #define FFT_FIXED_32 0
31 #endif
32 
33 #include <stdint.h>
34 #include "config.h"
35 #include "libavutil/mem.h"
36 
37 #if FFT_FLOAT
38 
39 #include "avfft.h"
40 
41 #define FFT_NAME(x) x
42 
43 typedef float FFTDouble;
44 
45 #else
46 
47 #if FFT_FIXED_32
48 
49 #define Q31(x) (int)((x)*2147483648.0 + 0.5)
50 #define FFT_NAME(x) x ## _fixed_32
51 
52 typedef int32_t FFTSample;
53 
54 #else /* FFT_FIXED_32 */
55 
56 #define FFT_NAME(x) x ## _fixed
57 
58 typedef int16_t FFTSample;
59 
60 #endif /* FFT_FIXED_32 */
61 
62 typedef struct FFTComplex {
63  FFTSample re, im;
64 } FFTComplex;
65 
66 typedef int FFTDouble;
67 typedef struct FFTContext FFTContext;
68 
69 #endif /* FFT_FLOAT */
70 
71 typedef struct FFTDComplex {
73 } FFTDComplex;
74 
75 /* FFT computation */
76 
81 };
82 
86 };
87 
88 struct FFTContext {
89  int nbits;
90  int inverse;
91  uint16_t *revtab;
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 */
98  /**
99  * Do the permutation needed BEFORE calling fft_calc().
100  */
101  void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
102  /**
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.
105  */
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);
113  uint32_t *revtab32;
114 };
115 
116 #if CONFIG_HARDCODED_TABLES
117 #define COSTABLE_CONST const
118 #else
119 #define COSTABLE_CONST
120 #endif
121 
122 #define COSTABLE(size) \
123  COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2]
124 
125 extern COSTABLE(16);
126 extern COSTABLE(32);
127 extern COSTABLE(64);
128 extern COSTABLE(128);
129 extern COSTABLE(256);
130 extern COSTABLE(512);
131 extern COSTABLE(1024);
132 extern COSTABLE(2048);
133 extern COSTABLE(4096);
134 extern COSTABLE(8192);
135 extern COSTABLE(16384);
136 extern COSTABLE(32768);
137 extern COSTABLE(65536);
138 extern COSTABLE(131072);
139 extern COSTABLE_CONST FFTSample* const FFT_NAME(ff_cos_tabs)[18];
140 
141 #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs)
142 
143 /**
144  * Initialize the cosine table in ff_cos_tabs[index]
145  * @param index index in ff_cos_tabs array of the table to initialize
146  */
147 void ff_init_ff_cos_tabs(int index);
148 
149 #define ff_fft_init FFT_NAME(ff_fft_init)
150 #define ff_fft_end FFT_NAME(ff_fft_end)
151 
152 /**
153  * Set up a complex FFT.
154  * @param nbits log2 of the length of the input array
155  * @param inverse if 0 perform the forward transform, if 1 perform the inverse
156  */
157 int ff_fft_init(FFTContext *s, int nbits, int inverse);
158 
159 void ff_fft_init_aarch64(FFTContext *s);
160 void ff_fft_init_x86(FFTContext *s);
161 void ff_fft_init_arm(FFTContext *s);
162 void ff_fft_init_mips(FFTContext *s);
163 void ff_fft_init_ppc(FFTContext *s);
164 
165 void ff_fft_fixed_init_arm(FFTContext *s);
166 
167 void ff_fft_end(FFTContext *s);
168 
169 #define ff_mdct_init FFT_NAME(ff_mdct_init)
170 #define ff_mdct_end FFT_NAME(ff_mdct_end)
171 
172 int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
173 void ff_mdct_end(FFTContext *s);
174 
175 #endif /* AVCODEC_FFT_H */
float FFTDouble
Definition: fft.h:43
mdct_permutation_type
Definition: fft.h:83
Memory handling functions.
void ff_fft_init_arm(FFTContext *s)
Definition: fft_init_arm.c:38
FFTSample re
Definition: avfft.h:38
void FFTComplex
Definition: tx_priv.h:38
#define COSTABLE(size)
Definition: fft.h:122
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce output
static void fft_permute(FFTContext *s, FFTComplex *z)
Definition: fft.c:259
void ff_fft_init_ppc(FFTContext *s)
Definition: fft_init.c:151
FFTDouble re
Definition: fft.h:72
#define FFT_NAME(x)
Definition: fft.h:41
void(* mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input)
Definition: fft.h:110
#define ff_mdct_init
Definition: fft.h:169
float FFTSample
Definition: avfft.h:35
void ff_fft_fixed_init_arm(FFTContext *s)
Definition: fft.h:88
FFTSample * tsin
Definition: fft.h:97
uint32_t * revtab32
Definition: fft.h:113
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
int nbits
Definition: fft.h:89
#define ff_fft_init
Definition: fft.h:149
int inverse
Definition: fft.h:90
int32_t
#define s(width, name)
Definition: cbs_vp9.c:257
enum fft_permutation_type fft_permutation
Definition: fft.h:111
static void mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.c:241
FFT functions.
int index
Definition: gxfenc.c:89
static void fft_calc(FFTContext *s, FFTComplex *z)
Definition: fft.c:268
int mdct_bits
Definition: fft.h:94
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some input
fft_permutation_type
Definition: fft.h:77
void(* imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:108
#define ff_init_ff_cos_tabs
Definition: fft.h:141
void ff_fft_init_aarch64(FFTContext *s)
FFTSample im
Definition: avfft.h:38
#define ff_mdct_end
Definition: fft.h:170
#define COSTABLE_CONST
Definition: fft.h:119
static void imdct_calc(DBEContext *s, DBEGroup *g, float *result, float *values)
Definition: dolby_e.c:497
#define ff_fft_end
Definition: fft.h:150
FFTSample * tcos
Definition: fft.h:96
void ff_fft_init_mips(FFTContext *s)
FFT transform.
Definition: fft_mips.c:501
uint16_t * revtab
Definition: fft.h:91
static uint32_t inverse(uint32_t v)
find multiplicative inverse modulo 2 ^ 32
Definition: asfcrypt.c:35
int mdct_size
Definition: fft.h:93
enum mdct_permutation_type mdct_permutation
Definition: fft.h:112
void ff_fft_init_x86(FFTContext *s)
Definition: fft_init.c:27
FFTComplex * tmp_buf
Definition: fft.h:92