Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / fft.h
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 {
72 FFTDouble re, im;
73 } FFTDComplex;
74
75 /* FFT computation */
76
77 enum fft_permutation_type {
78 FF_FFT_PERM_DEFAULT,
79 FF_FFT_PERM_SWAP_LSBS,
80 FF_FFT_PERM_AVX,
81 };
82
83 enum mdct_permutation_type {
84 FF_MDCT_PERM_NONE,
85 FF_MDCT_PERM_INTERLEAVE,
86 };
87
88 struct FFTContext {
89 int nbits;
90 int inverse;
91 uint16_t *revtab;
92 FFTComplex *tmp_buf;
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 */
96 FFTSample *tcos;
97 FFTSample *tsin;
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);
111 enum fft_permutation_type fft_permutation;
112 enum mdct_permutation_type mdct_permutation;
113 };
114
115 #if CONFIG_HARDCODED_TABLES
116 #define COSTABLE_CONST const
117 #else
118 #define COSTABLE_CONST
119 #endif
120
121 #define COSTABLE(size) \
122 COSTABLE_CONST DECLARE_ALIGNED(32, FFTSample, FFT_NAME(ff_cos_##size))[size/2]
123
124 extern COSTABLE(16);
125 extern COSTABLE(32);
126 extern COSTABLE(64);
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];
138
139 #define ff_init_ff_cos_tabs FFT_NAME(ff_init_ff_cos_tabs)
140
141 /**
142 * Initialize the cosine table in ff_cos_tabs[index]
143 * @param index index in ff_cos_tabs array of the table to initialize
144 */
145 void ff_init_ff_cos_tabs(int index);
146
147 #define ff_fft_init FFT_NAME(ff_fft_init)
148 #define ff_fft_end FFT_NAME(ff_fft_end)
149
150 /**
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
154 */
155 int ff_fft_init(FFTContext *s, int nbits, int inverse);
156
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);
162
163 void ff_fft_fixed_init_arm(FFTContext *s);
164
165 void ff_fft_end(FFTContext *s);
166
167 #define ff_mdct_init FFT_NAME(ff_mdct_init)
168 #define ff_mdct_end FFT_NAME(ff_mdct_end)
169
170 int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
171 void ff_mdct_end(FFTContext *s);
172
173 #endif /* AVCODEC_FFT_H */