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
27 #include "libavutil/mem.h"
37 int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
38 int mdct_bits; /* n = 2^nbits */
39 /* pre/post rotation tables */
42 void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
43 void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
44 void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
45 void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
46 void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
48 #define FF_FFT_PERM_DEFAULT 0
49 #define FF_FFT_PERM_SWAP_LSBS 1
51 #define FF_MDCT_PERM_NONE 0
52 #define FF_MDCT_PERM_INTERLEAVE 1
55 #if CONFIG_HARDCODED_TABLES
56 #define COSTABLE_CONST const
57 #define SINTABLE_CONST const
58 #define SINETABLE_CONST const
60 #define COSTABLE_CONST
61 #define SINTABLE_CONST
62 #define SINETABLE_CONST
65 #define COSTABLE(size) \
66 COSTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_cos_##size)[size/2]
67 #define SINTABLE(size) \
68 SINTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_sin_##size)[size/2]
69 #define SINETABLE(size) \
70 SINETABLE_CONST DECLARE_ALIGNED(16, float, ff_sine_##size)[size]
77 extern COSTABLE(1024);
78 extern COSTABLE(2048);
79 extern COSTABLE(4096);
80 extern COSTABLE(8192);
81 extern COSTABLE(16384);
82 extern COSTABLE(32768);
83 extern COSTABLE(65536);
84 extern COSTABLE_CONST FFTSample* const ff_cos_tabs[17];
87 * Initialize the cosine table in ff_cos_tabs[index]
88 * \param index index in ff_cos_tabs array of the table to initialize
90 void ff_init_ff_cos_tabs(int index);
98 extern SINTABLE(1024);
99 extern SINTABLE(2048);
100 extern SINTABLE(4096);
101 extern SINTABLE(8192);
102 extern SINTABLE(16384);
103 extern SINTABLE(32768);
104 extern SINTABLE(65536);
107 * Set up a complex FFT.
108 * @param nbits log2 of the length of the input array
109 * @param inverse if 0 perform the forward transform, if 1 perform the inverse
111 int ff_fft_init(FFTContext *s, int nbits, int inverse);
113 void ff_fft_init_altivec(FFTContext *s);
114 void ff_fft_init_mmx(FFTContext *s);
115 void ff_fft_init_arm(FFTContext *s);
116 void ff_dct_init_mmx(DCTContext *s);
119 * Do the permutation needed BEFORE calling ff_fft_calc().
121 static inline void ff_fft_permute(FFTContext *s, FFTComplex *z)
123 s->fft_permute(s, z);
126 * Do a complex FFT with the parameters defined in ff_fft_init(). The
127 * input data must be permuted before. No 1.0/sqrt(n) normalization is done.
129 static inline void ff_fft_calc(FFTContext *s, FFTComplex *z)
133 void ff_fft_end(FFTContext *s);
135 /* MDCT computation */
137 static inline void ff_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
139 s->imdct_calc(s, output, input);
141 static inline void ff_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)
143 s->imdct_half(s, output, input);
146 static inline void ff_mdct_calc(FFTContext *s, FFTSample *output,
147 const FFTSample *input)
149 s->mdct_calc(s, output, input);
153 * Maximum window size for ff_kbd_window_init.
155 #define FF_KBD_WINDOW_MAX 1024
158 * Generate a Kaiser-Bessel Derived Window.
159 * @param window pointer to half window
160 * @param alpha determines window shape
161 * @param n size of half window, max FF_KBD_WINDOW_MAX
163 void ff_kbd_window_init(float *window, float alpha, int n);
166 * Generate a sine window.
167 * @param window pointer to half window
168 * @param n size of half window
170 void ff_sine_window_init(float *window, int n);
173 * initialize the specified entry of ff_sine_windows
175 void ff_init_ff_sine_windows(int index);
176 extern SINETABLE( 32);
177 extern SINETABLE( 64);
178 extern SINETABLE( 128);
179 extern SINETABLE( 256);
180 extern SINETABLE( 512);
181 extern SINETABLE(1024);
182 extern SINETABLE(2048);
183 extern SINETABLE(4096);
184 extern SINETABLE_CONST float * const ff_sine_windows[13];
186 int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
187 void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
188 void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input);
189 void ff_mdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
190 void ff_mdct_end(FFTContext *s);
192 /* Real Discrete Fourier Transform */
199 /* pre/post rotation tables */
200 const FFTSample *tcos;
201 SINTABLE_CONST FFTSample *tsin;
203 void (*rdft_calc)(struct RDFTContext *s, FFTSample *z);
208 * @param nbits log2 of the length of the input array
209 * @param trans the type of transform
211 int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans);
212 void ff_rdft_end(RDFTContext *s);
214 void ff_rdft_init_arm(RDFTContext *s);
216 static av_always_inline void ff_rdft_calc(RDFTContext *s, FFTSample *data)
218 s->rdft_calc(s, data);
221 /* Discrete Cosine Transform */
229 void (*dct_calc)(struct DCTContext *s, FFTSample *data);
230 void (*dct32)(FFTSample *out, const FFTSample *in);
235 * @param nbits size of the input array:
236 * (1 << nbits) for DCT-II, DCT-III and DST-I
237 * (1 << nbits) + 1 for DCT-I
239 * @note the first element of the input of DST-I is ignored
241 int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType type);
242 void ff_dct_calc(DCTContext *s, FFTSample *data);
243 void ff_dct_end (DCTContext *s);
245 #endif /* AVCODEC_FFT_H */