apps/codecs/libwmapro/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 #include <stdint.h>
  26 //#include "config.h"
  27 #include "libavutil/mem.h"
  28 #include "avfft.h"
  29
  30 /* FFT computation */
  31
  32 struct FFTContext {
  33     int nbits;
  34     int inverse;
  35     uint16_t *revtab;
  36     FFTComplex *exptab;
  37     FFTComplex *exptab1; /* only used by SSE code */
  38     FFTComplex *tmp_buf;
  39     int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
  40     int mdct_bits; /* n = 2^nbits */
  41     /* pre/post rotation tables */
  42     FFTSample *tcos;
  43     FFTSample *tsin;
  44     void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
  45     void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
  46     void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
  47     void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
  48     void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
  49     int split_radix;
  50     int permutation;
  51 #define FF_MDCT_PERM_NONE       0
  52 #define FF_MDCT_PERM_INTERLEAVE 1
  53 };
  54
  55 #if CONFIG_HARDCODED_TABLES
  56 #define COSTABLE_CONST const
  57 #define SINTABLE_CONST const
  58 #define SINETABLE_CONST const
  59 #else
  60 #define COSTABLE_CONST
  61 #define SINTABLE_CONST
  62 #define SINETABLE_CONST
  63 #endif
  64
  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]
  71 extern COSTABLE(16);
  72 extern COSTABLE(32);
  73 extern COSTABLE(64);
  74 extern COSTABLE(128);
  75 extern COSTABLE(256);
  76 extern COSTABLE(512);
  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];
  85
  86 /**
  87  * Initializes the cosine table in ff_cos_tabs[index]
  88  * \param index index in ff_cos_tabs array of the table to initialize
  89  */
  90 void ff_init_ff_cos_tabs(int index);
  91
  92 extern SINTABLE(16);
  93 extern SINTABLE(32);
  94 extern SINTABLE(64);
  95 extern SINTABLE(128);
  96 extern SINTABLE(256);
  97 extern SINTABLE(512);
  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);
 105
 106 /**
 107  * Sets 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
 110  */
 111 int ff_fft_init(FFTContext *s, int nbits, int inverse);
 112 void ff_fft_permute_c(FFTContext *s, FFTComplex *z);
 113 void ff_fft_calc_c(FFTContext *s, FFTComplex *z);
 114
 115 void ff_fft_init_altivec(FFTContext *s);
 116 void ff_fft_init_mmx(FFTContext *s);
 117 void ff_fft_init_arm(FFTContext *s);
 118
 119 /**
 120  * Do the permutation needed BEFORE calling ff_fft_calc().
 121  */
 122 static inline void ff_fft_permute(FFTContext *s, FFTComplex *z)
 123 {
 124     s->fft_permute(s, z);
 125 }
 126 /**
 127  * Do a complex FFT with the parameters defined in ff_fft_init(). The
 128  * input data must be permuted before. No 1.0/sqrt(n) normalization is done.
 129  */
 130 static inline void ff_fft_calc(FFTContext *s, FFTComplex *z)
 131 {
 132     s->fft_calc(s, z);
 133 }
 134 void ff_fft_end(FFTContext *s);
 135
 136 /* MDCT computation */
 137
 138 static inline void ff_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
 139 {
 140     s->imdct_calc(s, output, input);
 141 }
 142 static inline void ff_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)
 143 {
 144     s->imdct_half(s, output, input);
 145 }
 146
 147 static inline void ff_mdct_calc(FFTContext *s, FFTSample *output,
 148                                 const FFTSample *input)
 149 {
 150     s->mdct_calc(s, output, input);
 151 }
 152
 153 /**
 154  * Generate a Kaiser-Bessel Derived Window.
 155  * @param   window  pointer to half window
 156  * @param   alpha   determines window shape
 157  * @param   n       size of half window
 158  */
 159 void ff_kbd_window_init(float *window, float alpha, int n);
 160
 161 /**
 162  * Generate a sine window.
 163  * @param   window  pointer to half window
 164  * @param   n       size of half window
 165  */
 166 void ff_sine_window_init(float *window, int n);
 167
 168 /**
 169  * initialize the specified entry of ff_sine_windows
 170  */
 171 void ff_init_ff_sine_windows(int index);
 172 extern SINETABLE(  32);
 173 extern SINETABLE(  64);
 174 extern SINETABLE( 128);
 175 extern SINETABLE( 256);
 176 extern SINETABLE( 512);
 177 extern SINETABLE(1024);
 178 extern SINETABLE(2048);
 179 extern SINETABLE(4096);
 180 extern SINETABLE_CONST float * const ff_sine_windows[13];
 181
 182 int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
 183 void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
 184 void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input);
 185 void ff_mdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
 186 void ff_mdct_end(FFTContext *s);
 187
 188 /* Real Discrete Fourier Transform */
 189
 190 struct RDFTContext {
 191     int nbits;
 192     int inverse;
 193     int sign_convention;
 194
 195     /* pre/post rotation tables */
 196     const FFTSample *tcos;
 197     SINTABLE_CONST FFTSample *tsin;
 198     FFTContext fft;
 199     void (*rdft_calc)(struct RDFTContext *s, FFTSample *z);
 200 };
 201
 202 /**
 203  * Sets up a real FFT.
 204  * @param nbits           log2 of the length of the input array
 205  * @param trans           the type of transform
 206  */
 207 int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans);
 208 void ff_rdft_end(RDFTContext *s);
 209
 210 void ff_rdft_init_arm(RDFTContext *s);
 211
 212 static av_always_inline void ff_rdft_calc(RDFTContext *s, FFTSample *data)
 213 {
 214     s->rdft_calc(s, data);
 215 }
 216
 217 /* Discrete Cosine Transform */
 218
 219 struct DCTContext {
 220     int nbits;
 221     int inverse;
 222     RDFTContext rdft;
 223     const float *costab;
 224     FFTSample *csc2;
 225     void (*dct_calc)(struct DCTContext *s, FFTSample *data);
 226 };
 227
 228 /**
 229  * Sets up DCT.
 230  * @param nbits           size of the input array:
 231  *                        (1 << nbits)     for DCT-II, DCT-III and DST-I
 232  *                        (1 << nbits) + 1 for DCT-I
 233  *
 234  * @note the first element of the input of DST-I is ignored
 235  */
 236 int  ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType type);
 237 void ff_dct_calc(DCTContext *s, FFTSample *data);
 238 void ff_dct_end (DCTContext *s);
 239
 240 #endif /* AVCODEC_FFT_H */