FFmpeg  4.0
fft_template.c
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1 /*
2  * FFT/IFFT transforms
3  * Copyright (c) 2008 Loren Merritt
4  * Copyright (c) 2002 Fabrice Bellard
5  * Partly based on libdjbfft by D. J. Bernstein
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * FFT/IFFT transforms.
27  */
28 
29 #include <stdlib.h>
30 #include <string.h>
31 #include "libavutil/mathematics.h"
32 #include "libavutil/thread.h"
33 #include "fft.h"
34 #include "fft-internal.h"
35 
36 #if FFT_FIXED_32
37 #include "fft_table.h"
38 
39 static void av_cold fft_lut_init(void)
40 {
41  int n = 0;
42  ff_fft_lut_init(ff_fft_offsets_lut, 0, 1 << 17, &n);
43 }
44 
45 #else /* FFT_FIXED_32 */
46 
47 /* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */
48 #if !CONFIG_HARDCODED_TABLES
49 COSTABLE(16);
50 COSTABLE(32);
51 COSTABLE(64);
52 COSTABLE(128);
53 COSTABLE(256);
54 COSTABLE(512);
55 COSTABLE(1024);
56 COSTABLE(2048);
57 COSTABLE(4096);
58 COSTABLE(8192);
59 COSTABLE(16384);
60 COSTABLE(32768);
61 COSTABLE(65536);
62 COSTABLE(131072);
63 
64 static av_cold void init_ff_cos_tabs(int index)
65 {
66  int i;
67  int m = 1<<index;
68  double freq = 2*M_PI/m;
69  FFTSample *tab = FFT_NAME(ff_cos_tabs)[index];
70  for(i=0; i<=m/4; i++)
71  tab[i] = FIX15(cos(i*freq));
72  for(i=1; i<m/4; i++)
73  tab[m/2-i] = tab[i];
74 }
75 
76 typedef struct CosTabsInitOnce {
77  void (*func)(void);
80 
81 #define INIT_FF_COS_TABS_FUNC(index, size) \
82 static av_cold void init_ff_cos_tabs_ ## size (void)\
83 { \
84  init_ff_cos_tabs(index); \
85 }
86 
93 INIT_FF_COS_TABS_FUNC(10, 1024)
94 INIT_FF_COS_TABS_FUNC(11, 2048)
95 INIT_FF_COS_TABS_FUNC(12, 4096)
96 INIT_FF_COS_TABS_FUNC(13, 8192)
97 INIT_FF_COS_TABS_FUNC(14, 16384)
98 INIT_FF_COS_TABS_FUNC(15, 32768)
99 INIT_FF_COS_TABS_FUNC(16, 65536)
100 INIT_FF_COS_TABS_FUNC(17, 131072)
101 
103  { NULL },
104  { NULL },
105  { NULL },
106  { NULL },
107  { init_ff_cos_tabs_16, AV_ONCE_INIT },
108  { init_ff_cos_tabs_32, AV_ONCE_INIT },
109  { init_ff_cos_tabs_64, AV_ONCE_INIT },
110  { init_ff_cos_tabs_128, AV_ONCE_INIT },
111  { init_ff_cos_tabs_256, AV_ONCE_INIT },
112  { init_ff_cos_tabs_512, AV_ONCE_INIT },
113  { init_ff_cos_tabs_1024, AV_ONCE_INIT },
114  { init_ff_cos_tabs_2048, AV_ONCE_INIT },
115  { init_ff_cos_tabs_4096, AV_ONCE_INIT },
116  { init_ff_cos_tabs_8192, AV_ONCE_INIT },
117  { init_ff_cos_tabs_16384, AV_ONCE_INIT },
118  { init_ff_cos_tabs_32768, AV_ONCE_INIT },
119  { init_ff_cos_tabs_65536, AV_ONCE_INIT },
120  { init_ff_cos_tabs_131072, AV_ONCE_INIT },
121 };
122 
123 #endif
124 COSTABLE_CONST FFTSample * const FFT_NAME(ff_cos_tabs)[] = {
125  NULL, NULL, NULL, NULL,
126  FFT_NAME(ff_cos_16),
127  FFT_NAME(ff_cos_32),
128  FFT_NAME(ff_cos_64),
129  FFT_NAME(ff_cos_128),
130  FFT_NAME(ff_cos_256),
131  FFT_NAME(ff_cos_512),
132  FFT_NAME(ff_cos_1024),
133  FFT_NAME(ff_cos_2048),
134  FFT_NAME(ff_cos_4096),
135  FFT_NAME(ff_cos_8192),
136  FFT_NAME(ff_cos_16384),
137  FFT_NAME(ff_cos_32768),
138  FFT_NAME(ff_cos_65536),
139  FFT_NAME(ff_cos_131072),
140 };
141 
142 #endif /* FFT_FIXED_32 */
143 
144 static void fft_permute_c(FFTContext *s, FFTComplex *z);
145 static void fft_calc_c(FFTContext *s, FFTComplex *z);
146 
147 static int split_radix_permutation(int i, int n, int inverse)
148 {
149  int m;
150  if(n <= 2) return i&1;
151  m = n >> 1;
152  if(!(i&m)) return split_radix_permutation(i, m, inverse)*2;
153  m >>= 1;
154  if(inverse == !(i&m)) return split_radix_permutation(i, m, inverse)*4 + 1;
155  else return split_radix_permutation(i, m, inverse)*4 - 1;
156 }
157 
159 {
160 #if (!CONFIG_HARDCODED_TABLES) && (!FFT_FIXED_32)
162 #endif
163 }
164 
165 static const int avx_tab[] = {
166  0, 4, 1, 5, 8, 12, 9, 13, 2, 6, 3, 7, 10, 14, 11, 15
167 };
168 
169 static int is_second_half_of_fft32(int i, int n)
170 {
171  if (n <= 32)
172  return i >= 16;
173  else if (i < n/2)
174  return is_second_half_of_fft32(i, n/2);
175  else if (i < 3*n/4)
176  return is_second_half_of_fft32(i - n/2, n/4);
177  else
178  return is_second_half_of_fft32(i - 3*n/4, n/4);
179 }
180 
182 {
183  int i;
184  int n = 1 << s->nbits;
185 
186  for (i = 0; i < n; i += 16) {
187  int k;
188  if (is_second_half_of_fft32(i, n)) {
189  for (k = 0; k < 16; k++)
190  s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] =
191  i + avx_tab[k];
192 
193  } else {
194  for (k = 0; k < 16; k++) {
195  int j = i + k;
196  j = (j & ~7) | ((j >> 1) & 3) | ((j << 2) & 4);
197  s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] = j;
198  }
199  }
200  }
201 }
202 
203 av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
204 {
205  int i, j, n;
206 
207  s->revtab = NULL;
208  s->revtab32 = NULL;
209 
210  if (nbits < 2 || nbits > 17)
211  goto fail;
212  s->nbits = nbits;
213  n = 1 << nbits;
214 
215  if (nbits <= 16) {
216  s->revtab = av_malloc(n * sizeof(uint16_t));
217  if (!s->revtab)
218  goto fail;
219  } else {
220  s->revtab32 = av_malloc(n * sizeof(uint32_t));
221  if (!s->revtab32)
222  goto fail;
223  }
224  s->tmp_buf = av_malloc(n * sizeof(FFTComplex));
225  if (!s->tmp_buf)
226  goto fail;
227  s->inverse = inverse;
229 
231  s->fft_calc = fft_calc_c;
232 #if CONFIG_MDCT
236 #endif
237 
238 #if FFT_FIXED_32
239  {
240  static AVOnce control = AV_ONCE_INIT;
241  ff_thread_once(&control, fft_lut_init);
242  }
243 #else /* FFT_FIXED_32 */
244 #if FFT_FLOAT
246  if (ARCH_ARM) ff_fft_init_arm(s);
247  if (ARCH_PPC) ff_fft_init_ppc(s);
248  if (ARCH_X86) ff_fft_init_x86(s);
249  if (CONFIG_MDCT) s->mdct_calcw = s->mdct_calc;
251 #else
254 #endif
255  for(j=4; j<=nbits; j++) {
257  }
258 #endif /* FFT_FIXED_32 */
259 
260 
261  if (s->fft_permutation == FF_FFT_PERM_AVX) {
262  fft_perm_avx(s);
263  } else {
264  for(i=0; i<n; i++) {
265  int k;
266  j = i;
268  j = (j&~3) | ((j>>1)&1) | ((j<<1)&2);
269  k = -split_radix_permutation(i, n, s->inverse) & (n-1);
270  if (s->revtab)
271  s->revtab[k] = j;
272  if (s->revtab32)
273  s->revtab32[k] = j;
274  }
275  }
276 
277  return 0;
278  fail:
279  av_freep(&s->revtab);
280  av_freep(&s->revtab32);
281  av_freep(&s->tmp_buf);
282  return -1;
283 }
284 
286 {
287  int j, np;
288  const uint16_t *revtab = s->revtab;
289  const uint32_t *revtab32 = s->revtab32;
290  np = 1 << s->nbits;
291  /* TODO: handle split-radix permute in a more optimal way, probably in-place */
292  if (revtab) {
293  for(j=0;j<np;j++) s->tmp_buf[revtab[j]] = z[j];
294  } else
295  for(j=0;j<np;j++) s->tmp_buf[revtab32[j]] = z[j];
296 
297  memcpy(z, s->tmp_buf, np * sizeof(FFTComplex));
298 }
299 
301 {
302  av_freep(&s->revtab);
303  av_freep(&s->revtab32);
304  av_freep(&s->tmp_buf);
305 }
306 
307 #if FFT_FIXED_32
308 
309 static void fft_calc_c(FFTContext *s, FFTComplex *z) {
310 
311  int nbits, i, n, num_transforms, offset, step;
312  int n4, n2, n34;
313  unsigned tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
314  FFTComplex *tmpz;
315  const int fft_size = (1 << s->nbits);
316  int64_t accu;
317 
318  num_transforms = (0x2aab >> (16 - s->nbits)) | 1;
319 
320  for (n=0; n<num_transforms; n++){
321  offset = ff_fft_offsets_lut[n] << 2;
322  tmpz = z + offset;
323 
324  tmp1 = tmpz[0].re + (unsigned)tmpz[1].re;
325  tmp5 = tmpz[2].re + (unsigned)tmpz[3].re;
326  tmp2 = tmpz[0].im + (unsigned)tmpz[1].im;
327  tmp6 = tmpz[2].im + (unsigned)tmpz[3].im;
328  tmp3 = tmpz[0].re - (unsigned)tmpz[1].re;
329  tmp8 = tmpz[2].im - (unsigned)tmpz[3].im;
330  tmp4 = tmpz[0].im - (unsigned)tmpz[1].im;
331  tmp7 = tmpz[2].re - (unsigned)tmpz[3].re;
332 
333  tmpz[0].re = tmp1 + tmp5;
334  tmpz[2].re = tmp1 - tmp5;
335  tmpz[0].im = tmp2 + tmp6;
336  tmpz[2].im = tmp2 - tmp6;
337  tmpz[1].re = tmp3 + tmp8;
338  tmpz[3].re = tmp3 - tmp8;
339  tmpz[1].im = tmp4 - tmp7;
340  tmpz[3].im = tmp4 + tmp7;
341  }
342 
343  if (fft_size < 8)
344  return;
345 
346  num_transforms = (num_transforms >> 1) | 1;
347 
348  for (n=0; n<num_transforms; n++){
349  offset = ff_fft_offsets_lut[n] << 3;
350  tmpz = z + offset;
351 
352  tmp1 = tmpz[4].re + (unsigned)tmpz[5].re;
353  tmp3 = tmpz[6].re + (unsigned)tmpz[7].re;
354  tmp2 = tmpz[4].im + (unsigned)tmpz[5].im;
355  tmp4 = tmpz[6].im + (unsigned)tmpz[7].im;
356  tmp5 = tmp1 + tmp3;
357  tmp7 = tmp1 - tmp3;
358  tmp6 = tmp2 + tmp4;
359  tmp8 = tmp2 - tmp4;
360 
361  tmp1 = tmpz[4].re - (unsigned)tmpz[5].re;
362  tmp2 = tmpz[4].im - (unsigned)tmpz[5].im;
363  tmp3 = tmpz[6].re - (unsigned)tmpz[7].re;
364  tmp4 = tmpz[6].im - (unsigned)tmpz[7].im;
365 
366  tmpz[4].re = tmpz[0].re - tmp5;
367  tmpz[0].re = tmpz[0].re + tmp5;
368  tmpz[4].im = tmpz[0].im - tmp6;
369  tmpz[0].im = tmpz[0].im + tmp6;
370  tmpz[6].re = tmpz[2].re - tmp8;
371  tmpz[2].re = tmpz[2].re + tmp8;
372  tmpz[6].im = tmpz[2].im + tmp7;
373  tmpz[2].im = tmpz[2].im - tmp7;
374 
375  accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp1 + tmp2);
376  tmp5 = (int32_t)((accu + 0x40000000) >> 31);
377  accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 - tmp4);
378  tmp7 = (int32_t)((accu + 0x40000000) >> 31);
379  accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp2 - tmp1);
380  tmp6 = (int32_t)((accu + 0x40000000) >> 31);
381  accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 + tmp4);
382  tmp8 = (int32_t)((accu + 0x40000000) >> 31);
383  tmp1 = tmp5 + tmp7;
384  tmp3 = tmp5 - tmp7;
385  tmp2 = tmp6 + tmp8;
386  tmp4 = tmp6 - tmp8;
387 
388  tmpz[5].re = tmpz[1].re - tmp1;
389  tmpz[1].re = tmpz[1].re + tmp1;
390  tmpz[5].im = tmpz[1].im - tmp2;
391  tmpz[1].im = tmpz[1].im + tmp2;
392  tmpz[7].re = tmpz[3].re - tmp4;
393  tmpz[3].re = tmpz[3].re + tmp4;
394  tmpz[7].im = tmpz[3].im + tmp3;
395  tmpz[3].im = tmpz[3].im - tmp3;
396  }
397 
398  step = 1 << ((MAX_LOG2_NFFT-4) - 4);
399  n4 = 4;
400 
401  for (nbits=4; nbits<=s->nbits; nbits++){
402  n2 = 2*n4;
403  n34 = 3*n4;
404  num_transforms = (num_transforms >> 1) | 1;
405 
406  for (n=0; n<num_transforms; n++){
407  const FFTSample *w_re_ptr = ff_w_tab_sr + step;
408  const FFTSample *w_im_ptr = ff_w_tab_sr + MAX_FFT_SIZE/(4*16) - step;
409  offset = ff_fft_offsets_lut[n] << nbits;
410  tmpz = z + offset;
411 
412  tmp5 = tmpz[ n2].re + (unsigned)tmpz[n34].re;
413  tmp1 = tmpz[ n2].re - (unsigned)tmpz[n34].re;
414  tmp6 = tmpz[ n2].im + (unsigned)tmpz[n34].im;
415  tmp2 = tmpz[ n2].im - (unsigned)tmpz[n34].im;
416 
417  tmpz[ n2].re = tmpz[ 0].re - tmp5;
418  tmpz[ 0].re = tmpz[ 0].re + tmp5;
419  tmpz[ n2].im = tmpz[ 0].im - tmp6;
420  tmpz[ 0].im = tmpz[ 0].im + tmp6;
421  tmpz[n34].re = tmpz[n4].re - tmp2;
422  tmpz[ n4].re = tmpz[n4].re + tmp2;
423  tmpz[n34].im = tmpz[n4].im + tmp1;
424  tmpz[ n4].im = tmpz[n4].im - tmp1;
425 
426  for (i=1; i<n4; i++){
427  FFTSample w_re = w_re_ptr[0];
428  FFTSample w_im = w_im_ptr[0];
429  accu = (int64_t)w_re*tmpz[ n2+i].re;
430  accu += (int64_t)w_im*tmpz[ n2+i].im;
431  tmp1 = (int32_t)((accu + 0x40000000) >> 31);
432  accu = (int64_t)w_re*tmpz[ n2+i].im;
433  accu -= (int64_t)w_im*tmpz[ n2+i].re;
434  tmp2 = (int32_t)((accu + 0x40000000) >> 31);
435  accu = (int64_t)w_re*tmpz[n34+i].re;
436  accu -= (int64_t)w_im*tmpz[n34+i].im;
437  tmp3 = (int32_t)((accu + 0x40000000) >> 31);
438  accu = (int64_t)w_re*tmpz[n34+i].im;
439  accu += (int64_t)w_im*tmpz[n34+i].re;
440  tmp4 = (int32_t)((accu + 0x40000000) >> 31);
441 
442  tmp5 = tmp1 + tmp3;
443  tmp1 = tmp1 - tmp3;
444  tmp6 = tmp2 + tmp4;
445  tmp2 = tmp2 - tmp4;
446 
447  tmpz[ n2+i].re = tmpz[ i].re - tmp5;
448  tmpz[ i].re = tmpz[ i].re + tmp5;
449  tmpz[ n2+i].im = tmpz[ i].im - tmp6;
450  tmpz[ i].im = tmpz[ i].im + tmp6;
451  tmpz[n34+i].re = tmpz[n4+i].re - tmp2;
452  tmpz[ n4+i].re = tmpz[n4+i].re + tmp2;
453  tmpz[n34+i].im = tmpz[n4+i].im + tmp1;
454  tmpz[ n4+i].im = tmpz[n4+i].im - tmp1;
455 
456  w_re_ptr += step;
457  w_im_ptr -= step;
458  }
459  }
460  step >>= 1;
461  n4 <<= 1;
462  }
463 }
464 
465 #else /* FFT_FIXED_32 */
466 
467 #define BUTTERFLIES(a0,a1,a2,a3) {\
468  BF(t3, t5, t5, t1);\
469  BF(a2.re, a0.re, a0.re, t5);\
470  BF(a3.im, a1.im, a1.im, t3);\
471  BF(t4, t6, t2, t6);\
472  BF(a3.re, a1.re, a1.re, t4);\
473  BF(a2.im, a0.im, a0.im, t6);\
474 }
475 
476 // force loading all the inputs before storing any.
477 // this is slightly slower for small data, but avoids store->load aliasing
478 // for addresses separated by large powers of 2.
479 #define BUTTERFLIES_BIG(a0,a1,a2,a3) {\
480  FFTSample r0=a0.re, i0=a0.im, r1=a1.re, i1=a1.im;\
481  BF(t3, t5, t5, t1);\
482  BF(a2.re, a0.re, r0, t5);\
483  BF(a3.im, a1.im, i1, t3);\
484  BF(t4, t6, t2, t6);\
485  BF(a3.re, a1.re, r1, t4);\
486  BF(a2.im, a0.im, i0, t6);\
487 }
488 
489 #define TRANSFORM(a0,a1,a2,a3,wre,wim) {\
490  CMUL(t1, t2, a2.re, a2.im, wre, -wim);\
491  CMUL(t5, t6, a3.re, a3.im, wre, wim);\
492  BUTTERFLIES(a0,a1,a2,a3)\
493 }
494 
495 #define TRANSFORM_ZERO(a0,a1,a2,a3) {\
496  t1 = a2.re;\
497  t2 = a2.im;\
498  t5 = a3.re;\
499  t6 = a3.im;\
500  BUTTERFLIES(a0,a1,a2,a3)\
501 }
502 
503 /* z[0...8n-1], w[1...2n-1] */
504 #define PASS(name)\
505 static void name(FFTComplex *z, const FFTSample *wre, unsigned int n)\
506 {\
507  FFTDouble t1, t2, t3, t4, t5, t6;\
508  int o1 = 2*n;\
509  int o2 = 4*n;\
510  int o3 = 6*n;\
511  const FFTSample *wim = wre+o1;\
512  n--;\
513 \
514  TRANSFORM_ZERO(z[0],z[o1],z[o2],z[o3]);\
515  TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
516  do {\
517  z += 2;\
518  wre += 2;\
519  wim -= 2;\
520  TRANSFORM(z[0],z[o1],z[o2],z[o3],wre[0],wim[0]);\
521  TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
522  } while(--n);\
523 }
524 
525 PASS(pass)
526 #undef BUTTERFLIES
527 #define BUTTERFLIES BUTTERFLIES_BIG
528 PASS(pass_big)
529 
530 #define DECL_FFT(n,n2,n4)\
531 static void fft##n(FFTComplex *z)\
532 {\
533  fft##n2(z);\
534  fft##n4(z+n4*2);\
535  fft##n4(z+n4*3);\
536  pass(z,FFT_NAME(ff_cos_##n),n4/2);\
537 }
538 
539 static void fft4(FFTComplex *z)
540 {
541  FFTDouble t1, t2, t3, t4, t5, t6, t7, t8;
542 
543  BF(t3, t1, z[0].re, z[1].re);
544  BF(t8, t6, z[3].re, z[2].re);
545  BF(z[2].re, z[0].re, t1, t6);
546  BF(t4, t2, z[0].im, z[1].im);
547  BF(t7, t5, z[2].im, z[3].im);
548  BF(z[3].im, z[1].im, t4, t8);
549  BF(z[3].re, z[1].re, t3, t7);
550  BF(z[2].im, z[0].im, t2, t5);
551 }
552 
553 static void fft8(FFTComplex *z)
554 {
555  FFTDouble t1, t2, t3, t4, t5, t6;
556 
557  fft4(z);
558 
559  BF(t1, z[5].re, z[4].re, -z[5].re);
560  BF(t2, z[5].im, z[4].im, -z[5].im);
561  BF(t5, z[7].re, z[6].re, -z[7].re);
562  BF(t6, z[7].im, z[6].im, -z[7].im);
563 
564  BUTTERFLIES(z[0],z[2],z[4],z[6]);
565  TRANSFORM(z[1],z[3],z[5],z[7],sqrthalf,sqrthalf);
566 }
567 
568 #if !CONFIG_SMALL
569 static void fft16(FFTComplex *z)
570 {
571  FFTDouble t1, t2, t3, t4, t5, t6;
572  FFTSample cos_16_1 = FFT_NAME(ff_cos_16)[1];
573  FFTSample cos_16_3 = FFT_NAME(ff_cos_16)[3];
574 
575  fft8(z);
576  fft4(z+8);
577  fft4(z+12);
578 
579  TRANSFORM_ZERO(z[0],z[4],z[8],z[12]);
580  TRANSFORM(z[2],z[6],z[10],z[14],sqrthalf,sqrthalf);
581  TRANSFORM(z[1],z[5],z[9],z[13],cos_16_1,cos_16_3);
582  TRANSFORM(z[3],z[7],z[11],z[15],cos_16_3,cos_16_1);
583 }
584 #else
585 DECL_FFT(16,8,4)
586 #endif
587 DECL_FFT(32,16,8)
588 DECL_FFT(64,32,16)
589 DECL_FFT(128,64,32)
590 DECL_FFT(256,128,64)
591 DECL_FFT(512,256,128)
592 #if !CONFIG_SMALL
593 #define pass pass_big
594 #endif
595 DECL_FFT(1024,512,256)
596 DECL_FFT(2048,1024,512)
597 DECL_FFT(4096,2048,1024)
598 DECL_FFT(8192,4096,2048)
599 DECL_FFT(16384,8192,4096)
600 DECL_FFT(32768,16384,8192)
601 DECL_FFT(65536,32768,16384)
602 DECL_FFT(131072,65536,32768)
603 
604 static void (* const fft_dispatch[])(FFTComplex*) = {
605  fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512, fft1024,
606  fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072
607 };
608 
609 static void fft_calc_c(FFTContext *s, FFTComplex *z)
610 {
611  fft_dispatch[s->nbits-2](z);
612 }
613 #endif /* FFT_FIXED_32 */
static void fft_permute_c(FFTContext *s, FFTComplex *z)
Definition: fft_template.c:285
#define NULL
Definition: coverity.c:32
#define MAX_FFT_SIZE
Definition: fft_table.h:60
#define BUTTERFLIES(a0, a1, a2, a3)
Definition: fft_template.c:527
float FFTDouble
Definition: fft.h:43
const char * s
Definition: avisynth_c.h:768
static CosTabsInitOnce cos_tabs_init_once[]
Definition: fft_template.c:102
float re
Definition: fft.c:82
#define ARCH_PPC
Definition: config.h:29
#define M_SQRT1_2
Definition: mathematics.h:58
static const int avx_tab[]
Definition: fft_template.c:165
FFTSample re
Definition: avfft.h:38
#define t8
Definition: regdef.h:53
static int split_radix_permutation(int i, int n, int inverse)
Definition: fft_template.c:147
#define MAX_LOG2_NFFT
Specifies maximum allowed fft size.
Definition: fft_table.h:59
#define sqrthalf
Definition: fft-internal.h:64
#define t7
Definition: regdef.h:35
void ff_fft_lut_init(uint16_t *table, int off, int size, int *index)
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
COSTABLE(16)
av_cold void ff_fft_init_arm(FFTContext *s)
Definition: fft_init_arm.c:38
void ff_fft_init_ppc(FFTContext *s)
Definition: fft_init.c:151
const int32_t ff_w_tab_sr[MAX_FFT_SIZE/(4 *16)]
#define DECL_FFT(n, n2, n4)
Definition: fft_template.c:530
#define AVOnce
Definition: thread.h:159
#define INIT_FF_COS_TABS_FUNC(index, size)
Definition: fft_template.c:81
static void(*const fft_dispatch[])(FFTComplex *)
Definition: fft_template.c:604
#define FIX15(a)
Definition: fft-internal.h:62
void(* fft_permute)(struct FFTContext *s, FFTComplex *z)
Do the permutation needed BEFORE calling fft_calc().
Definition: fft.h:101
#define ARCH_X86
Definition: config.h:38
void(* mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input)
Definition: fft.h:110
void(* func)(void)
Definition: fft_template.c:77
#define t1
Definition: regdef.h:29
void(* mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:109
void(* imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:107
#define t3
Definition: regdef.h:31
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
av_cold void ff_fft_fixed_init_arm(FFTContext *s)
float FFTSample
Definition: avfft.h:35
#define fail()
Definition: checkasm.h:116
static av_cold void fft_perm_avx(FFTContext *s)
Definition: fft_template.c:181
#define pass
Definition: fft_template.c:593
#define Q31(x)
Definition: aac_defines.h:96
Definition: fft.h:88
av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
Set up a complex FFT.
Definition: fft_template.c:203
uint32_t * revtab32
Definition: fft.h:113
#define ARCH_ARM
Definition: config.h:19
#define PASS(name)
Definition: fft_template.c:504
int nbits
Definition: fft.h:89
int inverse
Definition: fft.h:90
int32_t
int n
Definition: avisynth_c.h:684
enum fft_permutation_type fft_permutation
Definition: fft.h:111
#define ff_imdct_half_c
Definition: fft-internal.h:87
#define ff_imdct_calc_c
Definition: fft-internal.h:86
static int is_second_half_of_fft32(int i, int n)
Definition: fft_template.c:169
#define AV_ONCE_INIT
Definition: thread.h:160
typedef void(RENAME(mix_any_func_type))
int index
Definition: gxfenc.c:89
float im
Definition: fft.c:82
uint16_t ff_fft_offsets_lut[21845]
#define t5
Definition: regdef.h:33
static av_cold void init_ff_cos_tabs(int index)
Definition: fft_template.c:64
void(* imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:108
#define TRANSFORM(a0, a1, a2, a3, wre, wim)
Definition: fft_template.c:489
#define TRANSFORM_ZERO(a0, a1, a2, a3)
Definition: fft_template.c:495
static void fft4(FFTComplex *z)
Definition: fft_template.c:539
#define CONFIG_MDCT
Definition: config.h:555
int
av_cold void ff_fft_end(FFTContext *s)
Definition: fft_template.c:300
FFTSample im
Definition: avfft.h:38
#define t6
Definition: regdef.h:34
void ff_mdct_calcw_c(FFTContext *s, FFTDouble *output, const FFTSample *input)
Definition: mdct_fixed.c:24
#define COSTABLE_CONST
Definition: fft.h:119
av_cold void ff_fft_init_aarch64(FFTContext *s)
void(* fft_calc)(struct FFTContext *s, FFTComplex *z)
Do a complex FFT with the parameters defined in ff_fft_init().
Definition: fft.h:106
#define t4
Definition: regdef.h:32
void ff_fft_init_mips(FFTContext *s)
FFT transform.
Definition: fft_mips.c:501
#define BF(a, b, c, s)
#define ff_mdct_calc_c
Definition: fft-internal.h:88
#define HAVE_MIPSFPU
Definition: config.h:74
static int ff_thread_once(char *control, void(*routine)(void))
Definition: thread.h:162
static void fft8(FFTComplex *z)
Definition: fft_template.c:553
COSTABLE_CONST FFTSample *const FFT_NAME(ff_cos_tabs)[]
static const struct twinvq_data tab
#define ARCH_AARCH64
Definition: config.h:17
#define av_freep(p)
uint16_t * revtab
Definition: fft.h:91
#define M_PI
Definition: mathematics.h:52
static uint32_t inverse(uint32_t v)
find multiplicative inverse modulo 2 ^ 32
Definition: asfcrypt.c:35
av_cold void ff_init_ff_cos_tabs(int index)
Initialize the cosine table in ff_cos_tabs[index].
Definition: fft_template.c:158
static void fft_calc_c(FFTContext *s, FFTComplex *z)
Definition: fft_template.c:609
static void fft16(FFTComplex *z)
Definition: fft_template.c:569
#define t2
Definition: regdef.h:30
definitions and tables for FFT
void ff_fft_init_x86(FFTContext *s)
Definition: fft_init.c:27
FFTComplex * tmp_buf
Definition: fft.h:92