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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 "fft.h"
33 #include "fft-internal.h"
34 
35 #if FFT_FIXED_32
36 #include "fft_table.h"
37 #else /* FFT_FIXED_32 */
38 
39 /* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */
40 #if !CONFIG_HARDCODED_TABLES
41 COSTABLE(16);
42 COSTABLE(32);
43 COSTABLE(64);
44 COSTABLE(128);
45 COSTABLE(256);
46 COSTABLE(512);
47 COSTABLE(1024);
48 COSTABLE(2048);
49 COSTABLE(4096);
50 COSTABLE(8192);
51 COSTABLE(16384);
52 COSTABLE(32768);
53 COSTABLE(65536);
54 COSTABLE(131072);
55 #endif
56 COSTABLE_CONST FFTSample * const FFT_NAME(ff_cos_tabs)[] = {
57  NULL, NULL, NULL, NULL,
58  FFT_NAME(ff_cos_16),
59  FFT_NAME(ff_cos_32),
60  FFT_NAME(ff_cos_64),
61  FFT_NAME(ff_cos_128),
62  FFT_NAME(ff_cos_256),
63  FFT_NAME(ff_cos_512),
64  FFT_NAME(ff_cos_1024),
65  FFT_NAME(ff_cos_2048),
66  FFT_NAME(ff_cos_4096),
67  FFT_NAME(ff_cos_8192),
68  FFT_NAME(ff_cos_16384),
69  FFT_NAME(ff_cos_32768),
70  FFT_NAME(ff_cos_65536),
71  FFT_NAME(ff_cos_131072),
72 };
73 
74 #endif /* FFT_FIXED_32 */
75 
76 static void fft_permute_c(FFTContext *s, FFTComplex *z);
77 static void fft_calc_c(FFTContext *s, FFTComplex *z);
78 
79 static int split_radix_permutation(int i, int n, int inverse)
80 {
81  int m;
82  if(n <= 2) return i&1;
83  m = n >> 1;
84  if(!(i&m)) return split_radix_permutation(i, m, inverse)*2;
85  m >>= 1;
86  if(inverse == !(i&m)) return split_radix_permutation(i, m, inverse)*4 + 1;
87  else return split_radix_permutation(i, m, inverse)*4 - 1;
88 }
89 
91 {
92 #if (!CONFIG_HARDCODED_TABLES) && (!FFT_FIXED_32)
93  int i;
94  int m = 1<<index;
95  double freq = 2*M_PI/m;
96  FFTSample *tab = FFT_NAME(ff_cos_tabs)[index];
97  for(i=0; i<=m/4; i++)
98  tab[i] = FIX15(cos(i*freq));
99  for(i=1; i<m/4; i++)
100  tab[m/2-i] = tab[i];
101 #endif
102 }
103 
104 static const int avx_tab[] = {
105  0, 4, 1, 5, 8, 12, 9, 13, 2, 6, 3, 7, 10, 14, 11, 15
106 };
107 
108 static int is_second_half_of_fft32(int i, int n)
109 {
110  if (n <= 32)
111  return i >= 16;
112  else if (i < n/2)
113  return is_second_half_of_fft32(i, n/2);
114  else if (i < 3*n/4)
115  return is_second_half_of_fft32(i - n/2, n/4);
116  else
117  return is_second_half_of_fft32(i - 3*n/4, n/4);
118 }
119 
121 {
122  int i;
123  int n = 1 << s->nbits;
124 
125  for (i = 0; i < n; i += 16) {
126  int k;
127  if (is_second_half_of_fft32(i, n)) {
128  for (k = 0; k < 16; k++)
129  s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] =
130  i + avx_tab[k];
131 
132  } else {
133  for (k = 0; k < 16; k++) {
134  int j = i + k;
135  j = (j & ~7) | ((j >> 1) & 3) | ((j << 2) & 4);
136  s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] = j;
137  }
138  }
139  }
140 }
141 
143 {
144  int i, j, n;
145 
146  s->revtab = NULL;
147  s->revtab32 = NULL;
148 
149  if (nbits < 2 || nbits > 17)
150  goto fail;
151  s->nbits = nbits;
152  n = 1 << nbits;
153 
154  if (nbits <= 16) {
155  s->revtab = av_malloc(n * sizeof(uint16_t));
156  if (!s->revtab)
157  goto fail;
158  } else {
159  s->revtab32 = av_malloc(n * sizeof(uint32_t));
160  if (!s->revtab32)
161  goto fail;
162  }
163  s->tmp_buf = av_malloc(n * sizeof(FFTComplex));
164  if (!s->tmp_buf)
165  goto fail;
166  s->inverse = inverse;
168 
170  s->fft_calc = fft_calc_c;
171 #if CONFIG_MDCT
175 #endif
176 
177 #if FFT_FIXED_32
178  {
179  int n=0;
180  ff_fft_lut_init(ff_fft_offsets_lut, 0, 1 << 17, &n);
181  }
182 #else /* FFT_FIXED_32 */
183 #if FFT_FLOAT
184  if (ARCH_AARCH64) ff_fft_init_aarch64(s);
185  if (ARCH_ARM) ff_fft_init_arm(s);
186  if (ARCH_PPC) ff_fft_init_ppc(s);
187  if (ARCH_X86) ff_fft_init_x86(s);
188  if (CONFIG_MDCT) s->mdct_calcw = s->mdct_calc;
189  if (HAVE_MIPSFPU) ff_fft_init_mips(s);
190 #else
191  if (CONFIG_MDCT) s->mdct_calcw = ff_mdct_calcw_c;
192  if (ARCH_ARM) ff_fft_fixed_init_arm(s);
193 #endif
194  for(j=4; j<=nbits; j++) {
196  }
197 #endif /* FFT_FIXED_32 */
198 
199 
200  if (s->fft_permutation == FF_FFT_PERM_AVX) {
201  fft_perm_avx(s);
202  } else {
203  for(i=0; i<n; i++) {
204  int k;
205  j = i;
207  j = (j&~3) | ((j>>1)&1) | ((j<<1)&2);
208  k = -split_radix_permutation(i, n, s->inverse) & (n-1);
209  if (s->revtab)
210  s->revtab[k] = j;
211  if (s->revtab32)
212  s->revtab32[k] = j;
213  }
214  }
215 
216  return 0;
217  fail:
218  av_freep(&s->revtab);
219  av_freep(&s->revtab32);
220  av_freep(&s->tmp_buf);
221  return -1;
222 }
223 
225 {
226  int j, np;
227  const uint16_t *revtab = s->revtab;
228  const uint32_t *revtab32 = s->revtab32;
229  np = 1 << s->nbits;
230  /* TODO: handle split-radix permute in a more optimal way, probably in-place */
231  if (revtab) {
232  for(j=0;j<np;j++) s->tmp_buf[revtab[j]] = z[j];
233  } else
234  for(j=0;j<np;j++) s->tmp_buf[revtab32[j]] = z[j];
235 
236  memcpy(z, s->tmp_buf, np * sizeof(FFTComplex));
237 }
238 
240 {
241  av_freep(&s->revtab);
242  av_freep(&s->revtab32);
243  av_freep(&s->tmp_buf);
244 }
245 
246 #if FFT_FIXED_32
247 
248 static void fft_calc_c(FFTContext *s, FFTComplex *z) {
249 
250  int nbits, i, n, num_transforms, offset, step;
251  int n4, n2, n34;
252  FFTSample tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
253  FFTComplex *tmpz;
254  const int fft_size = (1 << s->nbits);
255  int64_t accu;
256 
257  num_transforms = (0x2aab >> (16 - s->nbits)) | 1;
258 
259  for (n=0; n<num_transforms; n++){
260  offset = ff_fft_offsets_lut[n] << 2;
261  tmpz = z + offset;
262 
263  tmp1 = tmpz[0].re + tmpz[1].re;
264  tmp5 = tmpz[2].re + tmpz[3].re;
265  tmp2 = tmpz[0].im + tmpz[1].im;
266  tmp6 = tmpz[2].im + tmpz[3].im;
267  tmp3 = tmpz[0].re - tmpz[1].re;
268  tmp8 = tmpz[2].im - tmpz[3].im;
269  tmp4 = tmpz[0].im - tmpz[1].im;
270  tmp7 = tmpz[2].re - tmpz[3].re;
271 
272  tmpz[0].re = tmp1 + tmp5;
273  tmpz[2].re = tmp1 - tmp5;
274  tmpz[0].im = tmp2 + tmp6;
275  tmpz[2].im = tmp2 - tmp6;
276  tmpz[1].re = tmp3 + tmp8;
277  tmpz[3].re = tmp3 - tmp8;
278  tmpz[1].im = tmp4 - tmp7;
279  tmpz[3].im = tmp4 + tmp7;
280  }
281 
282  if (fft_size < 8)
283  return;
284 
285  num_transforms = (num_transforms >> 1) | 1;
286 
287  for (n=0; n<num_transforms; n++){
288  offset = ff_fft_offsets_lut[n] << 3;
289  tmpz = z + offset;
290 
291  tmp1 = tmpz[4].re + tmpz[5].re;
292  tmp3 = tmpz[6].re + tmpz[7].re;
293  tmp2 = tmpz[4].im + tmpz[5].im;
294  tmp4 = tmpz[6].im + tmpz[7].im;
295  tmp5 = tmp1 + tmp3;
296  tmp7 = tmp1 - tmp3;
297  tmp6 = tmp2 + tmp4;
298  tmp8 = tmp2 - tmp4;
299 
300  tmp1 = tmpz[4].re - tmpz[5].re;
301  tmp2 = tmpz[4].im - tmpz[5].im;
302  tmp3 = tmpz[6].re - tmpz[7].re;
303  tmp4 = tmpz[6].im - tmpz[7].im;
304 
305  tmpz[4].re = tmpz[0].re - tmp5;
306  tmpz[0].re = tmpz[0].re + tmp5;
307  tmpz[4].im = tmpz[0].im - tmp6;
308  tmpz[0].im = tmpz[0].im + tmp6;
309  tmpz[6].re = tmpz[2].re - tmp8;
310  tmpz[2].re = tmpz[2].re + tmp8;
311  tmpz[6].im = tmpz[2].im + tmp7;
312  tmpz[2].im = tmpz[2].im - tmp7;
313 
314  accu = (int64_t)Q31(M_SQRT1_2)*(tmp1 + tmp2);
315  tmp5 = (int32_t)((accu + 0x40000000) >> 31);
316  accu = (int64_t)Q31(M_SQRT1_2)*(tmp3 - tmp4);
317  tmp7 = (int32_t)((accu + 0x40000000) >> 31);
318  accu = (int64_t)Q31(M_SQRT1_2)*(tmp2 - tmp1);
319  tmp6 = (int32_t)((accu + 0x40000000) >> 31);
320  accu = (int64_t)Q31(M_SQRT1_2)*(tmp3 + tmp4);
321  tmp8 = (int32_t)((accu + 0x40000000) >> 31);
322  tmp1 = tmp5 + tmp7;
323  tmp3 = tmp5 - tmp7;
324  tmp2 = tmp6 + tmp8;
325  tmp4 = tmp6 - tmp8;
326 
327  tmpz[5].re = tmpz[1].re - tmp1;
328  tmpz[1].re = tmpz[1].re + tmp1;
329  tmpz[5].im = tmpz[1].im - tmp2;
330  tmpz[1].im = tmpz[1].im + tmp2;
331  tmpz[7].re = tmpz[3].re - tmp4;
332  tmpz[3].re = tmpz[3].re + tmp4;
333  tmpz[7].im = tmpz[3].im + tmp3;
334  tmpz[3].im = tmpz[3].im - tmp3;
335  }
336 
337  step = 1 << ((MAX_LOG2_NFFT-4) - 4);
338  n4 = 4;
339 
340  for (nbits=4; nbits<=s->nbits; nbits++){
341  n2 = 2*n4;
342  n34 = 3*n4;
343  num_transforms = (num_transforms >> 1) | 1;
344 
345  for (n=0; n<num_transforms; n++){
346  const FFTSample *w_re_ptr = ff_w_tab_sr + step;
347  const FFTSample *w_im_ptr = ff_w_tab_sr + MAX_FFT_SIZE/(4*16) - step;
348  offset = ff_fft_offsets_lut[n] << nbits;
349  tmpz = z + offset;
350 
351  tmp5 = tmpz[ n2].re + tmpz[n34].re;
352  tmp1 = tmpz[ n2].re - tmpz[n34].re;
353  tmp6 = tmpz[ n2].im + tmpz[n34].im;
354  tmp2 = tmpz[ n2].im - tmpz[n34].im;
355 
356  tmpz[ n2].re = tmpz[ 0].re - tmp5;
357  tmpz[ 0].re = tmpz[ 0].re + tmp5;
358  tmpz[ n2].im = tmpz[ 0].im - tmp6;
359  tmpz[ 0].im = tmpz[ 0].im + tmp6;
360  tmpz[n34].re = tmpz[n4].re - tmp2;
361  tmpz[ n4].re = tmpz[n4].re + tmp2;
362  tmpz[n34].im = tmpz[n4].im + tmp1;
363  tmpz[ n4].im = tmpz[n4].im - tmp1;
364 
365  for (i=1; i<n4; i++){
366  FFTSample w_re = w_re_ptr[0];
367  FFTSample w_im = w_im_ptr[0];
368  accu = (int64_t)w_re*tmpz[ n2+i].re;
369  accu += (int64_t)w_im*tmpz[ n2+i].im;
370  tmp1 = (int32_t)((accu + 0x40000000) >> 31);
371  accu = (int64_t)w_re*tmpz[ n2+i].im;
372  accu -= (int64_t)w_im*tmpz[ n2+i].re;
373  tmp2 = (int32_t)((accu + 0x40000000) >> 31);
374  accu = (int64_t)w_re*tmpz[n34+i].re;
375  accu -= (int64_t)w_im*tmpz[n34+i].im;
376  tmp3 = (int32_t)((accu + 0x40000000) >> 31);
377  accu = (int64_t)w_re*tmpz[n34+i].im;
378  accu += (int64_t)w_im*tmpz[n34+i].re;
379  tmp4 = (int32_t)((accu + 0x40000000) >> 31);
380 
381  tmp5 = tmp1 + tmp3;
382  tmp1 = tmp1 - tmp3;
383  tmp6 = tmp2 + tmp4;
384  tmp2 = tmp2 - tmp4;
385 
386  tmpz[ n2+i].re = tmpz[ i].re - tmp5;
387  tmpz[ i].re = tmpz[ i].re + tmp5;
388  tmpz[ n2+i].im = tmpz[ i].im - tmp6;
389  tmpz[ i].im = tmpz[ i].im + tmp6;
390  tmpz[n34+i].re = tmpz[n4+i].re - tmp2;
391  tmpz[ n4+i].re = tmpz[n4+i].re + tmp2;
392  tmpz[n34+i].im = tmpz[n4+i].im + tmp1;
393  tmpz[ n4+i].im = tmpz[n4+i].im - tmp1;
394 
395  w_re_ptr += step;
396  w_im_ptr -= step;
397  }
398  }
399  step >>= 1;
400  n4 <<= 1;
401  }
402 }
403 
404 #else /* FFT_FIXED_32 */
405 
406 #define BUTTERFLIES(a0,a1,a2,a3) {\
407  BF(t3, t5, t5, t1);\
408  BF(a2.re, a0.re, a0.re, t5);\
409  BF(a3.im, a1.im, a1.im, t3);\
410  BF(t4, t6, t2, t6);\
411  BF(a3.re, a1.re, a1.re, t4);\
412  BF(a2.im, a0.im, a0.im, t6);\
413 }
414 
415 // force loading all the inputs before storing any.
416 // this is slightly slower for small data, but avoids store->load aliasing
417 // for addresses separated by large powers of 2.
418 #define BUTTERFLIES_BIG(a0,a1,a2,a3) {\
419  FFTSample r0=a0.re, i0=a0.im, r1=a1.re, i1=a1.im;\
420  BF(t3, t5, t5, t1);\
421  BF(a2.re, a0.re, r0, t5);\
422  BF(a3.im, a1.im, i1, t3);\
423  BF(t4, t6, t2, t6);\
424  BF(a3.re, a1.re, r1, t4);\
425  BF(a2.im, a0.im, i0, t6);\
426 }
427 
428 #define TRANSFORM(a0,a1,a2,a3,wre,wim) {\
429  CMUL(t1, t2, a2.re, a2.im, wre, -wim);\
430  CMUL(t5, t6, a3.re, a3.im, wre, wim);\
431  BUTTERFLIES(a0,a1,a2,a3)\
432 }
433 
434 #define TRANSFORM_ZERO(a0,a1,a2,a3) {\
435  t1 = a2.re;\
436  t2 = a2.im;\
437  t5 = a3.re;\
438  t6 = a3.im;\
439  BUTTERFLIES(a0,a1,a2,a3)\
440 }
441 
442 /* z[0...8n-1], w[1...2n-1] */
443 #define PASS(name)\
444 static void name(FFTComplex *z, const FFTSample *wre, unsigned int n)\
445 {\
446  FFTDouble t1, t2, t3, t4, t5, t6;\
447  int o1 = 2*n;\
448  int o2 = 4*n;\
449  int o3 = 6*n;\
450  const FFTSample *wim = wre+o1;\
451  n--;\
452 \
453  TRANSFORM_ZERO(z[0],z[o1],z[o2],z[o3]);\
454  TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
455  do {\
456  z += 2;\
457  wre += 2;\
458  wim -= 2;\
459  TRANSFORM(z[0],z[o1],z[o2],z[o3],wre[0],wim[0]);\
460  TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
461  } while(--n);\
462 }
463 
464 PASS(pass)
465 #undef BUTTERFLIES
466 #define BUTTERFLIES BUTTERFLIES_BIG
467 PASS(pass_big)
468 
469 #define DECL_FFT(n,n2,n4)\
470 static void fft##n(FFTComplex *z)\
471 {\
472  fft##n2(z);\
473  fft##n4(z+n4*2);\
474  fft##n4(z+n4*3);\
475  pass(z,FFT_NAME(ff_cos_##n),n4/2);\
476 }
477 
478 static void fft4(FFTComplex *z)
479 {
480  FFTDouble t1, t2, t3, t4, t5, t6, t7, t8;
481 
482  BF(t3, t1, z[0].re, z[1].re);
483  BF(t8, t6, z[3].re, z[2].re);
484  BF(z[2].re, z[0].re, t1, t6);
485  BF(t4, t2, z[0].im, z[1].im);
486  BF(t7, t5, z[2].im, z[3].im);
487  BF(z[3].im, z[1].im, t4, t8);
488  BF(z[3].re, z[1].re, t3, t7);
489  BF(z[2].im, z[0].im, t2, t5);
490 }
491 
492 static void fft8(FFTComplex *z)
493 {
494  FFTDouble t1, t2, t3, t4, t5, t6;
495 
496  fft4(z);
497 
498  BF(t1, z[5].re, z[4].re, -z[5].re);
499  BF(t2, z[5].im, z[4].im, -z[5].im);
500  BF(t5, z[7].re, z[6].re, -z[7].re);
501  BF(t6, z[7].im, z[6].im, -z[7].im);
502 
503  BUTTERFLIES(z[0],z[2],z[4],z[6]);
504  TRANSFORM(z[1],z[3],z[5],z[7],sqrthalf,sqrthalf);
505 }
506 
507 #if !CONFIG_SMALL
508 static void fft16(FFTComplex *z)
509 {
510  FFTDouble t1, t2, t3, t4, t5, t6;
511  FFTSample cos_16_1 = FFT_NAME(ff_cos_16)[1];
512  FFTSample cos_16_3 = FFT_NAME(ff_cos_16)[3];
513 
514  fft8(z);
515  fft4(z+8);
516  fft4(z+12);
517 
518  TRANSFORM_ZERO(z[0],z[4],z[8],z[12]);
519  TRANSFORM(z[2],z[6],z[10],z[14],sqrthalf,sqrthalf);
520  TRANSFORM(z[1],z[5],z[9],z[13],cos_16_1,cos_16_3);
521  TRANSFORM(z[3],z[7],z[11],z[15],cos_16_3,cos_16_1);
522 }
523 #else
524 DECL_FFT(16,8,4)
525 #endif
526 DECL_FFT(32,16,8)
527 DECL_FFT(64,32,16)
528 DECL_FFT(128,64,32)
529 DECL_FFT(256,128,64)
530 DECL_FFT(512,256,128)
531 #if !CONFIG_SMALL
532 #define pass pass_big
533 #endif
534 DECL_FFT(1024,512,256)
535 DECL_FFT(2048,1024,512)
536 DECL_FFT(4096,2048,1024)
537 DECL_FFT(8192,4096,2048)
538 DECL_FFT(16384,8192,4096)
539 DECL_FFT(32768,16384,8192)
540 DECL_FFT(65536,32768,16384)
541 DECL_FFT(131072,65536,32768)
542 
543 static void (* const fft_dispatch[])(FFTComplex*) = {
544  fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512, fft1024,
545  fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072
546 };
547 
548 static void fft_calc_c(FFTContext *s, FFTComplex *z)
549 {
550  fft_dispatch[s->nbits-2](z);
551 }
552 #endif /* FFT_FIXED_32 */
static void fft_permute_c(FFTContext *s, FFTComplex *z)
Definition: fft_template.c:224
#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:466
float FFTDouble
Definition: fft.h:43
const char * s
Definition: avisynth_c.h:768
void(* mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:109
float re
Definition: fft.c:82
#define M_SQRT1_2
Definition: mathematics.h:58
static const int avx_tab[]
Definition: fft_template.c:104
void(* fft_permute)(struct FFTContext *s, FFTComplex *z)
Do the permutation needed BEFORE calling fft_calc().
Definition: fft.h:101
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:79
#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:152
const int32_t ff_w_tab_sr[MAX_FFT_SIZE/(4 *16)]
#define DECL_FFT(n, n2, n4)
Definition: fft_template.c:469
static void(*const fft_dispatch[])(FFTComplex *)
Definition: fft_template.c:543
#define FIX15(a)
Definition: fft-internal.h:62
#define t1
Definition: regdef.h:29
#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:89
static av_cold void fft_perm_avx(FFTContext *s)
Definition: fft_template.c:120
#define pass
Definition: fft_template.c:532
void(* imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:107
#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:142
uint32_t * revtab32
Definition: fft.h:113
#define PASS(name)
Definition: fft_template.c:443
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:108
void(* imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input)
Definition: fft.h:108
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
#define TRANSFORM(a0, a1, a2, a3, wre, wim)
Definition: fft_template.c:428
#define TRANSFORM_ZERO(a0, a1, a2, a3)
Definition: fft_template.c:434
static void fft4(FFTComplex *z)
Definition: fft_template.c:478
av_cold void ff_fft_end(FFTContext *s)
Definition: fft_template.c:239
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
static void fft8(FFTComplex *z)
Definition: fft_template.c:492
COSTABLE_CONST FFTSample *const FFT_NAME(ff_cos_tabs)[]
static const struct twinvq_data tab
#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:90
static void fft_calc_c(FFTContext *s, FFTComplex *z)
Definition: fft_template.c:548
static void fft16(FFTComplex *z)
Definition: fft_template.c:508
#define t2
Definition: regdef.h:30
definitions and tables for FFT
void(* mdct_calcw)(struct FFTContext *s, FFTDouble *output, const FFTSample *input)
Definition: fft.h:110
void ff_fft_init_x86(FFTContext *s)
Definition: fft_init.c:27
FFTComplex * tmp_buf
Definition: fft.h:92