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arm_cfft_radix2_q15.c
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1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
3 *
4 * $Date: 19. March 2015
5 * $Revision: V.1.4.5
6 *
7 * Project: CMSIS DSP Library
8 * Title: arm_cfft_radix2_q15.c
9 *
10 * Description: Radix-2 Decimation in Frequency CFFT & CIFFT Fixed point processing function
11 *
12 *
13 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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41 
42 #include "arm_math.h"
43 
44 void arm_radix2_butterfly_q15(
45  q15_t * pSrc,
46  uint32_t fftLen,
47  q15_t * pCoef,
48  uint16_t twidCoefModifier);
49 
50 void arm_radix2_butterfly_inverse_q15(
51  q15_t * pSrc,
52  uint32_t fftLen,
53  q15_t * pCoef,
54  uint16_t twidCoefModifier);
55 
56 void arm_bitreversal_q15(
57  q15_t * pSrc,
58  uint32_t fftLen,
59  uint16_t bitRevFactor,
60  uint16_t * pBitRevTab);
61 
80 void arm_cfft_radix2_q15(
81  const arm_cfft_radix2_instance_q15 * S,
82  q15_t * pSrc)
83 {
84 
85  if(S->ifftFlag == 1u)
86  {
87  arm_radix2_butterfly_inverse_q15(pSrc, S->fftLen,
88  S->pTwiddle, S->twidCoefModifier);
89  }
90  else
91  {
92  arm_radix2_butterfly_q15(pSrc, S->fftLen,
93  S->pTwiddle, S->twidCoefModifier);
94  }
95 
96  arm_bitreversal_q15(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
97 }
98 
103 void arm_radix2_butterfly_q15(
104  q15_t * pSrc,
105  uint32_t fftLen,
106  q15_t * pCoef,
107  uint16_t twidCoefModifier)
108 {
109 #ifndef ARM_MATH_CM0_FAMILY
110 
111  unsigned i, j, k, l;
112  unsigned n1, n2, ia;
113  q15_t in;
114  q31_t T, S, R;
115  q31_t coeff, out1, out2;
116 
117  //N = fftLen;
118  n2 = fftLen;
119 
120  n1 = n2;
121  n2 = n2 >> 1;
122  ia = 0;
123 
124  // loop for groups
125  for (i = 0; i < n2; i++)
126  {
127  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
128 
129  ia = ia + twidCoefModifier;
130 
131  l = i + n2;
132 
133  T = _SIMD32_OFFSET(pSrc + (2 * i));
134  in = ((int16_t) (T & 0xFFFF)) >> 1;
135  T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
136 
137  S = _SIMD32_OFFSET(pSrc + (2 * l));
138  in = ((int16_t) (S & 0xFFFF)) >> 1;
139  S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
140 
141  R = __QSUB16(T, S);
142 
143  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
144 
145 #ifndef ARM_MATH_BIG_ENDIAN
146 
147  out1 = __SMUAD(coeff, R) >> 16;
148  out2 = __SMUSDX(coeff, R);
149 
150 #else
151 
152  out1 = __SMUSDX(R, coeff) >> 16u;
153  out2 = __SMUAD(coeff, R);
154 
155 #endif // #ifndef ARM_MATH_BIG_ENDIAN
156 
157  _SIMD32_OFFSET(pSrc + (2u * l)) =
158  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
159 
160  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
161 
162  ia = ia + twidCoefModifier;
163 
164  // loop for butterfly
165  i++;
166  l++;
167 
168  T = _SIMD32_OFFSET(pSrc + (2 * i));
169  in = ((int16_t) (T & 0xFFFF)) >> 1;
170  T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
171 
172  S = _SIMD32_OFFSET(pSrc + (2 * l));
173  in = ((int16_t) (S & 0xFFFF)) >> 1;
174  S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
175 
176  R = __QSUB16(T, S);
177 
178  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
179 
180 #ifndef ARM_MATH_BIG_ENDIAN
181 
182  out1 = __SMUAD(coeff, R) >> 16;
183  out2 = __SMUSDX(coeff, R);
184 
185 #else
186 
187  out1 = __SMUSDX(R, coeff) >> 16u;
188  out2 = __SMUAD(coeff, R);
189 
190 #endif // #ifndef ARM_MATH_BIG_ENDIAN
191 
192  _SIMD32_OFFSET(pSrc + (2u * l)) =
193  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
194 
195  } // groups loop end
196 
197  twidCoefModifier = twidCoefModifier << 1u;
198 
199  // loop for stage
200  for (k = fftLen / 2; k > 2; k = k >> 1)
201  {
202  n1 = n2;
203  n2 = n2 >> 1;
204  ia = 0;
205 
206  // loop for groups
207  for (j = 0; j < n2; j++)
208  {
209  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
210 
211  ia = ia + twidCoefModifier;
212 
213  // loop for butterfly
214  for (i = j; i < fftLen; i += n1)
215  {
216  l = i + n2;
217 
218  T = _SIMD32_OFFSET(pSrc + (2 * i));
219 
220  S = _SIMD32_OFFSET(pSrc + (2 * l));
221 
222  R = __QSUB16(T, S);
223 
224  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
225 
226 #ifndef ARM_MATH_BIG_ENDIAN
227 
228  out1 = __SMUAD(coeff, R) >> 16;
229  out2 = __SMUSDX(coeff, R);
230 
231 #else
232 
233  out1 = __SMUSDX(R, coeff) >> 16u;
234  out2 = __SMUAD(coeff, R);
235 
236 #endif // #ifndef ARM_MATH_BIG_ENDIAN
237 
238  _SIMD32_OFFSET(pSrc + (2u * l)) =
239  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
240 
241  i += n1;
242 
243  l = i + n2;
244 
245  T = _SIMD32_OFFSET(pSrc + (2 * i));
246 
247  S = _SIMD32_OFFSET(pSrc + (2 * l));
248 
249  R = __QSUB16(T, S);
250 
251  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
252 
253 #ifndef ARM_MATH_BIG_ENDIAN
254 
255  out1 = __SMUAD(coeff, R) >> 16;
256  out2 = __SMUSDX(coeff, R);
257 
258 #else
259 
260  out1 = __SMUSDX(R, coeff) >> 16u;
261  out2 = __SMUAD(coeff, R);
262 
263 #endif // #ifndef ARM_MATH_BIG_ENDIAN
264 
265  _SIMD32_OFFSET(pSrc + (2u * l)) =
266  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
267 
268  } // butterfly loop end
269 
270  } // groups loop end
271 
272  twidCoefModifier = twidCoefModifier << 1u;
273  } // stages loop end
274 
275  n1 = n2;
276  n2 = n2 >> 1;
277  ia = 0;
278 
279  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
280 
281  ia = ia + twidCoefModifier;
282 
283  // loop for butterfly
284  for (i = 0; i < fftLen; i += n1)
285  {
286  l = i + n2;
287 
288  T = _SIMD32_OFFSET(pSrc + (2 * i));
289 
290  S = _SIMD32_OFFSET(pSrc + (2 * l));
291 
292  R = __QSUB16(T, S);
293 
294  _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
295 
296  _SIMD32_OFFSET(pSrc + (2u * l)) = R;
297 
298  i += n1;
299  l = i + n2;
300 
301  T = _SIMD32_OFFSET(pSrc + (2 * i));
302 
303  S = _SIMD32_OFFSET(pSrc + (2 * l));
304 
305  R = __QSUB16(T, S);
306 
307  _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
308 
309  _SIMD32_OFFSET(pSrc + (2u * l)) = R;
310 
311  } // groups loop end
312 
313 
314 #else
315 
316  unsigned i, j, k, l;
317  unsigned n1, n2, ia;
318  q15_t xt, yt, cosVal, sinVal;
319 
320 
321  //N = fftLen;
322  n2 = fftLen;
323 
324  n1 = n2;
325  n2 = n2 >> 1;
326  ia = 0;
327 
328  // loop for groups
329  for (j = 0; j < n2; j++)
330  {
331  cosVal = pCoef[ia * 2];
332  sinVal = pCoef[(ia * 2) + 1];
333  ia = ia + twidCoefModifier;
334 
335  // loop for butterfly
336  for (i = j; i < fftLen; i += n1)
337  {
338  l = i + n2;
339  xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u);
340  pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u;
341 
342  yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u);
343  pSrc[2 * i + 1] =
344  ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u;
345 
346  pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
347  ((int16_t) (((q31_t) yt * sinVal) >> 16)));
348 
349  pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
350  ((int16_t) (((q31_t) xt * sinVal) >> 16)));
351 
352  } // butterfly loop end
353 
354  } // groups loop end
355 
356  twidCoefModifier = twidCoefModifier << 1u;
357 
358  // loop for stage
359  for (k = fftLen / 2; k > 2; k = k >> 1)
360  {
361  n1 = n2;
362  n2 = n2 >> 1;
363  ia = 0;
364 
365  // loop for groups
366  for (j = 0; j < n2; j++)
367  {
368  cosVal = pCoef[ia * 2];
369  sinVal = pCoef[(ia * 2) + 1];
370  ia = ia + twidCoefModifier;
371 
372  // loop for butterfly
373  for (i = j; i < fftLen; i += n1)
374  {
375  l = i + n2;
376  xt = pSrc[2 * i] - pSrc[2 * l];
377  pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
378 
379  yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
380  pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
381 
382  pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
383  ((int16_t) (((q31_t) yt * sinVal) >> 16)));
384 
385  pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
386  ((int16_t) (((q31_t) xt * sinVal) >> 16)));
387 
388  } // butterfly loop end
389 
390  } // groups loop end
391 
392  twidCoefModifier = twidCoefModifier << 1u;
393  } // stages loop end
394 
395  n1 = n2;
396  n2 = n2 >> 1;
397  ia = 0;
398 
399  // loop for groups
400  for (j = 0; j < n2; j++)
401  {
402  cosVal = pCoef[ia * 2];
403  sinVal = pCoef[(ia * 2) + 1];
404 
405  ia = ia + twidCoefModifier;
406 
407  // loop for butterfly
408  for (i = j; i < fftLen; i += n1)
409  {
410  l = i + n2;
411  xt = pSrc[2 * i] - pSrc[2 * l];
412  pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
413 
414  yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
415  pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
416 
417  pSrc[2u * l] = xt;
418 
419  pSrc[2u * l + 1u] = yt;
420 
421  } // butterfly loop end
422 
423  } // groups loop end
424 
425  twidCoefModifier = twidCoefModifier << 1u;
426 
427 #endif // #ifndef ARM_MATH_CM0_FAMILY
428 
429 }
430 
431 
432 void arm_radix2_butterfly_inverse_q15(
433  q15_t * pSrc,
434  uint32_t fftLen,
435  q15_t * pCoef,
436  uint16_t twidCoefModifier)
437 {
438 #ifndef ARM_MATH_CM0_FAMILY
439 
440  unsigned i, j, k, l;
441  unsigned n1, n2, ia;
442  q15_t in;
443  q31_t T, S, R;
444  q31_t coeff, out1, out2;
445 
446  //N = fftLen;
447  n2 = fftLen;
448 
449  n1 = n2;
450  n2 = n2 >> 1;
451  ia = 0;
452 
453  // loop for groups
454  for (i = 0; i < n2; i++)
455  {
456  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
457 
458  ia = ia + twidCoefModifier;
459 
460  l = i + n2;
461 
462  T = _SIMD32_OFFSET(pSrc + (2 * i));
463  in = ((int16_t) (T & 0xFFFF)) >> 1;
464  T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
465 
466  S = _SIMD32_OFFSET(pSrc + (2 * l));
467  in = ((int16_t) (S & 0xFFFF)) >> 1;
468  S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
469 
470  R = __QSUB16(T, S);
471 
472  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
473 
474 #ifndef ARM_MATH_BIG_ENDIAN
475 
476  out1 = __SMUSD(coeff, R) >> 16;
477  out2 = __SMUADX(coeff, R);
478 #else
479 
480  out1 = __SMUADX(R, coeff) >> 16u;
481  out2 = __SMUSD(__QSUB(0, coeff), R);
482 
483 #endif // #ifndef ARM_MATH_BIG_ENDIAN
484 
485  _SIMD32_OFFSET(pSrc + (2u * l)) =
486  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
487 
488  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
489 
490  ia = ia + twidCoefModifier;
491 
492  // loop for butterfly
493  i++;
494  l++;
495 
496  T = _SIMD32_OFFSET(pSrc + (2 * i));
497  in = ((int16_t) (T & 0xFFFF)) >> 1;
498  T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
499 
500  S = _SIMD32_OFFSET(pSrc + (2 * l));
501  in = ((int16_t) (S & 0xFFFF)) >> 1;
502  S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
503 
504  R = __QSUB16(T, S);
505 
506  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
507 
508 #ifndef ARM_MATH_BIG_ENDIAN
509 
510  out1 = __SMUSD(coeff, R) >> 16;
511  out2 = __SMUADX(coeff, R);
512 #else
513 
514  out1 = __SMUADX(R, coeff) >> 16u;
515  out2 = __SMUSD(__QSUB(0, coeff), R);
516 
517 #endif // #ifndef ARM_MATH_BIG_ENDIAN
518 
519  _SIMD32_OFFSET(pSrc + (2u * l)) =
520  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
521 
522  } // groups loop end
523 
524  twidCoefModifier = twidCoefModifier << 1u;
525 
526  // loop for stage
527  for (k = fftLen / 2; k > 2; k = k >> 1)
528  {
529  n1 = n2;
530  n2 = n2 >> 1;
531  ia = 0;
532 
533  // loop for groups
534  for (j = 0; j < n2; j++)
535  {
536  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
537 
538  ia = ia + twidCoefModifier;
539 
540  // loop for butterfly
541  for (i = j; i < fftLen; i += n1)
542  {
543  l = i + n2;
544 
545  T = _SIMD32_OFFSET(pSrc + (2 * i));
546 
547  S = _SIMD32_OFFSET(pSrc + (2 * l));
548 
549  R = __QSUB16(T, S);
550 
551  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
552 
553 #ifndef ARM_MATH_BIG_ENDIAN
554 
555  out1 = __SMUSD(coeff, R) >> 16;
556  out2 = __SMUADX(coeff, R);
557 
558 #else
559 
560  out1 = __SMUADX(R, coeff) >> 16u;
561  out2 = __SMUSD(__QSUB(0, coeff), R);
562 
563 #endif // #ifndef ARM_MATH_BIG_ENDIAN
564 
565  _SIMD32_OFFSET(pSrc + (2u * l)) =
566  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
567 
568  i += n1;
569 
570  l = i + n2;
571 
572  T = _SIMD32_OFFSET(pSrc + (2 * i));
573 
574  S = _SIMD32_OFFSET(pSrc + (2 * l));
575 
576  R = __QSUB16(T, S);
577 
578  _SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
579 
580 #ifndef ARM_MATH_BIG_ENDIAN
581 
582  out1 = __SMUSD(coeff, R) >> 16;
583  out2 = __SMUADX(coeff, R);
584 #else
585 
586  out1 = __SMUADX(R, coeff) >> 16u;
587  out2 = __SMUSD(__QSUB(0, coeff), R);
588 
589 #endif // #ifndef ARM_MATH_BIG_ENDIAN
590 
591  _SIMD32_OFFSET(pSrc + (2u * l)) =
592  (q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
593 
594  } // butterfly loop end
595 
596  } // groups loop end
597 
598  twidCoefModifier = twidCoefModifier << 1u;
599  } // stages loop end
600 
601  n1 = n2;
602  n2 = n2 >> 1;
603  ia = 0;
604 
605  // loop for groups
606  for (j = 0; j < n2; j++)
607  {
608  coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
609 
610  ia = ia + twidCoefModifier;
611 
612  // loop for butterfly
613  for (i = j; i < fftLen; i += n1)
614  {
615  l = i + n2;
616 
617  T = _SIMD32_OFFSET(pSrc + (2 * i));
618 
619  S = _SIMD32_OFFSET(pSrc + (2 * l));
620 
621  R = __QSUB16(T, S);
622 
623  _SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
624 
625  _SIMD32_OFFSET(pSrc + (2u * l)) = R;
626 
627  } // butterfly loop end
628 
629  } // groups loop end
630 
631  twidCoefModifier = twidCoefModifier << 1u;
632 
633 #else
634 
635 
636  unsigned i, j, k, l;
637  unsigned n1, n2, ia;
638  q15_t xt, yt, cosVal, sinVal;
639 
640  //N = fftLen;
641  n2 = fftLen;
642 
643  n1 = n2;
644  n2 = n2 >> 1;
645  ia = 0;
646 
647  // loop for groups
648  for (j = 0; j < n2; j++)
649  {
650  cosVal = pCoef[ia * 2];
651  sinVal = pCoef[(ia * 2) + 1];
652  ia = ia + twidCoefModifier;
653 
654  // loop for butterfly
655  for (i = j; i < fftLen; i += n1)
656  {
657  l = i + n2;
658  xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u);
659  pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u;
660 
661  yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u);
662  pSrc[2 * i + 1] =
663  ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u;
664 
665  pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
666  ((int16_t) (((q31_t) yt * sinVal) >> 16)));
667 
668  pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
669  ((int16_t) (((q31_t) xt * sinVal) >> 16)));
670 
671  } // butterfly loop end
672 
673  } // groups loop end
674 
675  twidCoefModifier = twidCoefModifier << 1u;
676 
677  // loop for stage
678  for (k = fftLen / 2; k > 2; k = k >> 1)
679  {
680  n1 = n2;
681  n2 = n2 >> 1;
682  ia = 0;
683 
684  // loop for groups
685  for (j = 0; j < n2; j++)
686  {
687  cosVal = pCoef[ia * 2];
688  sinVal = pCoef[(ia * 2) + 1];
689  ia = ia + twidCoefModifier;
690 
691  // loop for butterfly
692  for (i = j; i < fftLen; i += n1)
693  {
694  l = i + n2;
695  xt = pSrc[2 * i] - pSrc[2 * l];
696  pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
697 
698  yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
699  pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
700 
701  pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
702  ((int16_t) (((q31_t) yt * sinVal) >> 16)));
703 
704  pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
705  ((int16_t) (((q31_t) xt * sinVal) >> 16)));
706 
707  } // butterfly loop end
708 
709  } // groups loop end
710 
711  twidCoefModifier = twidCoefModifier << 1u;
712  } // stages loop end
713 
714  n1 = n2;
715  n2 = n2 >> 1;
716  ia = 0;
717 
718  cosVal = pCoef[ia * 2];
719  sinVal = pCoef[(ia * 2) + 1];
720 
721  ia = ia + twidCoefModifier;
722 
723  // loop for butterfly
724  for (i = 0; i < fftLen; i += n1)
725  {
726  l = i + n2;
727  xt = pSrc[2 * i] - pSrc[2 * l];
728  pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
729 
730  yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
731  pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
732 
733  pSrc[2u * l] = xt;
734 
735  pSrc[2u * l + 1u] = yt;
736 
737  } // groups loop end
738 
739 
740 #endif // #ifndef ARM_MATH_CM0_FAMILY
741 
742 }
arm_cfft_radix2_instance_q15::bitRevFactor
uint16_t bitRevFactor
Definition: arm_math.h:1956
arm_radix2_butterfly_q15
void arm_radix2_butterfly_q15(q15_t *pSrc, uint32_t fftLen, q15_t *pCoef, uint16_t twidCoefModifier)
Definition: arm_cfft_radix2_q15.c:103
arm_math.h
arm_cfft_radix2_q15
void arm_cfft_radix2_q15(const arm_cfft_radix2_instance_q15 *S, q15_t *pSrc)
Processing function for the fixed-point CFFT/CIFFT.
Definition: arm_cfft_radix2_q15.c:80
arm_cfft_radix2_instance_q15::pBitRevTable
uint16_t * pBitRevTable
Definition: arm_math.h:1954
arm_bitreversal_q15
void arm_bitreversal_q15(q15_t *pSrc, uint32_t fftLen, uint16_t bitRevFactor, uint16_t *pBitRevTab)
Definition: arm_bitreversal.c:196
arm_radix2_butterfly_inverse_q15
void arm_radix2_butterfly_inverse_q15(q15_t *pSrc, uint32_t fftLen, q15_t *pCoef, uint16_t twidCoefModifier)
Definition: arm_cfft_radix2_q15.c:432
q15_t
int16_t q15_t
16-bit fractional data type in 1.15 format.
Definition: arm_math.h:392
arm_cfft_radix2_instance_q15::twidCoefModifier
uint16_t twidCoefModifier
Definition: arm_math.h:1955
_SIMD32_OFFSET
#define _SIMD32_OFFSET(addr)
Definition: arm_math.h:447
q31_t
int32_t q31_t
32-bit fractional data type in 1.31 format.
Definition: arm_math.h:397
arm_cfft_radix2_instance_q15::fftLen
uint16_t fftLen
Definition: arm_math.h:1950
arm_cfft_radix2_instance_q15::pTwiddle
q15_t * pTwiddle
Definition: arm_math.h:1953
arm_cfft_radix2_instance_q15
Instance structure for the Q15 CFFT/CIFFT function.
Definition: arm_math.h:1948
arm_cfft_radix2_instance_q15::ifftFlag
uint8_t ifftFlag
Definition: arm_math.h:1951
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