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Diffstat (limited to 'Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_f64.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_f64.c | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_f64.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_f64.c new file mode 100644 index 0000000..d686eb8 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_f64.c @@ -0,0 +1,318 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_cfft_f64.c + * Description: Combined Radix Decimation in Frequency CFFT Double Precision Floating point processing function + * + * $Date: 23 April 2021 + * $Revision: V1.9.0 + * + * Target Processor: Cortex-M and Cortex-A cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved. + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the License); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an AS IS BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "dsp/transform_functions.h" +#include "arm_common_tables.h" + + +extern void arm_radix4_butterfly_f64( + float64_t * pSrc, + uint16_t fftLen, + const float64_t * pCoef, + uint16_t twidCoefModifier); + +extern void arm_bitreversal_64( + uint64_t * pSrc, + const uint16_t bitRevLen, + const uint16_t * pBitRevTable); + +/** +* @} end of ComplexFFT group +*/ + +/* ---------------------------------------------------------------------- + * Internal helper function used by the FFTs + * ---------------------------------------------------------------------- */ + +/* +* @brief Core function for the Double Precision floating-point CFFT butterfly process. +* @param[in, out] *pSrc points to the in-place buffer of F64 data type. +* @param[in] fftLen length of the FFT. +* @param[in] *pCoef points to the twiddle coefficient buffer. +* @param[in] twidCoefModifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table. +* @return none. +*/ + +void arm_radix4_butterfly_f64( + float64_t * pSrc, + uint16_t fftLen, + const float64_t * pCoef, + uint16_t twidCoefModifier) +{ + + float64_t co1, co2, co3, si1, si2, si3; + uint32_t ia1, ia2, ia3; + uint32_t i0, i1, i2, i3; + uint32_t n1, n2, j, k; + + float64_t t1, t2, r1, r2, s1, s2; + + + /* Initializations for the fft calculation */ + n2 = fftLen; + n1 = n2; + for (k = fftLen; k > 1U; k >>= 2U) + { + /* Initializations for the fft calculation */ + n1 = n2; + n2 >>= 2U; + ia1 = 0U; + + /* FFT Calculation */ + j = 0; + do + { + /* index calculation for the coefficients */ + ia2 = ia1 + ia1; + ia3 = ia2 + ia1; + co1 = pCoef[ia1 * 2U]; + si1 = pCoef[(ia1 * 2U) + 1U]; + co2 = pCoef[ia2 * 2U]; + si2 = pCoef[(ia2 * 2U) + 1U]; + co3 = pCoef[ia3 * 2U]; + si3 = pCoef[(ia3 * 2U) + 1U]; + + /* Twiddle coefficients index modifier */ + ia1 = ia1 + twidCoefModifier; + + i0 = j; + do + { + /* index calculation for the input as, */ + /* pSrc[i0 + 0], pSrc[i0 + fftLen/4], pSrc[i0 + fftLen/2], pSrc[i0 + 3fftLen/4] */ + i1 = i0 + n2; + i2 = i1 + n2; + i3 = i2 + n2; + + /* xa + xc */ + r1 = pSrc[(2U * i0)] + pSrc[(2U * i2)]; + + /* xa - xc */ + r2 = pSrc[(2U * i0)] - pSrc[(2U * i2)]; + + /* ya + yc */ + s1 = pSrc[(2U * i0) + 1U] + pSrc[(2U * i2) + 1U]; + + /* ya - yc */ + s2 = pSrc[(2U * i0) + 1U] - pSrc[(2U * i2) + 1U]; + + /* xb + xd */ + t1 = pSrc[2U * i1] + pSrc[2U * i3]; + + /* xa' = xa + xb + xc + xd */ + pSrc[2U * i0] = r1 + t1; + + /* xa + xc -(xb + xd) */ + r1 = r1 - t1; + + /* yb + yd */ + t2 = pSrc[(2U * i1) + 1U] + pSrc[(2U * i3) + 1U]; + + /* ya' = ya + yb + yc + yd */ + pSrc[(2U * i0) + 1U] = s1 + t2; + + /* (ya + yc) - (yb + yd) */ + s1 = s1 - t2; + + /* (yb - yd) */ + t1 = pSrc[(2U * i1) + 1U] - pSrc[(2U * i3) + 1U]; + + /* (xb - xd) */ + t2 = pSrc[2U * i1] - pSrc[2U * i3]; + + /* xc' = (xa-xb+xc-xd)co2 + (ya-yb+yc-yd)(si2) */ + pSrc[2U * i1] = (r1 * co2) + (s1 * si2); + + /* yc' = (ya-yb+yc-yd)co2 - (xa-xb+xc-xd)(si2) */ + pSrc[(2U * i1) + 1U] = (s1 * co2) - (r1 * si2); + + /* (xa - xc) + (yb - yd) */ + r1 = r2 + t1; + + /* (xa - xc) - (yb - yd) */ + r2 = r2 - t1; + + /* (ya - yc) - (xb - xd) */ + s1 = s2 - t2; + + /* (ya - yc) + (xb - xd) */ + s2 = s2 + t2; + + /* xb' = (xa+yb-xc-yd)co1 + (ya-xb-yc+xd)(si1) */ + pSrc[2U * i2] = (r1 * co1) + (s1 * si1); + + /* yb' = (ya-xb-yc+xd)co1 - (xa+yb-xc-yd)(si1) */ + pSrc[(2U * i2) + 1U] = (s1 * co1) - (r1 * si1); + + /* xd' = (xa-yb-xc+yd)co3 + (ya+xb-yc-xd)(si3) */ + pSrc[2U * i3] = (r2 * co3) + (s2 * si3); + + /* yd' = (ya+xb-yc-xd)co3 - (xa-yb-xc+yd)(si3) */ + pSrc[(2U * i3) + 1U] = (s2 * co3) - (r2 * si3); + + i0 += n1; + } while ( i0 < fftLen); + j++; + } while (j <= (n2 - 1U)); + twidCoefModifier <<= 2U; + } +} + +/* +* @brief Core function for the Double Precision floating-point CFFT butterfly process. +* @param[in, out] *pSrc points to the in-place buffer of F64 data type. +* @param[in] fftLen length of the FFT. +* @param[in] *pCoef points to the twiddle coefficient buffer. +* @param[in] twidCoefModifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table. +* @return none. +*/ + +void arm_cfft_radix4by2_f64( + float64_t * pSrc, + uint32_t fftLen, + const float64_t * pCoef) +{ + uint32_t i, l; + uint32_t n2, ia; + float64_t xt, yt, cosVal, sinVal; + float64_t p0, p1,p2,p3,a0,a1; + + n2 = fftLen >> 1; + ia = 0; + for (i = 0; i < n2; i++) + { + cosVal = pCoef[2*ia]; + sinVal = pCoef[2*ia + 1]; + ia++; + + l = i + n2; + + /* Butterfly implementation */ + a0 = pSrc[2 * i] + pSrc[2 * l]; + xt = pSrc[2 * i] - pSrc[2 * l]; + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + a1 = pSrc[2 * l + 1] + pSrc[2 * i + 1]; + + p0 = xt * cosVal; + p1 = yt * sinVal; + p2 = yt * cosVal; + p3 = xt * sinVal; + + pSrc[2 * i] = a0; + pSrc[2 * i + 1] = a1; + + pSrc[2 * l] = p0 + p1; + pSrc[2 * l + 1] = p2 - p3; + + } + + // first col + arm_radix4_butterfly_f64( pSrc, n2, (float64_t*)pCoef, 2U); + // second col + arm_radix4_butterfly_f64( pSrc + fftLen, n2, (float64_t*)pCoef, 2U); + +} + +/** + @addtogroup ComplexFFT + @{ + */ + +/** + @brief Processing function for the Double Precision floating-point complex FFT. + @param[in] S points to an instance of the Double Precision floating-point CFFT structure + @param[in,out] p1 points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place + @param[in] ifftFlag flag that selects transform direction + - value = 0: forward transform + - value = 1: inverse transform + @param[in] bitReverseFlag flag that enables / disables bit reversal of output + - value = 0: disables bit reversal of output + - value = 1: enables bit reversal of output + @return none + */ + +void arm_cfft_f64( + const arm_cfft_instance_f64 * S, + float64_t * p1, + uint8_t ifftFlag, + uint8_t bitReverseFlag) +{ + uint32_t L = S->fftLen, l; + float64_t invL, * pSrc; + + if (ifftFlag == 1U) + { + /* Conjugate input data */ + pSrc = p1 + 1; + for(l=0; l<L; l++) + { + *pSrc = -*pSrc; + pSrc += 2; + } + } + + switch (L) + { + case 16: + case 64: + case 256: + case 1024: + case 4096: + arm_radix4_butterfly_f64 (p1, L, (float64_t*)S->pTwiddle, 1U); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_f64 ( p1, L, (float64_t*)S->pTwiddle); + break; + + } + + if ( bitReverseFlag ) + arm_bitreversal_64((uint64_t*)p1, S->bitRevLength,S->pBitRevTable); + + if (ifftFlag == 1U) + { + invL = 1.0 / (float64_t)L; + /* Conjugate and scale output data */ + pSrc = p1; + for(l=0; l<L; l++) + { + *pSrc++ *= invL ; + *pSrc = -(*pSrc) * invL; + pSrc++; + } + } +} + +/** + @} end of ComplexFFT group + */ |