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25ade36 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 | #include "edge-impulse-sdk/dsp/config.hpp"
#if EIDSP_LOAD_CMSIS_DSP_SOURCES
/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_rfft_f32.c
* Description: RFFT & RIFFT Floating point process 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 "edge-impulse-sdk/CMSIS/DSP/Include/dsp/transform_functions.h"
/* ----------------------------------------------------------------------
* Internal functions prototypes
* -------------------------------------------------------------------- */
extern void arm_radix4_butterfly_f32(
float32_t * pSrc,
uint16_t fftLen,
const float32_t * pCoef,
uint16_t twidCoefModifier);
extern void arm_radix4_butterfly_inverse_f32(
float32_t * pSrc,
uint16_t fftLen,
const float32_t * pCoef,
uint16_t twidCoefModifier,
float32_t onebyfftLen);
extern void arm_bitreversal_f32(
float32_t * pSrc,
uint16_t fftSize,
uint16_t bitRevFactor,
const uint16_t * pBitRevTab);
void arm_split_rfft_f32(
float32_t * pSrc,
uint32_t fftLen,
const float32_t * pATable,
const float32_t * pBTable,
float32_t * pDst,
uint32_t modifier);
void arm_split_rifft_f32(
float32_t * pSrc,
uint32_t fftLen,
const float32_t * pATable,
const float32_t * pBTable,
float32_t * pDst,
uint32_t modifier);
/**
@ingroup groupTransforms
*/
/**
@addtogroup RealFFT
@{
*/
/**
@brief Processing function for the floating-point RFFT/RIFFT.
Source buffer is modified by this function.
@deprecated Do not use this function. It has been superceded by \ref arm_rfft_fast_f32 and will be removed in the future.
@param[in] S points to an instance of the floating-point RFFT/RIFFT structure
@param[in] pSrc points to the input buffer
@param[out] pDst points to the output buffer
@return none
@par
For the RIFFT, the source buffer must at least have length
fftLenReal + 2.
The last two elements must be equal to what would be generated
by the RFFT:
(pSrc[0] - pSrc[1]) and 0.0f
*/
void arm_rfft_f32(
const arm_rfft_instance_f32 * S,
float32_t * pSrc,
float32_t * pDst)
{
const arm_cfft_radix4_instance_f32 *S_CFFT = S->pCfft;
/* Calculation of Real IFFT of input */
if (S->ifftFlagR == 1U)
{
/* Real IFFT core process */
arm_split_rifft_f32 (pSrc, S->fftLenBy2, S->pTwiddleAReal, S->pTwiddleBReal, pDst, S->twidCoefRModifier);
/* Complex radix-4 IFFT process */
arm_radix4_butterfly_inverse_f32 (pDst, S_CFFT->fftLen, S_CFFT->pTwiddle, S_CFFT->twidCoefModifier, S_CFFT->onebyfftLen);
/* Bit reversal process */
if (S->bitReverseFlagR == 1U)
{
arm_bitreversal_f32 (pDst, S_CFFT->fftLen, S_CFFT->bitRevFactor, S_CFFT->pBitRevTable);
}
}
else
{
/* Calculation of RFFT of input */
/* Complex radix-4 FFT process */
arm_radix4_butterfly_f32 (pSrc, S_CFFT->fftLen, S_CFFT->pTwiddle, S_CFFT->twidCoefModifier);
/* Bit reversal process */
if (S->bitReverseFlagR == 1U)
{
arm_bitreversal_f32 (pSrc, S_CFFT->fftLen, S_CFFT->bitRevFactor, S_CFFT->pBitRevTable);
}
/* Real FFT core process */
arm_split_rfft_f32 (pSrc, S->fftLenBy2, S->pTwiddleAReal, S->pTwiddleBReal, pDst, S->twidCoefRModifier);
}
}
/**
@} end of RealFFT group
*/
/**
@brief Core Real FFT process
@param[in] pSrc points to input buffer
@param[in] fftLen length of FFT
@param[in] pATable points to twiddle Coef A buffer
@param[in] pBTable points to twiddle Coef B buffer
@param[out] pDst points to output buffer
@param[in] modifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table
@return none
*/
void arm_split_rfft_f32(
float32_t * pSrc,
uint32_t fftLen,
const float32_t * pATable,
const float32_t * pBTable,
float32_t * pDst,
uint32_t modifier)
{
uint32_t i; /* Loop Counter */
float32_t outR, outI; /* Temporary variables for output */
const float32_t *pCoefA, *pCoefB; /* Temporary pointers for twiddle factors */
float32_t CoefA1, CoefA2, CoefB1; /* Temporary variables for twiddle coefficients */
float32_t *pDst1 = &pDst[2], *pDst2 = &pDst[(4U * fftLen) - 1U]; /* temp pointers for output buffer */
float32_t *pSrc1 = &pSrc[2], *pSrc2 = &pSrc[(2U * fftLen) - 1U]; /* temp pointers for input buffer */
/* Init coefficient pointers */
pCoefA = &pATable[modifier * 2];
pCoefB = &pBTable[modifier * 2];
i = fftLen - 1U;
while (i > 0U)
{
/*
outR = ( pSrc[2 * i] * pATable[2 * i]
- pSrc[2 * i + 1] * pATable[2 * i + 1]
+ pSrc[2 * n - 2 * i] * pBTable[2 * i]
+ pSrc[2 * n - 2 * i + 1] * pBTable[2 * i + 1]);
outI = ( pIn[2 * i + 1] * pATable[2 * i]
+ pIn[2 * i] * pATable[2 * i + 1]
+ pIn[2 * n - 2 * i] * pBTable[2 * i + 1]
- pIn[2 * n - 2 * i + 1] * pBTable[2 * i]);
*/
/* read pATable[2 * i] */
CoefA1 = *pCoefA++;
/* pATable[2 * i + 1] */
CoefA2 = *pCoefA;
/* pSrc[2 * i] * pATable[2 * i] */
outR = *pSrc1 * CoefA1;
/* pSrc[2 * i] * CoefA2 */
outI = *pSrc1++ * CoefA2;
/* (pSrc[2 * i + 1] + pSrc[2 * fftLen - 2 * i + 1]) * CoefA2 */
outR -= (*pSrc1 + *pSrc2) * CoefA2;
/* pSrc[2 * i + 1] * CoefA1 */
outI += *pSrc1++ * CoefA1;
CoefB1 = *pCoefB;
/* pSrc[2 * fftLen - 2 * i + 1] * CoefB1 */
outI -= *pSrc2-- * CoefB1;
/* pSrc[2 * fftLen - 2 * i] * CoefA2 */
outI -= *pSrc2 * CoefA2;
/* pSrc[2 * fftLen - 2 * i] * CoefB1 */
outR += *pSrc2-- * CoefB1;
/* write output */
*pDst1++ = outR;
*pDst1++ = outI;
/* write complex conjugate output */
*pDst2-- = -outI;
*pDst2-- = outR;
/* update coefficient pointer */
pCoefB = pCoefB + (modifier * 2U);
pCoefA = pCoefA + ((modifier * 2U) - 1U);
i--;
}
pDst[2U * fftLen] = pSrc[0] - pSrc[1];
pDst[(2U * fftLen) + 1U] = 0.0f;
pDst[0] = pSrc[0] + pSrc[1];
pDst[1] = 0.0f;
}
/**
@brief Core Real IFFT process
@param[in] pSrc points to input buffer
@param[in] fftLen length of FFT
@param[in] pATable points to twiddle Coef A buffer
@param[in] pBTable points to twiddle Coef B buffer
@param[out] pDst points to output buffer
@param[in] modifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table
@return none
*/
void arm_split_rifft_f32(
float32_t * pSrc,
uint32_t fftLen,
const float32_t * pATable,
const float32_t * pBTable,
float32_t * pDst,
uint32_t modifier)
{
float32_t outR, outI; /* Temporary variables for output */
const float32_t *pCoefA, *pCoefB; /* Temporary pointers for twiddle factors */
float32_t CoefA1, CoefA2, CoefB1; /* Temporary variables for twiddle coefficients */
float32_t *pSrc1 = &pSrc[0], *pSrc2 = &pSrc[(2U * fftLen) + 1U];
pCoefA = &pATable[0];
pCoefB = &pBTable[0];
while (fftLen > 0U)
{
/*
outR = ( pIn[2 * i] * pATable[2 * i]
+ pIn[2 * i + 1] * pATable[2 * i + 1]
+ pIn[2 * n - 2 * i] * pBTable[2 * i]
- pIn[2 * n - 2 * i + 1] * pBTable[2 * i + 1]);
outI = ( pIn[2 * i + 1] * pATable[2 * i]
- pIn[2 * i] * pATable[2 * i + 1]
- pIn[2 * n - 2 * i] * pBTable[2 * i + 1]
- pIn[2 * n - 2 * i + 1] * pBTable[2 * i]);
*/
CoefA1 = *pCoefA++;
CoefA2 = *pCoefA;
/* outR = (pSrc[2 * i] * CoefA1 */
outR = *pSrc1 * CoefA1;
/* - pSrc[2 * i] * CoefA2 */
outI = -(*pSrc1++) * CoefA2;
/* (pSrc[2 * i + 1] + pSrc[2 * fftLen - 2 * i + 1]) * CoefA2 */
outR += (*pSrc1 + *pSrc2) * CoefA2;
/* pSrc[2 * i + 1] * CoefA1 */
outI += (*pSrc1++) * CoefA1;
CoefB1 = *pCoefB;
/* - pSrc[2 * fftLen - 2 * i + 1] * CoefB1 */
outI -= *pSrc2-- * CoefB1;
/* pSrc[2 * fftLen - 2 * i] * CoefB1 */
outR += *pSrc2 * CoefB1;
/* pSrc[2 * fftLen - 2 * i] * CoefA2 */
outI += *pSrc2-- * CoefA2;
/* write output */
*pDst++ = outR;
*pDst++ = outI;
/* update coefficient pointer */
pCoefB = pCoefB + (modifier * 2);
pCoefA = pCoefA + (modifier * 2 - 1);
/* Decrement loop count */
fftLen--;
}
}
#endif // EIDSP_LOAD_CMSIS_DSP_SOURCES
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