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Diffstat (limited to 'DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c')
-rw-r--r-- | DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c b/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c new file mode 100644 index 0000000..6ed9a80 --- /dev/null +++ b/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c @@ -0,0 +1,351 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2014 ARM Limited. All rights reserved. +* +* $Date: 19. March 2015 +* $Revision: V.1.4.5 +* +* Project: CMSIS DSP Library +* Title: arm_cfft_radix2_q31.c +* +* Description: Radix-2 Decimation in Frequency CFFT & CIFFT Fixed point processing function +* +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions +* are met: +* - Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* - Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in +* the documentation and/or other materials provided with the +* distribution. +* - Neither the name of ARM LIMITED nor the names of its contributors +* may be used to endorse or promote products derived from this +* software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +* POSSIBILITY OF SUCH DAMAGE. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +void arm_radix2_butterfly_q31( + q31_t * pSrc, + uint32_t fftLen, + q31_t * pCoef, + uint16_t twidCoefModifier); + +void arm_radix2_butterfly_inverse_q31( + q31_t * pSrc, + uint32_t fftLen, + q31_t * pCoef, + uint16_t twidCoefModifier); + +void arm_bitreversal_q31( + q31_t * pSrc, + uint32_t fftLen, + uint16_t bitRevFactor, + uint16_t * pBitRevTab); + +/** +* @ingroup groupTransforms +*/ + +/** +* @addtogroup ComplexFFT +* @{ +*/ + +/** +* @details +* @brief Processing function for the fixed-point CFFT/CIFFT. +* @deprecated Do not use this function. It has been superseded by \ref arm_cfft_q31 and will be removed +* @param[in] *S points to an instance of the fixed-point CFFT/CIFFT structure. +* @param[in, out] *pSrc points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place. +* @return none. +*/ + +void arm_cfft_radix2_q31( +const arm_cfft_radix2_instance_q31 * S, +q31_t * pSrc) +{ + + if(S->ifftFlag == 1u) + { + arm_radix2_butterfly_inverse_q31(pSrc, S->fftLen, + S->pTwiddle, S->twidCoefModifier); + } + else + { + arm_radix2_butterfly_q31(pSrc, S->fftLen, + S->pTwiddle, S->twidCoefModifier); + } + + arm_bitreversal_q31(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable); +} + +/** +* @} end of ComplexFFT group +*/ + +void arm_radix2_butterfly_q31( +q31_t * pSrc, +uint32_t fftLen, +q31_t * pCoef, +uint16_t twidCoefModifier) +{ + + unsigned i, j, k, l, m; + unsigned n1, n2, ia; + q31_t xt, yt, cosVal, sinVal; + q31_t p0, p1; + + //N = fftLen; + n2 = fftLen; + + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + // loop for groups + for (i = 0; i < n2; i++) + { + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + l = i + n2; + xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u); + pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u; + + yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u); + pSrc[2 * i + 1] = + ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u; + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multAcc_32x32_keep32_R(p0, yt, sinVal); + multSub_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2u * l] = p0; + pSrc[2u * l + 1u] = p1; + + } // groups loop end + + twidCoefModifier <<= 1u; + + // loop for stage + for (k = fftLen / 2; k > 2; k = k >> 1) + { + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + // loop for groups + for (j = 0; j < n2; j++) + { + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + // loop for butterfly + i = j; + m = fftLen / n1; + do + { + l = i + n2; + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u; + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u; + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multAcc_32x32_keep32_R(p0, yt, sinVal); + multSub_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2u * l] = p0; + pSrc[2u * l + 1u] = p1; + i += n1; + m--; + } while( m > 0); // butterfly loop end + + } // groups loop end + + twidCoefModifier <<= 1u; + } // stages loop end + + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + // loop for butterfly + for (i = 0; i < fftLen; i += n1) + { + l = i + n2; + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]); + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]); + + pSrc[2u * l] = xt; + + pSrc[2u * l + 1u] = yt; + + i += n1; + l = i + n2; + + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]); + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]); + + pSrc[2u * l] = xt; + + pSrc[2u * l + 1u] = yt; + + } // butterfly loop end + +} + + +void arm_radix2_butterfly_inverse_q31( +q31_t * pSrc, +uint32_t fftLen, +q31_t * pCoef, +uint16_t twidCoefModifier) +{ + + unsigned i, j, k, l; + unsigned n1, n2, ia; + q31_t xt, yt, cosVal, sinVal; + q31_t p0, p1; + + //N = fftLen; + n2 = fftLen; + + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + // loop for groups + for (i = 0; i < n2; i++) + { + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + l = i + n2; + xt = (pSrc[2 * i] >> 1u) - (pSrc[2 * l] >> 1u); + pSrc[2 * i] = ((pSrc[2 * i] >> 1u) + (pSrc[2 * l] >> 1u)) >> 1u; + + yt = (pSrc[2 * i + 1] >> 1u) - (pSrc[2 * l + 1] >> 1u); + pSrc[2 * i + 1] = + ((pSrc[2 * l + 1] >> 1u) + (pSrc[2 * i + 1] >> 1u)) >> 1u; + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multSub_32x32_keep32_R(p0, yt, sinVal); + multAcc_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2u * l] = p0; + pSrc[2u * l + 1u] = p1; + } // groups loop end + + twidCoefModifier = twidCoefModifier << 1u; + + // loop for stage + for (k = fftLen / 2; k > 2; k = k >> 1) + { + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + // loop for groups + for (j = 0; j < n2; j++) + { + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + // loop for butterfly + for (i = j; i < fftLen; i += n1) + { + l = i + n2; + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u; + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u; + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multSub_32x32_keep32_R(p0, yt, sinVal); + multAcc_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2u * l] = p0; + pSrc[2u * l + 1u] = p1; + } // butterfly loop end + + } // groups loop end + + twidCoefModifier = twidCoefModifier << 1u; + } // stages loop end + + n1 = n2; + n2 = n2 >> 1; + ia = 0; + + cosVal = pCoef[ia * 2]; + sinVal = pCoef[(ia * 2) + 1]; + ia = ia + twidCoefModifier; + + // loop for butterfly + for (i = 0; i < fftLen; i += n1) + { + l = i + n2; + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]); + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]); + + pSrc[2u * l] = xt; + + pSrc[2u * l + 1u] = yt; + + i += n1; + l = i + n2; + + xt = pSrc[2 * i] - pSrc[2 * l]; + pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]); + + yt = pSrc[2 * i + 1] - pSrc[2 * l + 1]; + pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]); + + pSrc[2u * l] = xt; + + pSrc[2u * l + 1u] = yt; + + } // butterfly loop end + +} |