mbed official
CMSIS DSP library
Dependents: KL25Z_FFT_Demo Hat_Board_v5_1 KL25Z_FFT_Demo_tony KL25Z_FFT_Demo_tony ... more
Fork of
mbed-dsp
by 
mbed official
Diff: cmsis_dsp/TransformFunctions/arm_cfft_radix2_q31.c
- Revision:
- 3:7a284390b0ce
- Parent:
- 2:da51fb522205
--- a/cmsis_dsp/TransformFunctions/arm_cfft_radix2_q31.c Thu May 30 17:10:11 2013 +0100
+++ b/cmsis_dsp/TransformFunctions/arm_cfft_radix2_q31.c Fri Nov 08 13:45:10 2013 +0000
@@ -1,8 +1,8 @@
/* ----------------------------------------------------------------------
-* Copyright (C) 2010 ARM Limited. All rights reserved.
+* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
*
-* $Date: 15. February 2012
-* $Revision: V1.1.0
+* $Date: 17. January 2013
+* $Revision: V1.4.1
*
* Project: CMSIS DSP Library
* Title: arm_cfft_radix2_q31.c
@@ -12,299 +12,339 @@
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
-* Version 1.1.0 2012/02/15
-* Updated with more optimizations, bug fixes and minor API changes.
-*
-* Version 0.0.3 2010/03/10
-* Initial version
+* 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"
-/**
- * @ingroup groupTransforms
- */
-
-/**
- * @defgroup Radix2_CFFT_CIFFT Radix-2 Complex FFT Functions
- *
- * \par
- * Complex Fast Fourier Transform(CFFT) and Complex Inverse Fast Fourier Transform(CIFFT) is an efficient algorithm to compute Discrete Fourier Transform(DFT) and Inverse Discrete Fourier Transform(IDFT).
- * Computational complexity of CFFT reduces drastically when compared to DFT.
- */
-
-
-/**
- * @addtogroup Radix2_CFFT_CIFFT
- * @{
- */
-
-/**
- * @details
- * @brief Processing function for the fixed-point CFFT/CIFFT.
- * @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 Radix2_CFFT_CIFFT group
- */
-
void arm_radix2_butterfly_q31(
q31_t * pSrc,
uint32_t fftLen,
q31_t * pCoef,
- uint16_t twidCoefModifier)
+ 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.
+* @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)
{
- int i, j, k, l;
- int n1, n2, ia;
- q31_t xt, yt, cosVal, sinVal;
-
- //N = fftLen;
- n2 = fftLen;
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
+ 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);
+ }
- // loop for groups
- for (i = 0; i < n2; i++)
- {
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
+ arm_bitreversal_q31(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
+}
- l = i + n2;
- xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
- pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+/**
+* @} end of ComplexFFT group
+*/
- yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
- pSrc[2 * i + 1] =
- ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
-
- pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) +
- ((int32_t) (((q63_t) yt * sinVal) >> 32)));
-
- pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) -
- ((int32_t) (((q63_t) xt * sinVal) >> 32)));
-
- } // groups loop end
+void arm_radix2_butterfly_q31(
+q31_t * pSrc,
+uint32_t fftLen,
+q31_t * pCoef,
+uint16_t twidCoefModifier)
+{
- twidCoefModifier = twidCoefModifier << 1u;
+ unsigned i, j, k, l, m;
+ unsigned n1, n2, ia;
+ q31_t xt, yt, cosVal, sinVal;
+ q31_t p0, p1;
+
+ //N = fftLen;
+ n2 = fftLen;
- // loop for stage
- for (k = fftLen / 2; k > 2; k = k >> 1)
- {
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- // loop for groups
- for (j = 0; j < n2; j++)
- {
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
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;
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 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;
- pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) +
- ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+ } // groups loop end
+
+ twidCoefModifier <<= 1u;
- pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) -
- ((int32_t) (((q63_t) xt * sinVal) >> 32)));
-
- } // butterfly loop end
-
- } // groups loop end
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- twidCoefModifier = twidCoefModifier << 1u;
- } // stages loop end
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
+ // 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;
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
+ 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
- // 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]);
+ } // groups loop end
+
+ twidCoefModifier <<= 1u;
+ } // stages loop end
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- pSrc[2u * l] = xt;
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
- pSrc[2u * l + 1u] = yt;
+ // 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]);
- i += n1;
- l = i + n2;
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+ i += n1;
+ l = i + n2;
+
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
- pSrc[2u * l] = xt;
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
- pSrc[2u * l + 1u] = yt;
+ pSrc[2u * l] = xt;
- } // butterfly loop end
+ 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)
+q31_t * pSrc,
+uint32_t fftLen,
+q31_t * pCoef,
+uint16_t twidCoefModifier)
{
- int i, j, k, l;
- int n1, n2, ia;
- q31_t xt, yt, cosVal, sinVal;
-
- //N = fftLen;
- n2 = fftLen;
-
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
+ unsigned i, j, k, l;
+ unsigned n1, n2, ia;
+ q31_t xt, yt, cosVal, sinVal;
+ q31_t p0, p1;
- // 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] >> 2u) - (pSrc[2 * l] >> 2u);
- pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+ //N = fftLen;
+ n2 = fftLen;
- yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
- pSrc[2 * i + 1] =
- ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
-
- pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) -
- ((int32_t) (((q63_t) yt * sinVal) >> 32)));
-
- pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) +
- ((int32_t) (((q63_t) xt * sinVal) >> 32)));
-
- } // groups loop end
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- 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++)
- {
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
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;
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 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;
+ } // groups loop end
- pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) -
- ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+ twidCoefModifier = twidCoefModifier << 1u;
- pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) +
- ((int32_t) (((q63_t) xt * sinVal) >> 32)));
-
- } // butterfly loop end
-
- } // groups loop end
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- twidCoefModifier = twidCoefModifier << 1u;
- } // stages loop end
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
- n1 = n2;
- n2 = n2 >> 1;
- ia = 0;
+ // 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;
- cosVal = pCoef[ia * 2];
- sinVal = pCoef[(ia * 2) + 1];
- ia = ia + twidCoefModifier;
+ 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
- // 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]);
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
- pSrc[2u * l] = xt;
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
- pSrc[2u * l + 1u] = yt;
+ // 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]);
- i += n1;
- l = i + n2;
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
- xt = pSrc[2 * i] - pSrc[2 * l];
- pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
- yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
- pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+ i += n1;
+ l = i + n2;
+
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
- pSrc[2u * l] = xt;
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
- pSrc[2u * l + 1u] = yt;
+ pSrc[2u * l] = xt;
- } // butterfly loop end
+ pSrc[2u * l + 1u] = yt;
+
+ } // butterfly loop end
}