Eli Hughes
V4.0.1 of the ARM CMSIS DSP libraries. Note that arm_bitreversal2.s, arm_cfft_f32.c and arm_rfft_fast_f32.c had to be removed. arm_bitreversal2.s will not assemble with the online tools. So, the fast f32 FFT functions are not yet available. All the other FFT functions are available.
Dependents: MPU9150_Example fir_f32 fir_f32 MPU9150_nucleo_noni2cdev ... more
TransformFunctions/arm_cfft_radix2_q15.c
- Committer:
- emh203
- Date:
- 2014-07-28
- Revision:
- 0:3d9c67d97d6f
File content as of revision 0:3d9c67d97d6f:
/* ----------------------------------------------------------------------
* Copyright (C) 2010-2014 ARM Limited. All rights reserved.
*
* $Date: 12. March 2014
* $Revision: V1.4.3
*
* Project: CMSIS DSP Library
* Title: arm_cfft_radix2_q15.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_q15(
q15_t * pSrc,
uint32_t fftLen,
q15_t * pCoef,
uint16_t twidCoefModifier);
void arm_radix2_butterfly_inverse_q15(
q15_t * pSrc,
uint32_t fftLen,
q15_t * pCoef,
uint16_t twidCoefModifier);
void arm_bitreversal_q15(
q15_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_q15(
const arm_cfft_radix2_instance_q15 * S,
q15_t * pSrc)
{
if(S->ifftFlag == 1u)
{
arm_radix2_butterfly_inverse_q15(pSrc, S->fftLen,
S->pTwiddle, S->twidCoefModifier);
}
else
{
arm_radix2_butterfly_q15(pSrc, S->fftLen,
S->pTwiddle, S->twidCoefModifier);
}
arm_bitreversal_q15(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
}
/**
* @} end of ComplexFFT group
*/
void arm_radix2_butterfly_q15(
q15_t * pSrc,
uint32_t fftLen,
q15_t * pCoef,
uint16_t twidCoefModifier)
{
#ifndef ARM_MATH_CM0_FAMILY
unsigned i, j, k, l;
unsigned n1, n2, ia;
q15_t in;
q31_t T, S, R;
q31_t coeff, out1, out2;
//N = fftLen;
n2 = fftLen;
n1 = n2;
n2 = n2 >> 1;
ia = 0;
// loop for groups
for (i = 0; i < n2; i++)
{
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
in = ((int16_t) (T & 0xFFFF)) >> 1;
T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
S = _SIMD32_OFFSET(pSrc + (2 * l));
in = ((int16_t) (S & 0xFFFF)) >> 1;
S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUAD(coeff, R) >> 16;
out2 = __SMUSDX(coeff, R);
#else
out1 = __SMUSDX(R, coeff) >> 16u;
out2 = __SMUAD(coeff, R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
i++;
l++;
T = _SIMD32_OFFSET(pSrc + (2 * i));
in = ((int16_t) (T & 0xFFFF)) >> 1;
T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
S = _SIMD32_OFFSET(pSrc + (2 * l));
in = ((int16_t) (S & 0xFFFF)) >> 1;
S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUAD(coeff, R) >> 16;
out2 = __SMUSDX(coeff, R);
#else
out1 = __SMUSDX(R, coeff) >> 16u;
out2 = __SMUAD(coeff, R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
} // 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++)
{
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
for (i = j; i < fftLen; i += n1)
{
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUAD(coeff, R) >> 16;
out2 = __SMUSDX(coeff, R);
#else
out1 = __SMUSDX(R, coeff) >> 16u;
out2 = __SMUAD(coeff, R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
i += n1;
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUAD(coeff, R) >> 16;
out2 = __SMUSDX(coeff, R);
#else
out1 = __SMUSDX(R, coeff) >> 16u;
out2 = __SMUAD(coeff, R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
} // butterfly loop end
} // groups loop end
twidCoefModifier = twidCoefModifier << 1u;
} // stages loop end
n1 = n2;
n2 = n2 >> 1;
ia = 0;
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
for (i = 0; i < fftLen; i += n1)
{
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
_SIMD32_OFFSET(pSrc + (2u * l)) = R;
i += n1;
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
_SIMD32_OFFSET(pSrc + (2u * l)) = R;
} // groups loop end
#else
unsigned i, j, k, l;
unsigned n1, n2, ia;
q15_t xt, yt, cosVal, sinVal;
//N = fftLen;
n2 = fftLen;
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] >> 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;
pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
((int16_t) (((q31_t) yt * sinVal) >> 16)));
pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
((int16_t) (((q31_t) xt * sinVal) >> 16)));
} // butterfly loop end
} // 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;
pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) +
((int16_t) (((q31_t) yt * sinVal) >> 16)));
pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) -
((int16_t) (((q31_t) xt * sinVal) >> 16)));
} // butterfly loop end
} // groups loop end
twidCoefModifier = twidCoefModifier << 1u;
} // stages loop end
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]);
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
} // groups loop end
twidCoefModifier = twidCoefModifier << 1u;
#endif // #ifndef ARM_MATH_CM0_FAMILY
}
void arm_radix2_butterfly_inverse_q15(
q15_t * pSrc,
uint32_t fftLen,
q15_t * pCoef,
uint16_t twidCoefModifier)
{
#ifndef ARM_MATH_CM0_FAMILY
unsigned i, j, k, l;
unsigned n1, n2, ia;
q15_t in;
q31_t T, S, R;
q31_t coeff, out1, out2;
//N = fftLen;
n2 = fftLen;
n1 = n2;
n2 = n2 >> 1;
ia = 0;
// loop for groups
for (i = 0; i < n2; i++)
{
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
in = ((int16_t) (T & 0xFFFF)) >> 1;
T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
S = _SIMD32_OFFSET(pSrc + (2 * l));
in = ((int16_t) (S & 0xFFFF)) >> 1;
S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUSD(coeff, R) >> 16;
out2 = __SMUADX(coeff, R);
#else
out1 = __SMUADX(R, coeff) >> 16u;
out2 = __SMUSD(__QSUB(0, coeff), R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
i++;
l++;
T = _SIMD32_OFFSET(pSrc + (2 * i));
in = ((int16_t) (T & 0xFFFF)) >> 1;
T = ((T >> 1) & 0xFFFF0000) | (in & 0xFFFF);
S = _SIMD32_OFFSET(pSrc + (2 * l));
in = ((int16_t) (S & 0xFFFF)) >> 1;
S = ((S >> 1) & 0xFFFF0000) | (in & 0xFFFF);
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUSD(coeff, R) >> 16;
out2 = __SMUADX(coeff, R);
#else
out1 = __SMUADX(R, coeff) >> 16u;
out2 = __SMUSD(__QSUB(0, coeff), R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
} // 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++)
{
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
for (i = j; i < fftLen; i += n1)
{
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUSD(coeff, R) >> 16;
out2 = __SMUADX(coeff, R);
#else
out1 = __SMUADX(R, coeff) >> 16u;
out2 = __SMUSD(__QSUB(0, coeff), R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
i += n1;
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __SHADD16(T, S);
#ifndef ARM_MATH_BIG_ENDIAN
out1 = __SMUSD(coeff, R) >> 16;
out2 = __SMUADX(coeff, R);
#else
out1 = __SMUADX(R, coeff) >> 16u;
out2 = __SMUSD(__QSUB(0, coeff), R);
#endif // #ifndef ARM_MATH_BIG_ENDIAN
_SIMD32_OFFSET(pSrc + (2u * l)) =
(q31_t) ((out2) & 0xFFFF0000) | (out1 & 0x0000FFFF);
} // butterfly loop end
} // groups loop end
twidCoefModifier = twidCoefModifier << 1u;
} // stages loop end
n1 = n2;
n2 = n2 >> 1;
ia = 0;
// loop for groups
for (j = 0; j < n2; j++)
{
coeff = _SIMD32_OFFSET(pCoef + (ia * 2u));
ia = ia + twidCoefModifier;
// loop for butterfly
for (i = j; i < fftLen; i += n1)
{
l = i + n2;
T = _SIMD32_OFFSET(pSrc + (2 * i));
S = _SIMD32_OFFSET(pSrc + (2 * l));
R = __QSUB16(T, S);
_SIMD32_OFFSET(pSrc + (2 * i)) = __QADD16(T, S);
_SIMD32_OFFSET(pSrc + (2u * l)) = R;
} // butterfly loop end
} // groups loop end
twidCoefModifier = twidCoefModifier << 1u;
#else
unsigned i, j, k, l;
unsigned n1, n2, ia;
q15_t xt, yt, cosVal, sinVal;
//N = fftLen;
n2 = fftLen;
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] >> 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;
pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
((int16_t) (((q31_t) yt * sinVal) >> 16)));
pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
((int16_t) (((q31_t) xt * sinVal) >> 16)));
} // butterfly loop end
} // 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;
pSrc[2u * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16)) -
((int16_t) (((q31_t) yt * sinVal) >> 16)));
pSrc[2u * l + 1u] = (((int16_t) (((q31_t) yt * cosVal) >> 16)) +
((int16_t) (((q31_t) xt * sinVal) >> 16)));
} // 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;
} // groups loop end
#endif // #ifndef ARM_MATH_CM0_FAMILY
}