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Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_cfft_radix4_f32.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_cfft_radix4_f32.c | 1210 |
1 files changed, 1210 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_cfft_radix4_f32.c b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_cfft_radix4_f32.c new file mode 100644 index 0000000000..5acaf768b4 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_cfft_radix4_f32.c @@ -0,0 +1,1210 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2013 ARM Limited. All rights reserved. +* +* $Date: 17. January 2013 +* $Revision: V1.4.1 +* +* Project: CMSIS DSP Library +* Title: arm_cfft_radix4_f32.c +* +* Description: Radix-4 Decimation in Frequency CFFT & CIFFT Floating 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" + +extern void arm_bitreversal_f32( +float32_t * pSrc, +uint16_t fftSize, +uint16_t bitRevFactor, +uint16_t * pBitRevTab); + +/** +* @ingroup groupTransforms +*/ + +/* ---------------------------------------------------------------------- +** Internal helper function used by the FFTs +** ------------------------------------------------------------------- */ + +/* +* @brief Core function for the floating-point CFFT butterfly process. +* @param[in, out] *pSrc points to the in-place buffer of floating-point 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_f32( +float32_t * pSrc, +uint16_t fftLen, +float32_t * pCoef, +uint16_t twidCoefModifier) +{ + + float32_t co1, co2, co3, si1, si2, si3; + uint32_t ia1, ia2, ia3; + uint32_t i0, i1, i2, i3; + uint32_t n1, n2, j, k; + +#ifndef ARM_MATH_CM0_FAMILY_FAMILY + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + float32_t xaIn, yaIn, xbIn, ybIn, xcIn, ycIn, xdIn, ydIn; + float32_t Xaplusc, Xbplusd, Yaplusc, Ybplusd, Xaminusc, Xbminusd, Yaminusc, + Ybminusd; + float32_t Xb12C_out, Yb12C_out, Xc12C_out, Yc12C_out, Xd12C_out, Yd12C_out; + float32_t Xb12_out, Yb12_out, Xc12_out, Yc12_out, Xd12_out, Yd12_out; + float32_t *ptr1; + float32_t p0,p1,p2,p3,p4,p5; + float32_t a0,a1,a2,a3,a4,a5,a6,a7; + + /* Initializations for the first stage */ + n2 = fftLen; + n1 = n2; + + /* n2 = fftLen/4 */ + n2 >>= 2u; + i0 = 0u; + ia1 = 0u; + + j = n2; + + /* Calculation of first stage */ + 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; + + xaIn = pSrc[(2u * i0)]; + yaIn = pSrc[(2u * i0) + 1u]; + + xbIn = pSrc[(2u * i1)]; + ybIn = pSrc[(2u * i1) + 1u]; + + xcIn = pSrc[(2u * i2)]; + ycIn = pSrc[(2u * i2) + 1u]; + + xdIn = pSrc[(2u * i3)]; + ydIn = pSrc[(2u * i3) + 1u]; + + /* xa + xc */ + Xaplusc = xaIn + xcIn; + /* xb + xd */ + Xbplusd = xbIn + xdIn; + /* ya + yc */ + Yaplusc = yaIn + ycIn; + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* index calculation for the coefficients */ + ia2 = ia1 + ia1; + co2 = pCoef[ia2 * 2u]; + si2 = pCoef[(ia2 * 2u) + 1u]; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + /* xb - xd */ + Xbminusd = xbIn - xdIn; + /* ya - yc */ + Yaminusc = yaIn - ycIn; + /* yb - yd */ + Ybminusd = ybIn - ydIn; + + /* xa' = xa + xb + xc + xd */ + pSrc[(2u * i0)] = Xaplusc + Xbplusd; + /* ya' = ya + yb + yc + yd */ + pSrc[(2u * i0) + 1u] = Yaplusc + Ybplusd; + + /* (xa - xc) + (yb - yd) */ + Xb12C_out = (Xaminusc + Ybminusd); + /* (ya - yc) + (xb - xd) */ + Yb12C_out = (Yaminusc - Xbminusd); + /* (xa + xc) - (xb + xd) */ + Xc12C_out = (Xaplusc - Xbplusd); + /* (ya + yc) - (yb + yd) */ + Yc12C_out = (Yaplusc - Ybplusd); + /* (xa - xc) - (yb - yd) */ + Xd12C_out = (Xaminusc - Ybminusd); + /* (ya - yc) + (xb - xd) */ + Yd12C_out = (Xbminusd + Yaminusc); + + co1 = pCoef[ia1 * 2u]; + si1 = pCoef[(ia1 * 2u) + 1u]; + + /* index calculation for the coefficients */ + ia3 = ia2 + ia1; + co3 = pCoef[ia3 * 2u]; + si3 = pCoef[(ia3 * 2u) + 1u]; + + Xb12_out = Xb12C_out * co1; + Yb12_out = Yb12C_out * co1; + Xc12_out = Xc12C_out * co2; + Yc12_out = Yc12C_out * co2; + Xd12_out = Xd12C_out * co3; + Yd12_out = Yd12C_out * co3; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + //Xb12_out -= Yb12C_out * si1; + p0 = Yb12C_out * si1; + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + //Yb12_out += Xb12C_out * si1; + p1 = Xb12C_out * si1; + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + //Xc12_out -= Yc12C_out * si2; + p2 = Yc12C_out * si2; + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + //Yc12_out += Xc12C_out * si2; + p3 = Xc12C_out * si2; + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + //Xd12_out -= Yd12C_out * si3; + p4 = Yd12C_out * si3; + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + //Yd12_out += Xd12C_out * si3; + p5 = Xd12C_out * si3; + + Xb12_out += p0; + Yb12_out -= p1; + Xc12_out += p2; + Yc12_out -= p3; + Xd12_out += p4; + Yd12_out -= p5; + + /* xc' = (xa-xb+xc-xd)co2 + (ya-yb+yc-yd)(si2) */ + pSrc[2u * i1] = Xc12_out; + + /* yc' = (ya-yb+yc-yd)co2 - (xa-xb+xc-xd)(si2) */ + pSrc[(2u * i1) + 1u] = Yc12_out; + + /* xb' = (xa+yb-xc-yd)co1 + (ya-xb-yc+xd)(si1) */ + pSrc[2u * i2] = Xb12_out; + + /* yb' = (ya-xb-yc+xd)co1 - (xa+yb-xc-yd)(si1) */ + pSrc[(2u * i2) + 1u] = Yb12_out; + + /* xd' = (xa-yb-xc+yd)co3 + (ya+xb-yc-xd)(si3) */ + pSrc[2u * i3] = Xd12_out; + + /* yd' = (ya+xb-yc-xd)co3 - (xa-yb-xc+yd)(si3) */ + pSrc[(2u * i3) + 1u] = Yd12_out; + + /* Twiddle coefficients index modifier */ + ia1 += twidCoefModifier; + + /* Updating input index */ + i0++; + + } + while(--j); + + twidCoefModifier <<= 2u; + + /* Calculation of second stage to excluding last stage */ + for (k = fftLen >> 2u; k > 4u; k >>= 2u) + { + /* Initializations for the first stage */ + n1 = n2; + n2 >>= 2u; + ia1 = 0u; + + /* Calculation of first stage */ + 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 += 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; + + xaIn = pSrc[(2u * i0)]; + yaIn = pSrc[(2u * i0) + 1u]; + + xbIn = pSrc[(2u * i1)]; + ybIn = pSrc[(2u * i1) + 1u]; + + xcIn = pSrc[(2u * i2)]; + ycIn = pSrc[(2u * i2) + 1u]; + + xdIn = pSrc[(2u * i3)]; + ydIn = pSrc[(2u * i3) + 1u]; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + /* (xb - xd) */ + Xbminusd = xbIn - xdIn; + /* ya - yc */ + Yaminusc = yaIn - ycIn; + /* (yb - yd) */ + Ybminusd = ybIn - ydIn; + + /* xa + xc */ + Xaplusc = xaIn + xcIn; + /* xb + xd */ + Xbplusd = xbIn + xdIn; + /* ya + yc */ + Yaplusc = yaIn + ycIn; + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* (xa - xc) + (yb - yd) */ + Xb12C_out = (Xaminusc + Ybminusd); + /* (ya - yc) - (xb - xd) */ + Yb12C_out = (Yaminusc - Xbminusd); + /* xa + xc -(xb + xd) */ + Xc12C_out = (Xaplusc - Xbplusd); + /* (ya + yc) - (yb + yd) */ + Yc12C_out = (Yaplusc - Ybplusd); + /* (xa - xc) - (yb - yd) */ + Xd12C_out = (Xaminusc - Ybminusd); + /* (ya - yc) + (xb - xd) */ + Yd12C_out = (Xbminusd + Yaminusc); + + pSrc[(2u * i0)] = Xaplusc + Xbplusd; + pSrc[(2u * i0) + 1u] = Yaplusc + Ybplusd; + + Xb12_out = Xb12C_out * co1; + Yb12_out = Yb12C_out * co1; + Xc12_out = Xc12C_out * co2; + Yc12_out = Yc12C_out * co2; + Xd12_out = Xd12C_out * co3; + Yd12_out = Yd12C_out * co3; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + //Xb12_out -= Yb12C_out * si1; + p0 = Yb12C_out * si1; + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + //Yb12_out += Xb12C_out * si1; + p1 = Xb12C_out * si1; + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + //Xc12_out -= Yc12C_out * si2; + p2 = Yc12C_out * si2; + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + //Yc12_out += Xc12C_out * si2; + p3 = Xc12C_out * si2; + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + //Xd12_out -= Yd12C_out * si3; + p4 = Yd12C_out * si3; + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + //Yd12_out += Xd12C_out * si3; + p5 = Xd12C_out * si3; + + Xb12_out += p0; + Yb12_out -= p1; + Xc12_out += p2; + Yc12_out -= p3; + Xd12_out += p4; + Yd12_out -= p5; + + /* xc' = (xa-xb+xc-xd)co2 + (ya-yb+yc-yd)(si2) */ + pSrc[2u * i1] = Xc12_out; + + /* yc' = (ya-yb+yc-yd)co2 - (xa-xb+xc-xd)(si2) */ + pSrc[(2u * i1) + 1u] = Yc12_out; + + /* xb' = (xa+yb-xc-yd)co1 + (ya-xb-yc+xd)(si1) */ + pSrc[2u * i2] = Xb12_out; + + /* yb' = (ya-xb-yc+xd)co1 - (xa+yb-xc-yd)(si1) */ + pSrc[(2u * i2) + 1u] = Yb12_out; + + /* xd' = (xa-yb-xc+yd)co3 + (ya+xb-yc-xd)(si3) */ + pSrc[2u * i3] = Xd12_out; + + /* yd' = (ya+xb-yc-xd)co3 - (xa-yb-xc+yd)(si3) */ + pSrc[(2u * i3) + 1u] = Yd12_out; + + i0 += n1; + } while(i0 < fftLen); + j++; + } while(j <= (n2 - 1u)); + twidCoefModifier <<= 2u; + } + + j = fftLen >> 2; + ptr1 = &pSrc[0]; + + /* Calculations of last stage */ + do + { + xaIn = ptr1[0]; + yaIn = ptr1[1]; + xbIn = ptr1[2]; + ybIn = ptr1[3]; + xcIn = ptr1[4]; + ycIn = ptr1[5]; + xdIn = ptr1[6]; + ydIn = ptr1[7]; + + /* xa + xc */ + Xaplusc = xaIn + xcIn; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + + /* ya + yc */ + Yaplusc = yaIn + ycIn; + + /* ya - yc */ + Yaminusc = yaIn - ycIn; + + /* xb + xd */ + Xbplusd = xbIn + xdIn; + + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* (xb-xd) */ + Xbminusd = xbIn - xdIn; + + /* (yb-yd) */ + Ybminusd = ybIn - ydIn; + + /* xa' = xa + xb + xc + xd */ + a0 = (Xaplusc + Xbplusd); + /* ya' = ya + yb + yc + yd */ + a1 = (Yaplusc + Ybplusd); + /* xc' = (xa-xb+xc-xd) */ + a2 = (Xaplusc - Xbplusd); + /* yc' = (ya-yb+yc-yd) */ + a3 = (Yaplusc - Ybplusd); + /* xb' = (xa+yb-xc-yd) */ + a4 = (Xaminusc + Ybminusd); + /* yb' = (ya-xb-yc+xd) */ + a5 = (Yaminusc - Xbminusd); + /* xd' = (xa-yb-xc+yd)) */ + a6 = (Xaminusc - Ybminusd); + /* yd' = (ya+xb-yc-xd) */ + a7 = (Xbminusd + Yaminusc); + + ptr1[0] = a0; + ptr1[1] = a1; + ptr1[2] = a2; + ptr1[3] = a3; + ptr1[4] = a4; + ptr1[5] = a5; + ptr1[6] = a6; + ptr1[7] = a7; + + /* increment pointer by 8 */ + ptr1 += 8u; + } while(--j); + +#else + + float32_t t1, t2, r1, r2, s1, s2; + + /* Run the below code for Cortex-M0 */ + + /* 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; + } + +#endif /* #ifndef ARM_MATH_CM0_FAMILY_FAMILY */ + +} + +/* +* @brief Core function for the floating-point CIFFT butterfly process. +* @param[in, out] *pSrc points to the in-place buffer of floating-point data type. +* @param[in] fftLen length of the FFT. +* @param[in] *pCoef points to twiddle coefficient buffer. +* @param[in] twidCoefModifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table. +* @param[in] onebyfftLen value of 1/fftLen. +* @return none. +*/ + +void arm_radix4_butterfly_inverse_f32( +float32_t * pSrc, +uint16_t fftLen, +float32_t * pCoef, +uint16_t twidCoefModifier, +float32_t onebyfftLen) +{ + float32_t co1, co2, co3, si1, si2, si3; + uint32_t ia1, ia2, ia3; + uint32_t i0, i1, i2, i3; + uint32_t n1, n2, j, k; + +#ifndef ARM_MATH_CM0_FAMILY_FAMILY + + float32_t xaIn, yaIn, xbIn, ybIn, xcIn, ycIn, xdIn, ydIn; + float32_t Xaplusc, Xbplusd, Yaplusc, Ybplusd, Xaminusc, Xbminusd, Yaminusc, + Ybminusd; + float32_t Xb12C_out, Yb12C_out, Xc12C_out, Yc12C_out, Xd12C_out, Yd12C_out; + float32_t Xb12_out, Yb12_out, Xc12_out, Yc12_out, Xd12_out, Yd12_out; + float32_t *ptr1; + float32_t p0,p1,p2,p3,p4,p5,p6,p7; + float32_t a0,a1,a2,a3,a4,a5,a6,a7; + + + /* Initializations for the first stage */ + n2 = fftLen; + n1 = n2; + + /* n2 = fftLen/4 */ + n2 >>= 2u; + i0 = 0u; + ia1 = 0u; + + j = n2; + + /* Calculation of first stage */ + 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; + + /* Butterfly implementation */ + xaIn = pSrc[(2u * i0)]; + yaIn = pSrc[(2u * i0) + 1u]; + + xcIn = pSrc[(2u * i2)]; + ycIn = pSrc[(2u * i2) + 1u]; + + xbIn = pSrc[(2u * i1)]; + ybIn = pSrc[(2u * i1) + 1u]; + + xdIn = pSrc[(2u * i3)]; + ydIn = pSrc[(2u * i3) + 1u]; + + /* xa + xc */ + Xaplusc = xaIn + xcIn; + /* xb + xd */ + Xbplusd = xbIn + xdIn; + /* ya + yc */ + Yaplusc = yaIn + ycIn; + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* index calculation for the coefficients */ + ia2 = ia1 + ia1; + co2 = pCoef[ia2 * 2u]; + si2 = pCoef[(ia2 * 2u) + 1u]; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + /* xb - xd */ + Xbminusd = xbIn - xdIn; + /* ya - yc */ + Yaminusc = yaIn - ycIn; + /* yb - yd */ + Ybminusd = ybIn - ydIn; + + /* xa' = xa + xb + xc + xd */ + pSrc[(2u * i0)] = Xaplusc + Xbplusd; + + /* ya' = ya + yb + yc + yd */ + pSrc[(2u * i0) + 1u] = Yaplusc + Ybplusd; + + /* (xa - xc) - (yb - yd) */ + Xb12C_out = (Xaminusc - Ybminusd); + /* (ya - yc) + (xb - xd) */ + Yb12C_out = (Yaminusc + Xbminusd); + /* (xa + xc) - (xb + xd) */ + Xc12C_out = (Xaplusc - Xbplusd); + /* (ya + yc) - (yb + yd) */ + Yc12C_out = (Yaplusc - Ybplusd); + /* (xa - xc) + (yb - yd) */ + Xd12C_out = (Xaminusc + Ybminusd); + /* (ya - yc) - (xb - xd) */ + Yd12C_out = (Yaminusc - Xbminusd); + + co1 = pCoef[ia1 * 2u]; + si1 = pCoef[(ia1 * 2u) + 1u]; + + /* index calculation for the coefficients */ + ia3 = ia2 + ia1; + co3 = pCoef[ia3 * 2u]; + si3 = pCoef[(ia3 * 2u) + 1u]; + + Xb12_out = Xb12C_out * co1; + Yb12_out = Yb12C_out * co1; + Xc12_out = Xc12C_out * co2; + Yc12_out = Yc12C_out * co2; + Xd12_out = Xd12C_out * co3; + Yd12_out = Yd12C_out * co3; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + //Xb12_out -= Yb12C_out * si1; + p0 = Yb12C_out * si1; + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + //Yb12_out += Xb12C_out * si1; + p1 = Xb12C_out * si1; + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + //Xc12_out -= Yc12C_out * si2; + p2 = Yc12C_out * si2; + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + //Yc12_out += Xc12C_out * si2; + p3 = Xc12C_out * si2; + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + //Xd12_out -= Yd12C_out * si3; + p4 = Yd12C_out * si3; + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + //Yd12_out += Xd12C_out * si3; + p5 = Xd12C_out * si3; + + Xb12_out -= p0; + Yb12_out += p1; + Xc12_out -= p2; + Yc12_out += p3; + Xd12_out -= p4; + Yd12_out += p5; + + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + pSrc[2u * i1] = Xc12_out; + + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + pSrc[(2u * i1) + 1u] = Yc12_out; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + pSrc[2u * i2] = Xb12_out; + + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + pSrc[(2u * i2) + 1u] = Yb12_out; + + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + pSrc[2u * i3] = Xd12_out; + + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + pSrc[(2u * i3) + 1u] = Yd12_out; + + /* Twiddle coefficients index modifier */ + ia1 = ia1 + twidCoefModifier; + + /* Updating input index */ + i0 = i0 + 1u; + + } while(--j); + + twidCoefModifier <<= 2u; + + /* Calculation of second stage to excluding last stage */ + for (k = fftLen >> 2u; k > 4u; k >>= 2u) + { + /* Initializations for the first stage */ + n1 = n2; + n2 >>= 2u; + ia1 = 0u; + + /* Calculation of first stage */ + 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; + + xaIn = pSrc[(2u * i0)]; + yaIn = pSrc[(2u * i0) + 1u]; + + xbIn = pSrc[(2u * i1)]; + ybIn = pSrc[(2u * i1) + 1u]; + + xcIn = pSrc[(2u * i2)]; + ycIn = pSrc[(2u * i2) + 1u]; + + xdIn = pSrc[(2u * i3)]; + ydIn = pSrc[(2u * i3) + 1u]; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + /* (xb - xd) */ + Xbminusd = xbIn - xdIn; + /* ya - yc */ + Yaminusc = yaIn - ycIn; + /* (yb - yd) */ + Ybminusd = ybIn - ydIn; + + /* xa + xc */ + Xaplusc = xaIn + xcIn; + /* xb + xd */ + Xbplusd = xbIn + xdIn; + /* ya + yc */ + Yaplusc = yaIn + ycIn; + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* (xa - xc) - (yb - yd) */ + Xb12C_out = (Xaminusc - Ybminusd); + /* (ya - yc) + (xb - xd) */ + Yb12C_out = (Yaminusc + Xbminusd); + /* xa + xc -(xb + xd) */ + Xc12C_out = (Xaplusc - Xbplusd); + /* (ya + yc) - (yb + yd) */ + Yc12C_out = (Yaplusc - Ybplusd); + /* (xa - xc) + (yb - yd) */ + Xd12C_out = (Xaminusc + Ybminusd); + /* (ya - yc) - (xb - xd) */ + Yd12C_out = (Yaminusc - Xbminusd); + + pSrc[(2u * i0)] = Xaplusc + Xbplusd; + pSrc[(2u * i0) + 1u] = Yaplusc + Ybplusd; + + Xb12_out = Xb12C_out * co1; + Yb12_out = Yb12C_out * co1; + Xc12_out = Xc12C_out * co2; + Yc12_out = Yc12C_out * co2; + Xd12_out = Xd12C_out * co3; + Yd12_out = Yd12C_out * co3; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + //Xb12_out -= Yb12C_out * si1; + p0 = Yb12C_out * si1; + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + //Yb12_out += Xb12C_out * si1; + p1 = Xb12C_out * si1; + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + //Xc12_out -= Yc12C_out * si2; + p2 = Yc12C_out * si2; + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + //Yc12_out += Xc12C_out * si2; + p3 = Xc12C_out * si2; + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + //Xd12_out -= Yd12C_out * si3; + p4 = Yd12C_out * si3; + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + //Yd12_out += Xd12C_out * si3; + p5 = Xd12C_out * si3; + + Xb12_out -= p0; + Yb12_out += p1; + Xc12_out -= p2; + Yc12_out += p3; + Xd12_out -= p4; + Yd12_out += p5; + + /* xc' = (xa-xb+xc-xd)co2 - (ya-yb+yc-yd)(si2) */ + pSrc[2u * i1] = Xc12_out; + + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + pSrc[(2u * i1) + 1u] = Yc12_out; + + /* xb' = (xa+yb-xc-yd)co1 - (ya-xb-yc+xd)(si1) */ + pSrc[2u * i2] = Xb12_out; + + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + pSrc[(2u * i2) + 1u] = Yb12_out; + + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + pSrc[2u * i3] = Xd12_out; + + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + pSrc[(2u * i3) + 1u] = Yd12_out; + + i0 += n1; + } while(i0 < fftLen); + j++; + } while(j <= (n2 - 1u)); + twidCoefModifier <<= 2u; + } + /* Initializations of last stage */ + + j = fftLen >> 2; + ptr1 = &pSrc[0]; + + /* Calculations of last stage */ + do + { + xaIn = ptr1[0]; + yaIn = ptr1[1]; + xbIn = ptr1[2]; + ybIn = ptr1[3]; + xcIn = ptr1[4]; + ycIn = ptr1[5]; + xdIn = ptr1[6]; + ydIn = ptr1[7]; + + /* Butterfly implementation */ + /* xa + xc */ + Xaplusc = xaIn + xcIn; + + /* xa - xc */ + Xaminusc = xaIn - xcIn; + + /* ya + yc */ + Yaplusc = yaIn + ycIn; + + /* ya - yc */ + Yaminusc = yaIn - ycIn; + + /* xb + xd */ + Xbplusd = xbIn + xdIn; + + /* yb + yd */ + Ybplusd = ybIn + ydIn; + + /* (xb-xd) */ + Xbminusd = xbIn - xdIn; + + /* (yb-yd) */ + Ybminusd = ybIn - ydIn; + + /* xa' = (xa+xb+xc+xd) * onebyfftLen */ + a0 = (Xaplusc + Xbplusd); + /* ya' = (ya+yb+yc+yd) * onebyfftLen */ + a1 = (Yaplusc + Ybplusd); + /* xc' = (xa-xb+xc-xd) * onebyfftLen */ + a2 = (Xaplusc - Xbplusd); + /* yc' = (ya-yb+yc-yd) * onebyfftLen */ + a3 = (Yaplusc - Ybplusd); + /* xb' = (xa-yb-xc+yd) * onebyfftLen */ + a4 = (Xaminusc - Ybminusd); + /* yb' = (ya+xb-yc-xd) * onebyfftLen */ + a5 = (Yaminusc + Xbminusd); + /* xd' = (xa-yb-xc+yd) * onebyfftLen */ + a6 = (Xaminusc + Ybminusd); + /* yd' = (ya-xb-yc+xd) * onebyfftLen */ + a7 = (Yaminusc - Xbminusd); + + p0 = a0 * onebyfftLen; + p1 = a1 * onebyfftLen; + p2 = a2 * onebyfftLen; + p3 = a3 * onebyfftLen; + p4 = a4 * onebyfftLen; + p5 = a5 * onebyfftLen; + p6 = a6 * onebyfftLen; + p7 = a7 * onebyfftLen; + + /* xa' = (xa+xb+xc+xd) * onebyfftLen */ + ptr1[0] = p0; + /* ya' = (ya+yb+yc+yd) * onebyfftLen */ + ptr1[1] = p1; + /* xc' = (xa-xb+xc-xd) * onebyfftLen */ + ptr1[2] = p2; + /* yc' = (ya-yb+yc-yd) * onebyfftLen */ + ptr1[3] = p3; + /* xb' = (xa-yb-xc+yd) * onebyfftLen */ + ptr1[4] = p4; + /* yb' = (ya+xb-yc-xd) * onebyfftLen */ + ptr1[5] = p5; + /* xd' = (xa-yb-xc+yd) * onebyfftLen */ + ptr1[6] = p6; + /* yd' = (ya-xb-yc+xd) * onebyfftLen */ + ptr1[7] = p7; + + /* increment source pointer by 8 for next calculations */ + ptr1 = ptr1 + 8u; + + } while(--j); + +#else + + float32_t t1, t2, r1, r2, s1, s2; + + /* Run the below code for Cortex-M0 */ + + /* Initializations for the first stage */ + n2 = fftLen; + n1 = n2; + + /* Calculation of first stage */ + for (k = fftLen; k > 4u; k >>= 2u) + { + /* Initializations for the first stage */ + n1 = n2; + n2 >>= 2u; + ia1 = 0u; + + /* Calculation of first stage */ + 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; + } + /* Initializations of last stage */ + n1 = n2; + n2 >>= 2u; + + /* Calculations of last stage */ + for (i0 = 0u; i0 <= (fftLen - n1); i0 += n1) + { + /* 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; + + /* Butterfly implementation */ + /* 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]; + + /* xc + xd */ + t1 = pSrc[2u * i1] + pSrc[2u * i3]; + + /* xa' = xa + xb + xc + xd */ + pSrc[2u * i0] = (r1 + t1) * onebyfftLen; + + /* (xa + xb) - (xc + 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) * onebyfftLen; + + /* (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 * onebyfftLen; + + /* yc' = (ya-yb+yc-yd)co2 + (xa-xb+xc-xd)(si2) */ + pSrc[(2u * i1) + 1u] = s1 * onebyfftLen; + + /* (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 * onebyfftLen; + + /* yb' = (ya-xb-yc+xd)co1 + (xa+yb-xc-yd)(si1) */ + pSrc[(2u * i2) + 1u] = s1 * onebyfftLen; + + /* xd' = (xa-yb-xc+yd)co3 - (ya+xb-yc-xd)(si3) */ + pSrc[2u * i3] = r2 * onebyfftLen; + + /* yd' = (ya+xb-yc-xd)co3 + (xa-yb-xc+yd)(si3) */ + pSrc[(2u * i3) + 1u] = s2 * onebyfftLen; + } + +#endif /* #ifndef ARM_MATH_CM0_FAMILY_FAMILY */ +} + +/** +* @addtogroup ComplexFFT +* @{ +*/ + +/** +* @details +* @brief Processing function for the floating-point Radix-4 CFFT/CIFFT. +* @deprecated Do not use this function. It has been superceded by \ref arm_cfft_f32 and will be removed +* in the future. +* @param[in] *S points to an instance of the floating-point Radix-4 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_radix4_f32( +const arm_cfft_radix4_instance_f32 * S, +float32_t * pSrc) +{ + + if(S->ifftFlag == 1u) + { + /* Complex IFFT radix-4 */ + arm_radix4_butterfly_inverse_f32(pSrc, S->fftLen, S->pTwiddle, + S->twidCoefModifier, S->onebyfftLen); + } + else + { + /* Complex FFT radix-4 */ + arm_radix4_butterfly_f32(pSrc, S->fftLen, S->pTwiddle, + S->twidCoefModifier); + } + + if(S->bitReverseFlag == 1u) + { + /* Bit Reversal */ + arm_bitreversal_f32(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable); + } + +} + +/** +* @} end of ComplexFFT group +*/ + |