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Diffstat (limited to 'DSP_Lib/Source/TransformFunctions/arm_cfft_radix8_f32.c')
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diff --git a/DSP_Lib/Source/TransformFunctions/arm_cfft_radix8_f32.c b/DSP_Lib/Source/TransformFunctions/arm_cfft_radix8_f32.c deleted file mode 100644 index 7ed8fde..0000000 --- a/DSP_Lib/Source/TransformFunctions/arm_cfft_radix8_f32.c +++ /dev/null @@ -1,384 +0,0 @@ -/* ---------------------------------------------------------------------- -* 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_radix8_f32.c -* -* Description: Radix-8 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" - -/** -* @ingroup groupTransforms -*/ - -/** -* @defgroup Radix8_CFFT_CIFFT Radix-8 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. -* \par -* This set of functions implements CFFT/CIFFT -* for floating-point data types. The functions operates on in-place buffer which uses same buffer for input and output. -* Complex input is stored in input buffer in an interleaved fashion. -* -* \par -* The functions operate on blocks of input and output data and each call to the function processes -* <code>2*fftLen</code> samples through the transform. <code>pSrc</code> points to In-place arrays containing <code>2*fftLen</code> values. -* \par -* The <code>pSrc</code> points to the array of in-place buffer of size <code>2*fftLen</code> and inputs and outputs are stored in an interleaved fashion as shown below. -* <pre> {real[0], imag[0], real[1], imag[1],..} </pre> -* -* \par Lengths supported by the transform: -* \par -* Internally, the function utilize a Radix-8 decimation in frequency(DIF) algorithm -* and the size of the FFT supported are of the lengths [ 64, 512, 4096]. -* -* -* \par Algorithm: -* -* <b>Complex Fast Fourier Transform:</b> -* \par -* Input real and imaginary data: -* <pre> -* x(n) = xa + j * ya -* x(n+N/4 ) = xb + j * yb -* x(n+N/2 ) = xc + j * yc -* x(n+3N 4) = xd + j * yd -* </pre> -* where N is length of FFT -* \par -* Output real and imaginary data: -* <pre> -* X(4r) = xa'+ j * ya' -* X(4r+1) = xb'+ j * yb' -* X(4r+2) = xc'+ j * yc' -* X(4r+3) = xd'+ j * yd' -* </pre> -* \par -* Twiddle factors for Radix-8 FFT: -* <pre> -* Wn = co1 + j * (- si1) -* W2n = co2 + j * (- si2) -* W3n = co3 + j * (- si3) -* </pre> -* -* \par -* \image html CFFT.gif "Radix-8 Decimation-in Frequency Complex Fast Fourier Transform" -* -* \par -* Output from Radix-8 CFFT Results in Digit reversal order. Interchange middle two branches of every butterfly results in Bit reversed output. -* \par -* <b> Butterfly CFFT equations:</b> -* <pre> -* xa' = xa + xb + xc + xd -* ya' = ya + yb + yc + yd -* xc' = (xa+yb-xc-yd)* co1 + (ya-xb-yc+xd)* (si1) -* yc' = (ya-xb-yc+xd)* co1 - (xa+yb-xc-yd)* (si1) -* xb' = (xa-xb+xc-xd)* co2 + (ya-yb+yc-yd)* (si2) -* yb' = (ya-yb+yc-yd)* co2 - (xa-xb+xc-xd)* (si2) -* xd' = (xa-yb-xc+yd)* co3 + (ya+xb-yc-xd)* (si3) -* yd' = (ya+xb-yc-xd)* co3 - (xa-yb-xc+yd)* (si3) -* </pre> -* -* \par -* where <code>fftLen</code> length of CFFT/CIFFT; <code>ifftFlag</code> Flag for selection of CFFT or CIFFT(Set ifftFlag to calculate CIFFT otherwise calculates CFFT); -* <code>bitReverseFlag</code> Flag for selection of output order(Set bitReverseFlag to output in normal order otherwise output in bit reversed order); -* <code>pTwiddle</code>points to array of twiddle coefficients; <code>pBitRevTable</code> points to the array of bit reversal table. -* <code>twidCoefModifier</code> modifier for twiddle factor table which supports all FFT lengths with same table; -* <code>pBitRevTable</code> modifier for bit reversal table which supports all FFT lengths with same table. -* <code>onebyfftLen</code> value of 1/fftLen to calculate CIFFT; -* -* \par Fixed-Point Behavior -* Care must be taken when using the fixed-point versions of the CFFT/CIFFT function. -* Refer to the function specific documentation below for usage guidelines. -*/ - - -/* -* @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_radix8_butterfly_f32( -float32_t * pSrc, -uint16_t fftLen, -const float32_t * pCoef, -uint16_t twidCoefModifier) -{ - uint32_t ia1, ia2, ia3, ia4, ia5, ia6, ia7; - uint32_t i1, i2, i3, i4, i5, i6, i7, i8; - uint32_t id; - uint32_t n1, n2, j; - - float32_t r1, r2, r3, r4, r5, r6, r7, r8; - float32_t t1, t2; - float32_t s1, s2, s3, s4, s5, s6, s7, s8; - float32_t p1, p2, p3, p4; - float32_t co2, co3, co4, co5, co6, co7, co8; - float32_t si2, si3, si4, si5, si6, si7, si8; - const float32_t C81 = 0.70710678118f; - - n2 = fftLen; - - do - { - n1 = n2; - n2 = n2 >> 3; - i1 = 0; - - do - { - i2 = i1 + n2; - i3 = i2 + n2; - i4 = i3 + n2; - i5 = i4 + n2; - i6 = i5 + n2; - i7 = i6 + n2; - i8 = i7 + n2; - r1 = pSrc[2 * i1] + pSrc[2 * i5]; - r5 = pSrc[2 * i1] - pSrc[2 * i5]; - r2 = pSrc[2 * i2] + pSrc[2 * i6]; - r6 = pSrc[2 * i2] - pSrc[2 * i6]; - r3 = pSrc[2 * i3] + pSrc[2 * i7]; - r7 = pSrc[2 * i3] - pSrc[2 * i7]; - r4 = pSrc[2 * i4] + pSrc[2 * i8]; - r8 = pSrc[2 * i4] - pSrc[2 * i8]; - t1 = r1 - r3; - r1 = r1 + r3; - r3 = r2 - r4; - r2 = r2 + r4; - pSrc[2 * i1] = r1 + r2; - pSrc[2 * i5] = r1 - r2; - r1 = pSrc[2 * i1 + 1] + pSrc[2 * i5 + 1]; - s5 = pSrc[2 * i1 + 1] - pSrc[2 * i5 + 1]; - r2 = pSrc[2 * i2 + 1] + pSrc[2 * i6 + 1]; - s6 = pSrc[2 * i2 + 1] - pSrc[2 * i6 + 1]; - s3 = pSrc[2 * i3 + 1] + pSrc[2 * i7 + 1]; - s7 = pSrc[2 * i3 + 1] - pSrc[2 * i7 + 1]; - r4 = pSrc[2 * i4 + 1] + pSrc[2 * i8 + 1]; - s8 = pSrc[2 * i4 + 1] - pSrc[2 * i8 + 1]; - t2 = r1 - s3; - r1 = r1 + s3; - s3 = r2 - r4; - r2 = r2 + r4; - pSrc[2 * i1 + 1] = r1 + r2; - pSrc[2 * i5 + 1] = r1 - r2; - pSrc[2 * i3] = t1 + s3; - pSrc[2 * i7] = t1 - s3; - pSrc[2 * i3 + 1] = t2 - r3; - pSrc[2 * i7 + 1] = t2 + r3; - r1 = (r6 - r8) * C81; - r6 = (r6 + r8) * C81; - r2 = (s6 - s8) * C81; - s6 = (s6 + s8) * C81; - t1 = r5 - r1; - r5 = r5 + r1; - r8 = r7 - r6; - r7 = r7 + r6; - t2 = s5 - r2; - s5 = s5 + r2; - s8 = s7 - s6; - s7 = s7 + s6; - pSrc[2 * i2] = r5 + s7; - pSrc[2 * i8] = r5 - s7; - pSrc[2 * i6] = t1 + s8; - pSrc[2 * i4] = t1 - s8; - pSrc[2 * i2 + 1] = s5 - r7; - pSrc[2 * i8 + 1] = s5 + r7; - pSrc[2 * i6 + 1] = t2 - r8; - pSrc[2 * i4 + 1] = t2 + r8; - - i1 += n1; - } while(i1 < fftLen); - - if(n2 < 8) - break; - - ia1 = 0; - j = 1; - - do - { - /* index calculation for the coefficients */ - id = ia1 + twidCoefModifier; - ia1 = id; - ia2 = ia1 + id; - ia3 = ia2 + id; - ia4 = ia3 + id; - ia5 = ia4 + id; - ia6 = ia5 + id; - ia7 = ia6 + id; - - co2 = pCoef[2 * ia1]; - co3 = pCoef[2 * ia2]; - co4 = pCoef[2 * ia3]; - co5 = pCoef[2 * ia4]; - co6 = pCoef[2 * ia5]; - co7 = pCoef[2 * ia6]; - co8 = pCoef[2 * ia7]; - si2 = pCoef[2 * ia1 + 1]; - si3 = pCoef[2 * ia2 + 1]; - si4 = pCoef[2 * ia3 + 1]; - si5 = pCoef[2 * ia4 + 1]; - si6 = pCoef[2 * ia5 + 1]; - si7 = pCoef[2 * ia6 + 1]; - si8 = pCoef[2 * ia7 + 1]; - - i1 = j; - - do - { - /* index calculation for the input */ - i2 = i1 + n2; - i3 = i2 + n2; - i4 = i3 + n2; - i5 = i4 + n2; - i6 = i5 + n2; - i7 = i6 + n2; - i8 = i7 + n2; - r1 = pSrc[2 * i1] + pSrc[2 * i5]; - r5 = pSrc[2 * i1] - pSrc[2 * i5]; - r2 = pSrc[2 * i2] + pSrc[2 * i6]; - r6 = pSrc[2 * i2] - pSrc[2 * i6]; - r3 = pSrc[2 * i3] + pSrc[2 * i7]; - r7 = pSrc[2 * i3] - pSrc[2 * i7]; - r4 = pSrc[2 * i4] + pSrc[2 * i8]; - r8 = pSrc[2 * i4] - pSrc[2 * i8]; - t1 = r1 - r3; - r1 = r1 + r3; - r3 = r2 - r4; - r2 = r2 + r4; - pSrc[2 * i1] = r1 + r2; - r2 = r1 - r2; - s1 = pSrc[2 * i1 + 1] + pSrc[2 * i5 + 1]; - s5 = pSrc[2 * i1 + 1] - pSrc[2 * i5 + 1]; - s2 = pSrc[2 * i2 + 1] + pSrc[2 * i6 + 1]; - s6 = pSrc[2 * i2 + 1] - pSrc[2 * i6 + 1]; - s3 = pSrc[2 * i3 + 1] + pSrc[2 * i7 + 1]; - s7 = pSrc[2 * i3 + 1] - pSrc[2 * i7 + 1]; - s4 = pSrc[2 * i4 + 1] + pSrc[2 * i8 + 1]; - s8 = pSrc[2 * i4 + 1] - pSrc[2 * i8 + 1]; - t2 = s1 - s3; - s1 = s1 + s3; - s3 = s2 - s4; - s2 = s2 + s4; - r1 = t1 + s3; - t1 = t1 - s3; - pSrc[2 * i1 + 1] = s1 + s2; - s2 = s1 - s2; - s1 = t2 - r3; - t2 = t2 + r3; - p1 = co5 * r2; - p2 = si5 * s2; - p3 = co5 * s2; - p4 = si5 * r2; - pSrc[2 * i5] = p1 + p2; - pSrc[2 * i5 + 1] = p3 - p4; - p1 = co3 * r1; - p2 = si3 * s1; - p3 = co3 * s1; - p4 = si3 * r1; - pSrc[2 * i3] = p1 + p2; - pSrc[2 * i3 + 1] = p3 - p4; - p1 = co7 * t1; - p2 = si7 * t2; - p3 = co7 * t2; - p4 = si7 * t1; - pSrc[2 * i7] = p1 + p2; - pSrc[2 * i7 + 1] = p3 - p4; - r1 = (r6 - r8) * C81; - r6 = (r6 + r8) * C81; - s1 = (s6 - s8) * C81; - s6 = (s6 + s8) * C81; - t1 = r5 - r1; - r5 = r5 + r1; - r8 = r7 - r6; - r7 = r7 + r6; - t2 = s5 - s1; - s5 = s5 + s1; - s8 = s7 - s6; - s7 = s7 + s6; - r1 = r5 + s7; - r5 = r5 - s7; - r6 = t1 + s8; - t1 = t1 - s8; - s1 = s5 - r7; - s5 = s5 + r7; - s6 = t2 - r8; - t2 = t2 + r8; - p1 = co2 * r1; - p2 = si2 * s1; - p3 = co2 * s1; - p4 = si2 * r1; - pSrc[2 * i2] = p1 + p2; - pSrc[2 * i2 + 1] = p3 - p4; - p1 = co8 * r5; - p2 = si8 * s5; - p3 = co8 * s5; - p4 = si8 * r5; - pSrc[2 * i8] = p1 + p2; - pSrc[2 * i8 + 1] = p3 - p4; - p1 = co6 * r6; - p2 = si6 * s6; - p3 = co6 * s6; - p4 = si6 * r6; - pSrc[2 * i6] = p1 + p2; - pSrc[2 * i6 + 1] = p3 - p4; - p1 = co4 * t1; - p2 = si4 * t2; - p3 = co4 * t2; - p4 = si4 * t1; - pSrc[2 * i4] = p1 + p2; - pSrc[2 * i4 + 1] = p3 - p4; - - i1 += n1; - } while(i1 < fftLen); - - j++; - } while(j < n2); - - twidCoefModifier <<= 3; - } while(n2 > 7); -} - -/** -* @} end of Radix8_CFFT_CIFFT group -*/ |