From 6ccde536191676f9b504055b16c68786858b693d Mon Sep 17 00:00:00 2001
From: "Daniel M. Pelt" <D.M.Pelt@cwi.nl>
Date: Fri, 22 Apr 2016 14:22:53 +0200
Subject: Change CPU FFT implementation
---
include/astra/Fourier.h | 132 +-
src/FilteredBackProjectionAlgorithm.cpp | 45 +-
src/Fourier.cpp | 3514 +++++++++++++++++++++++++++++--
3 files changed, 3382 insertions(+), 309 deletions(-)
diff --git a/include/astra/Fourier.h b/include/astra/Fourier.h
index b515dc6..ff26f82 100644
--- a/include/astra/Fourier.h
+++ b/include/astra/Fourier.h
@@ -33,94 +33,50 @@ $Id$
namespace astra {
-
-/**
- * Perform a 1D DFT or inverse DFT.
- *
- * @param iLength number of elements
- * @param pfRealIn real part of input
- * @param pfImaginaryIn imaginary part of input
- * @param pfRealOut real part of output
- * @param pfImaginaryOut imaginary part of output
- * @param iStrideIn distance between elements in pf*In
- * @param iStrideOut distance between elements in pf*Out
- * @param bInverse if true, perform an inverse DFT
- */
-
-void _AstraExport discreteFourierTransform1D(unsigned int iLength,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- unsigned int iStrideIn,
- unsigned int iStrideOut,
- bool bInverse);
-
-/**
- * Perform a 2D DFT or inverse DFT.
- *
- * @param iHeight number of rows
- * @param iWidth number of columns
- * @param pfRealIn real part of input
- * @param pfImaginaryIn imaginary part of input
- * @param pfRealOut real part of output
- * @param pfImaginaryOut imaginary part of output
- * @param bInverse if true, perform an inverse DFT
- */
-
-void _AstraExport discreteFourierTransform2D(unsigned int iHeight, unsigned int iWidth,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- bool bInverse);
-
-/**
- * Perform a 1D FFT or inverse FFT. The size must be a power of two.
- * This transform can be done in-place, so the input and output pointers
- * may point to the same data.
- *
- * @param iLength number of elements, must be a power of two
- * @param pfRealIn real part of input
- * @param pfImaginaryIn imaginary part of input
- * @param pfRealOut real part of output
- * @param pfImaginaryOut imaginary part of output
- * @param iStrideIn distance between elements in pf*In
- * @param iStrideOut distance between elements in pf*Out
- * @param bInverse if true, perform an inverse DFT
- */
-
-void _AstraExport fastTwoPowerFourierTransform1D(unsigned int iLength,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- unsigned int iStrideIn,
- unsigned int iStrideOut,
- bool bInverse);
-
-/**
- * Perform a 2D FFT or inverse FFT. The size must be a power of two.
- * This transform can be done in-place, so the input and output pointers
- * may point to the same data.
- *
- * @param iHeight number of rows, must be a power of two
- * @param iWidth number of columns, must be a power of two
- * @param pfRealIn real part of input
- * @param pfImaginaryIn imaginary part of input
- * @param pfRealOut real part of output
- * @param pfImaginaryOut imaginary part of output
- * @param bInverse if true, perform an inverse DFT
- */
-
-void _AstraExport fastTwoPowerFourierTransform2D(unsigned int iHeight,
- unsigned int iWidth,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- bool bInverse);
-
+/*
+-------- Complex DFT (Discrete Fourier Transform) --------
+ [definition]
+ <case1>
+ X[k] = sum_j=0^n-1 x[j]*exp(2*pi*i*j*k/n), 0<=k<n
+ <case2>
+ X[k] = sum_j=0^n-1 x[j]*exp(-2*pi*i*j*k/n), 0<=k<n
+ (notes: sum_j=0^n-1 is a summation from j=0 to n-1)
+ [usage]
+ <case1>
+ ip[0] = 0; // first time only
+ cdft(2*n, 1, a, ip, w);
+ <case2>
+ ip[0] = 0; // first time only
+ cdft(2*n, -1, a, ip, w);
+ [parameters]
+ 2*n :data length (int)
+ n >= 1, n = power of 2
+ a[0...2*n-1] :input/output data (float32 *)
+ input data
+ a[2*j] = Re(x[j]),
+ a[2*j+1] = Im(x[j]), 0<=j<n
+ output data
+ a[2*k] = Re(X[k]),
+ a[2*k+1] = Im(X[k]), 0<=k<n
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n/2-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ cdft(2*n, -1, a, ip, w);
+ is
+ cdft(2*n, 1, a, ip, w);
+ for (j = 0; j <= 2 * n - 1; j++) {
+ a[j] *= 1.0 / n;
+ }
+ .
+*/
+void cdft(int n, int isgn, float32 *a, int *ip, float32 *w);
}
diff --git a/src/FilteredBackProjectionAlgorithm.cpp b/src/FilteredBackProjectionAlgorithm.cpp
index ccbfec6..90efd52 100644
--- a/src/FilteredBackProjectionAlgorithm.cpp
+++ b/src/FilteredBackProjectionAlgorithm.cpp
@@ -274,60 +274,57 @@ void CFilteredBackProjectionAlgorithm::performFiltering(CFloat32ProjectionData2D
filter[iDetector] = (2.0f * (zpDetector - iDetector)) / zpDetector;
- float32* pfRe = new float32[iAngleCount * zpDetector];
- float32* pfIm = new float32[iAngleCount * zpDetector];
+ float32* pf = new float32[2 * iAngleCount * zpDetector];
+ int *ip = new int[int(2+sqrt(zpDetector)+1)];
+ ip[0]=0;
+ float32 *w = new float32[zpDetector/2];
// Copy and zero-pad data
for (int iAngle = 0; iAngle < iAngleCount; ++iAngle) {
- float32* pfReRow = pfRe + iAngle * zpDetector;
- float32* pfImRow = pfIm + iAngle * zpDetector;
+ float32* pfRow = pf + iAngle * 2 * zpDetector;
float32* pfDataRow = _pFilteredSinogram->getData() + iAngle * iDetectorCount;
for (int iDetector = 0; iDetector < iDetectorCount; ++iDetector) {
- pfReRow[iDetector] = pfDataRow[iDetector];
- pfImRow[iDetector] = 0.0f;
+ pfRow[2*iDetector] = pfDataRow[iDetector];
+ pfRow[2*iDetector+1] = 0.0f;
}
for (int iDetector = iDetectorCount; iDetector < zpDetector; ++iDetector) {
- pfReRow[iDetector] = 0.0f;
- pfImRow[iDetector] = 0.0f;
+ pfRow[2*iDetector] = 0.0f;
+ pfRow[2*iDetector+1] = 0.0f;
}
}
// in-place FFT
for (int iAngle = 0; iAngle < iAngleCount; ++iAngle) {
- float32* pfReRow = pfRe + iAngle * zpDetector;
- float32* pfImRow = pfIm + iAngle * zpDetector;
-
- fastTwoPowerFourierTransform1D(zpDetector, pfReRow, pfImRow, pfReRow, pfImRow, 1, 1, false);
+ float32* pfRow = pf + iAngle * 2 * zpDetector;
+ cdft(2*zpDetector, -1, pfRow, ip, w);
}
// Filter
for (int iAngle = 0; iAngle < iAngleCount; ++iAngle) {
- float32* pfReRow = pfRe + iAngle * zpDetector;
- float32* pfImRow = pfIm + iAngle * zpDetector;
+ float32* pfRow = pf + iAngle * 2 * zpDetector;
for (int iDetector = 0; iDetector < zpDetector; ++iDetector) {
- pfReRow[iDetector] *= filter[iDetector];
- pfImRow[iDetector] *= filter[iDetector];
+ pfRow[2*iDetector] *= filter[iDetector];
+ pfRow[2*iDetector+1] *= filter[iDetector];
}
}
// in-place inverse FFT
for (int iAngle = 0; iAngle < iAngleCount; ++iAngle) {
- float32* pfReRow = pfRe + iAngle * zpDetector;
- float32* pfImRow = pfIm + iAngle * zpDetector;
-
- fastTwoPowerFourierTransform1D(zpDetector, pfReRow, pfImRow, pfReRow, pfImRow, 1, 1, true);
+ float32* pfRow = pf + iAngle * 2 * zpDetector;
+ cdft(2*zpDetector, 1, pfRow, ip, w);
}
// Copy data back
for (int iAngle = 0; iAngle < iAngleCount; ++iAngle) {
- float32* pfReRow = pfRe + iAngle * zpDetector;
+ float32* pfRow = pf + iAngle * 2 * zpDetector;
float32* pfDataRow = _pFilteredSinogram->getData() + iAngle * iDetectorCount;
for (int iDetector = 0; iDetector < iDetectorCount; ++iDetector)
- pfDataRow[iDetector] = pfReRow[iDetector];
+ pfDataRow[iDetector] = pfRow[2*iDetector] / zpDetector;
}
- delete[] pfRe;
- delete[] pfIm;
+ delete[] pf;
+ delete[] w;
+ delete[] ip;
delete[] filter;
}
diff --git a/src/Fourier.cpp b/src/Fourier.cpp
index 584b633..5ca22e6 100644
--- a/src/Fourier.cpp
+++ b/src/Fourier.cpp
@@ -30,204 +30,3324 @@ $Id$
namespace astra {
+ /*
+Copyright Takuya OOURA, 1996-2001
-void discreteFourierTransform1D(unsigned int iLength,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- unsigned int iStrideIn,
- unsigned int iStrideOut,
- bool inverse)
-{
- for (unsigned int w = 0; w < iLength; w++)
- {
- pfRealOut[iStrideOut*w] = pfImaginaryOut[iStrideOut*w] = 0;
- for (unsigned int y = 0; y < iLength; y++)
- {
- float32 a = 2 * PI * w * y / float32(iLength);
- if (!inverse)
- a = -a;
- float32 ca = cos(a);
- float32 sa = sin(a);
- pfRealOut[iStrideOut*w] += pfRealIn[iStrideIn*y] * ca - pfImaginaryIn[iStrideIn*y] * sa;
- pfImaginaryOut[iStrideOut*w] += pfRealIn[iStrideIn*y] * sa + pfImaginaryIn[iStrideIn*y] * ca;
- }
- }
-
- if (inverse) {
- for (unsigned int x = 0; x < iLength; ++x) {
- pfRealOut[iStrideOut*x] /= iLength;
- pfImaginaryOut[iStrideOut*x] /= iLength;
- }
- }
-}
-
-void discreteFourierTransform2D(unsigned int iHeight, unsigned int iWidth,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- bool inverse)
-{
- float32* reTemp = new float32[iWidth * iHeight];
- float32* imTemp = new float32[iWidth * iHeight];
-
- //calculate the fourier transform of the columns
- for (unsigned int x = 0; x < iWidth; x++)
- {
- discreteFourierTransform1D(iHeight, pfRealIn+x, pfImaginaryIn+x,
- reTemp+x, imTemp+x,
- iWidth, iWidth, inverse);
- }
-
- //calculate the fourier transform of the rows
- for(unsigned int y = 0; y < iHeight; y++)
- {
- discreteFourierTransform1D(iWidth,
- reTemp+y*iWidth,
- imTemp+y*iWidth,
- pfRealOut+y*iWidth,
- pfImaginaryOut+y*iWidth,
- 1, 1, inverse);
- }
-
- delete[] reTemp;
- delete[] imTemp;
-}
-
-/** permute the entries from pfDataIn into pfDataOut to prepare for an
- * in-place FFT. pfDataIn may be equal to pfDataOut.
- */
-static void bitReverse(unsigned int iLength,
- const float32* pfDataIn, float32* pfDataOut,
- unsigned int iStrideShiftIn,
- unsigned int iStrideShiftOut)
-{
- if (pfDataIn == pfDataOut) {
- assert(iStrideShiftIn == iStrideShiftOut);
- float32 t;
- unsigned int j = 0;
- for(unsigned int i = 0; i < iLength - 1; i++) {
- if (i < j) {
- t = pfDataOut[i<<iStrideShiftOut];
- pfDataOut[i<<iStrideShiftOut] = pfDataOut[j<<iStrideShiftOut];
- pfDataOut[j<<iStrideShiftOut] = t;
- }
- unsigned int k = iLength / 2;
- while (k <= j) {
- j -= k;
- k /= 2;
- }
- j += k;
- }
- } else {
- unsigned int j = 0;
- for(unsigned int i = 0; i < iLength - 1; i++) {
- pfDataOut[i<<iStrideShiftOut] = pfDataIn[j<<iStrideShiftIn];
- unsigned int k = iLength / 2;
- while (k <= j) {
- j -= k;
- k /= 2;
- }
- j += k;
- }
- pfDataOut[(iLength-1)<<iStrideShiftOut] = pfDataIn[(iLength-1)<<iStrideShiftOut];
- }
-}
-
-static unsigned int log2(unsigned int n)
-{
- unsigned int l = 0;
- while (n > 1) {
- n /= 2;
- ++l;
- }
- return l;
-}
-
-/** perform 1D FFT. iLength, iStrideIn, iStrideOut must be powers of two. */
-void fastTwoPowerFourierTransform1D(unsigned int iLength,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- unsigned int iStrideIn,
- unsigned int iStrideOut,
- bool inverse)
-{
- unsigned int iStrideShiftIn = log2(iStrideIn);
- unsigned int iStrideShiftOut = log2(iStrideOut);
- unsigned int iLogLength = log2(iLength);
-
- bitReverse(iLength, pfRealIn, pfRealOut, iStrideShiftIn, iStrideShiftOut);
- bitReverse(iLength, pfImaginaryIn, pfImaginaryOut, iStrideShiftIn, iStrideShiftOut);
-
- float32 ca = -1.0;
- float32 sa = 0.0;
- unsigned int l1 = 1, l2 = 1;
- for(unsigned int l=0; l < iLogLength; ++l)
- {
- l1 = l2;
- l2 *= 2;
- float32 u1 = 1.0;
- float32 u2 = 0.0;
- for(unsigned int j = 0; j < l1; j++)
- {
- for(unsigned int i = j; i < iLength; i += l2)
- {
- unsigned int i1 = i + l1;
- float32 t1 = u1 * pfRealOut[i1<<iStrideShiftOut] - u2 * pfImaginaryOut[i1<<iStrideShiftOut];
- float32 t2 = u1 * pfImaginaryOut[i1<<iStrideShiftOut] + u2 * pfRealOut[i1<<iStrideShiftOut];
- pfRealOut[i1<<iStrideShiftOut] = pfRealOut[i<<iStrideShiftOut] - t1;
- pfImaginaryOut[i1<<iStrideShiftOut] = pfImaginaryOut[i<<iStrideShiftOut] - t2;
- pfRealOut[i<<iStrideShiftOut] += t1;
- pfImaginaryOut[i<<iStrideShiftOut] += t2;
- }
- float32 z = u1 * ca - u2 * sa;
- u2 = u1 * sa + u2 * ca;
- u1 = z;
- }
- sa = sqrt((1.0 - ca) / 2.0);
- if (!inverse)
- sa = -sa;
- ca = sqrt((1.0 + ca) / 2.0);
- }
-
- if (inverse) {
- for (unsigned int i = 0; i < iLength; ++i) {
- pfRealOut[i<<iStrideShiftOut] /= iLength;
- pfImaginaryOut[i<<iStrideShiftOut] /= iLength;
- }
- }
-}
-
-void fastTwoPowerFourierTransform2D(unsigned int iHeight,
- unsigned int iWidth,
- const float32* pfRealIn,
- const float32* pfImaginaryIn,
- float32* pfRealOut,
- float32* pfImaginaryOut,
- bool inverse)
-{
- //calculate the fourier transform of the columns
- for (unsigned int x = 0; x < iWidth; x++)
- {
- fastTwoPowerFourierTransform1D(iHeight, pfRealIn+x, pfImaginaryIn+x,
- pfRealOut+x, pfImaginaryOut+x,
- iWidth, iWidth, inverse);
- }
-
- //calculate the fourier transform of the rows
- for (unsigned int y = 0; y < iHeight; y++)
- {
- fastTwoPowerFourierTransform1D(iWidth,
- pfRealOut+y*iWidth,
- pfImaginaryOut+y*iWidth,
- pfRealOut+y*iWidth,
- pfImaginaryOut+y*iWidth,
- 1, 1, inverse);
- }
+You may use, copy, modify and distribute this code for any purpose (include commercial use) and without fee.
+
+Source: http://www.kurims.kyoto-u.ac.jp/~ooura/fft.html
+
+Fast Fourier/Cosine/Sine Transform
+ dimension :one
+ data length :power of 2
+ decimation :frequency
+ radix :split-radix
+ data :inplace
+ table :use
+functions
+ cdft: Complex Discrete Fourier Transform
+ rdft: Real Discrete Fourier Transform
+ ddct: Discrete Cosine Transform
+ ddst: Discrete Sine Transform
+ dfct: Cosine Transform of RDFT (Real Symmetric DFT)
+ dfst: Sine Transform of RDFT (Real Anti-symmetric DFT)
+function prototypes
+ void cdft(int, int, float32 *, int *, float32 *);
+ void rdft(int, int, float32 *, int *, float32 *);
+ void ddct(int, int, float32 *, int *, float32 *);
+ void ddst(int, int, float32 *, int *, float32 *);
+ void dfct(int, float32 *, float32 *, int *, float32 *);
+ void dfst(int, float32 *, float32 *, int *, float32 *);
+macro definitions
+ USE_CDFT_PTHREADS : default=not defined
+ CDFT_THREADS_BEGIN_N : must be >= 512, default=8192
+ CDFT_4THREADS_BEGIN_N : must be >= 512, default=65536
+ USE_CDFT_WINTHREADS : default=not defined
+ CDFT_THREADS_BEGIN_N : must be >= 512, default=32768
+ CDFT_4THREADS_BEGIN_N : must be >= 512, default=524288
+
+
+-------- Complex DFT (Discrete Fourier Transform) --------
+ [definition]
+ <case1>
+ X[k] = sum_j=0^n-1 x[j]*exp(2*pi*i*j*k/n), 0<=k<n
+ <case2>
+ X[k] = sum_j=0^n-1 x[j]*exp(-2*pi*i*j*k/n), 0<=k<n
+ (notes: sum_j=0^n-1 is a summation from j=0 to n-1)
+ [usage]
+ <case1>
+ ip[0] = 0; // first time only
+ cdft(2*n, 1, a, ip, w);
+ <case2>
+ ip[0] = 0; // first time only
+ cdft(2*n, -1, a, ip, w);
+ [parameters]
+ 2*n :data length (int)
+ n >= 1, n = power of 2
+ a[0...2*n-1] :input/output data (float32 *)
+ input data
+ a[2*j] = Re(x[j]),
+ a[2*j+1] = Im(x[j]), 0<=j<n
+ output data
+ a[2*k] = Re(X[k]),
+ a[2*k+1] = Im(X[k]), 0<=k<n
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n/2-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ cdft(2*n, -1, a, ip, w);
+ is
+ cdft(2*n, 1, a, ip, w);
+ for (j = 0; j <= 2 * n - 1; j++) {
+ a[j] *= 1.0 / n;
+ }
+ .
+
+
+-------- Real DFT / Inverse of Real DFT --------
+ [definition]
+ <case1> RDFT
+ R[k] = sum_j=0^n-1 a[j]*cos(2*pi*j*k/n), 0<=k<=n/2
+ I[k] = sum_j=0^n-1 a[j]*sin(2*pi*j*k/n), 0<k<n/2
+ <case2> IRDFT (excluding scale)
+ a[k] = (R[0] + R[n/2]*cos(pi*k))/2 +
+ sum_j=1^n/2-1 R[j]*cos(2*pi*j*k/n) +
+ sum_j=1^n/2-1 I[j]*sin(2*pi*j*k/n), 0<=k<n
+ [usage]
+ <case1>
+ ip[0] = 0; // first time only
+ rdft(n, 1, a, ip, w);
+ <case2>
+ ip[0] = 0; // first time only
+ rdft(n, -1, a, ip, w);
+ [parameters]
+ n :data length (int)
+ n >= 2, n = power of 2
+ a[0...n-1] :input/output data (float32 *)
+ <case1>
+ output data
+ a[2*k] = R[k], 0<=k<n/2
+ a[2*k+1] = I[k], 0<k<n/2
+ a[1] = R[n/2]
+ <case2>
+ input data
+ a[2*j] = R[j], 0<=j<n/2
+ a[2*j+1] = I[j], 0<j<n/2
+ a[1] = R[n/2]
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n/2)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n/2+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n/2-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ rdft(n, 1, a, ip, w);
+ is
+ rdft(n, -1, a, ip, w);
+ for (j = 0; j <= n - 1; j++) {
+ a[j] *= 2.0 / n;
+ }
+ .
+
+
+-------- DCT (Discrete Cosine Transform) / Inverse of DCT --------
+ [definition]
+ <case1> IDCT (excluding scale)
+ C[k] = sum_j=0^n-1 a[j]*cos(pi*j*(k+1/2)/n), 0<=k<n
+ <case2> DCT
+ C[k] = sum_j=0^n-1 a[j]*cos(pi*(j+1/2)*k/n), 0<=k<n
+ [usage]
+ <case1>
+ ip[0] = 0; // first time only
+ ddct(n, 1, a, ip, w);
+ <case2>
+ ip[0] = 0; // first time only
+ ddct(n, -1, a, ip, w);
+ [parameters]
+ n :data length (int)
+ n >= 2, n = power of 2
+ a[0...n-1] :input/output data (float32 *)
+ output data
+ a[k] = C[k], 0<=k<n
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n/2)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n/2+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n*5/4-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ ddct(n, -1, a, ip, w);
+ is
+ a[0] *= 0.5;
+ ddct(n, 1, a, ip, w);
+ for (j = 0; j <= n - 1; j++) {
+ a[j] *= 2.0 / n;
+ }
+ .
+
+
+-------- DST (Discrete Sine Transform) / Inverse of DST --------
+ [definition]
+ <case1> IDST (excluding scale)
+ S[k] = sum_j=1^n A[j]*sin(pi*j*(k+1/2)/n), 0<=k<n
+ <case2> DST
+ S[k] = sum_j=0^n-1 a[j]*sin(pi*(j+1/2)*k/n), 0<k<=n
+ [usage]
+ <case1>
+ ip[0] = 0; // first time only
+ ddst(n, 1, a, ip, w);
+ <case2>
+ ip[0] = 0; // first time only
+ ddst(n, -1, a, ip, w);
+ [parameters]
+ n :data length (int)
+ n >= 2, n = power of 2
+ a[0...n-1] :input/output data (float32 *)
+ <case1>
+ input data
+ a[j] = A[j], 0<j<n
+ a[0] = A[n]
+ output data
+ a[k] = S[k], 0<=k<n
+ <case2>
+ output data
+ a[k] = S[k], 0<k<n
+ a[0] = S[n]
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n/2)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n/2+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n*5/4-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ ddst(n, -1, a, ip, w);
+ is
+ a[0] *= 0.5;
+ ddst(n, 1, a, ip, w);
+ for (j = 0; j <= n - 1; j++) {
+ a[j] *= 2.0 / n;
+ }
+ .
+
+
+-------- Cosine Transform of RDFT (Real Symmetric DFT) --------
+ [definition]
+ C[k] = sum_j=0^n a[j]*cos(pi*j*k/n), 0<=k<=n
+ [usage]
+ ip[0] = 0; // first time only
+ dfct(n, a, t, ip, w);
+ [parameters]
+ n :data length - 1 (int)
+ n >= 2, n = power of 2
+ a[0...n] :input/output data (float32 *)
+ output data
+ a[k] = C[k], 0<=k<=n
+ t[0...n/2] :work area (float32 *)
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n/4)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n/4+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n*5/8-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ a[0] *= 0.5;
+ a[n] *= 0.5;
+ dfct(n, a, t, ip, w);
+ is
+ a[0] *= 0.5;
+ a[n] *= 0.5;
+ dfct(n, a, t, ip, w);
+ for (j = 0; j <= n; j++) {
+ a[j] *= 2.0 / n;
+ }
+ .
+
+
+-------- Sine Transform of RDFT (Real Anti-symmetric DFT) --------
+ [definition]
+ S[k] = sum_j=1^n-1 a[j]*sin(pi*j*k/n), 0<k<n
+ [usage]
+ ip[0] = 0; // first time only
+ dfst(n, a, t, ip, w);
+ [parameters]
+ n :data length + 1 (int)
+ n >= 2, n = power of 2
+ a[0...n-1] :input/output data (float32 *)
+ output data
+ a[k] = S[k], 0<k<n
+ (a[0] is used for work area)
+ t[0...n/2-1] :work area (float32 *)
+ ip[0...*] :work area for bit reversal (int *)
+ length of ip >= 2+sqrt(n/4)
+ strictly,
+ length of ip >=
+ 2+(1<<(int)(log(n/4+0.5)/log(2))/2).
+ ip[0],ip[1] are pointers of the cos/sin table.
+ w[0...n*5/8-1] :cos/sin table (float32 *)
+ w[],ip[] are initialized if ip[0] == 0.
+ [remark]
+ Inverse of
+ dfst(n, a, t, ip, w);
+ is
+ dfst(n, a, t, ip, w);
+ for (j = 1; j <= n - 1; j++) {
+ a[j] *= 2.0 / n;
+ }
+ .
+
+
+Appendix :
+ The cos/sin table is recalculated when the larger table required.
+ w[] and ip[] are compatible with all routines.
+*/
+
+
+void cdft(int n, int isgn, float32 *a, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ int nw;
+
+ nw = ip[0];
+ if (n > (nw << 2)) {
+ nw = n >> 2;
+ makewt(nw, ip, w);
+ }
+ if (isgn >= 0) {
+ cftfsub(n, a, ip, nw, w);
+ } else {
+ cftbsub(n, a, ip, nw, w);
+ }
+}
+
+
+void rdft(int n, int isgn, float32 *a, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void makect(int nc, int *ip, float32 *c);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void rftfsub(int n, float32 *a, int nc, float32 *c);
+ void rftbsub(int n, float32 *a, int nc, float32 *c);
+ int nw, nc;
+ float32 xi;
+
+ nw = ip[0];
+ if (n > (nw << 2)) {
+ nw = n >> 2;
+ makewt(nw, ip, w);
+ }
+ nc = ip[1];
+ if (n > (nc << 2)) {
+ nc = n >> 2;
+ makect(nc, ip, w + nw);
+ }
+ if (isgn >= 0) {
+ if (n > 4) {
+ cftfsub(n, a, ip, nw, w);
+ rftfsub(n, a, nc, w + nw);
+ } else if (n == 4) {
+ cftfsub(n, a, ip, nw, w);
+ }
+ xi = a[0] - a[1];
+ a[0] += a[1];
+ a[1] = xi;
+ } else {
+ a[1] = 0.5 * (a[0] - a[1]);
+ a[0] -= a[1];
+ if (n > 4) {
+ rftbsub(n, a, nc, w + nw);
+ cftbsub(n, a, ip, nw, w);
+ } else if (n == 4) {
+ cftbsub(n, a, ip, nw, w);
+ }
+ }
+}
+
+
+void ddct(int n, int isgn, float32 *a, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void makect(int nc, int *ip, float32 *c);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void rftfsub(int n, float32 *a, int nc, float32 *c);
+ void rftbsub(int n, float32 *a, int nc, float32 *c);
+ void dctsub(int n, float32 *a, int nc, float32 *c);
+ int j, nw, nc;
+ float32 xr;
+
+ nw = ip[0];
+ if (n > (nw << 2)) {
+ nw = n >> 2;
+ makewt(nw, ip, w);
+ }
+ nc = ip[1];
+ if (n > nc) {
+ nc = n;
+ makect(nc, ip, w + nw);
+ }
+ if (isgn < 0) {
+ xr = a[n - 1];
+ for (j = n - 2; j >= 2; j -= 2) {
+ a[j + 1] = a[j] - a[j - 1];
+ a[j] += a[j - 1];
+ }
+ a[1] = a[0] - xr;
+ a[0] += xr;
+ if (n > 4) {
+ rftbsub(n, a, nc, w + nw);
+ cftbsub(n, a, ip, nw, w);
+ } else if (n == 4) {
+ cftbsub(n, a, ip, nw, w);
+ }
+ }
+ dctsub(n, a, nc, w + nw);
+ if (isgn >= 0) {
+ if (n > 4) {
+ cftfsub(n, a, ip, nw, w);
+ rftfsub(n, a, nc, w + nw);
+ } else if (n == 4) {
+ cftfsub(n, a, ip, nw, w);
+ }
+ xr = a[0] - a[1];
+ a[0] += a[1];
+ for (j = 2; j < n; j += 2) {
+ a[j - 1] = a[j] - a[j + 1];
+ a[j] += a[j + 1];
+ }
+ a[n - 1] = xr;
+ }
+}
+
+
+void ddst(int n, int isgn, float32 *a, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void makect(int nc, int *ip, float32 *c);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void rftfsub(int n, float32 *a, int nc, float32 *c);
+ void rftbsub(int n, float32 *a, int nc, float32 *c);
+ void dstsub(int n, float32 *a, int nc, float32 *c);
+ int j, nw, nc;
+ float32 xr;
+
+ nw = ip[0];
+ if (n > (nw << 2)) {
+ nw = n >> 2;
+ makewt(nw, ip, w);
+ }
+ nc = ip[1];
+ if (n > nc) {
+ nc = n;
+ makect(nc, ip, w + nw);
+ }
+ if (isgn < 0) {
+ xr = a[n - 1];
+ for (j = n - 2; j >= 2; j -= 2) {
+ a[j + 1] = -a[j] - a[j - 1];
+ a[j] -= a[j - 1];
+ }
+ a[1] = a[0] + xr;
+ a[0] -= xr;
+ if (n > 4) {
+ rftbsub(n, a, nc, w + nw);
+ cftbsub(n, a, ip, nw, w);
+ } else if (n == 4) {
+ cftbsub(n, a, ip, nw, w);
+ }
+ }
+ dstsub(n, a, nc, w + nw);
+ if (isgn >= 0) {
+ if (n > 4) {
+ cftfsub(n, a, ip, nw, w);
+ rftfsub(n, a, nc, w + nw);
+ } else if (n == 4) {
+ cftfsub(n, a, ip, nw, w);
+ }
+ xr = a[0] - a[1];
+ a[0] += a[1];
+ for (j = 2; j < n; j += 2) {
+ a[j - 1] = -a[j] - a[j + 1];
+ a[j] -= a[j + 1];
+ }
+ a[n - 1] = -xr;
+ }
+}
+
+
+void dfct(int n, float32 *a, float32 *t, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void makect(int nc, int *ip, float32 *c);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void rftfsub(int n, float32 *a, int nc, float32 *c);
+ void dctsub(int n, float32 *a, int nc, float32 *c);
+ int j, k, l, m, mh, nw, nc;
+ float32 xr, xi, yr, yi;
+
+ nw = ip[0];
+ if (n > (nw << 3)) {
+ nw = n >> 3;
+ makewt(nw, ip, w);
+ }
+ nc = ip[1];
+ if (n > (nc << 1)) {
+ nc = n >> 1;
+ makect(nc, ip, w + nw);
+ }
+ m = n >> 1;
+ yi = a[m];
+ xi = a[0] + a[n];
+ a[0] -= a[n];
+ t[0] = xi - yi;
+ t[m] = xi + yi;
+ if (n > 2) {
+ mh = m >> 1;
+ for (j = 1; j < mh; j++) {
+ k = m - j;
+ xr = a[j] - a[n - j];
+ xi = a[j] + a[n - j];
+ yr = a[k] - a[n - k];
+ yi = a[k] + a[n - k];
+ a[j] = xr;
+ a[k] = yr;
+ t[j] = xi - yi;
+ t[k] = xi + yi;
+ }
+ t[mh] = a[mh] + a[n - mh];
+ a[mh] -= a[n - mh];
+ dctsub(m, a, nc, w + nw);
+ if (m > 4) {
+ cftfsub(m, a, ip, nw, w);
+ rftfsub(m, a, nc, w + nw);
+ } else if (m == 4) {
+ cftfsub(m, a, ip, nw, w);
+ }
+ a[n - 1] = a[0] - a[1];
+ a[1] = a[0] + a[1];
+ for (j = m - 2; j >= 2; j -= 2) {
+ a[2 * j + 1] = a[j] + a[j + 1];
+ a[2 * j - 1] = a[j] - a[j + 1];
+ }
+ l = 2;
+ m = mh;
+ while (m >= 2) {
+ dctsub(m, t, nc, w + nw);
+ if (m > 4) {
+ cftfsub(m, t, ip, nw, w);
+ rftfsub(m, t, nc, w + nw);
+ } else if (m == 4) {
+ cftfsub(m, t, ip, nw, w);
+ }
+ a[n - l] = t[0] - t[1];
+ a[l] = t[0] + t[1];
+ k = 0;
+ for (j = 2; j < m; j += 2) {
+ k += l << 2;
+ a[k - l] = t[j] - t[j + 1];
+ a[k + l] = t[j] + t[j + 1];
+ }
+ l <<= 1;
+ mh = m >> 1;
+ for (j = 0; j < mh; j++) {
+ k = m - j;
+ t[j] = t[m + k] - t[m + j];
+ t[k] = t[m + k] + t[m + j];
+ }
+ t[mh] = t[m + mh];
+ m = mh;
+ }
+ a[l] = t[0];
+ a[n] = t[2] - t[1];
+ a[0] = t[2] + t[1];
+ } else {
+ a[1] = a[0];
+ a[2] = t[0];
+ a[0] = t[1];
+ }
+}
+
+
+void dfst(int n, float32 *a, float32 *t, int *ip, float32 *w)
+{
+ void makewt(int nw, int *ip, float32 *w);
+ void makect(int nc, int *ip, float32 *c);
+ void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w);
+ void rftfsub(int n, float32 *a, int nc, float32 *c);
+ void dstsub(int n, float32 *a, int nc, float32 *c);
+ int j, k, l, m, mh, nw, nc;
+ float32 xr, xi, yr, yi;
+
+ nw = ip[0];
+ if (n > (nw << 3)) {
+ nw = n >> 3;
+ makewt(nw, ip, w);
+ }
+ nc = ip[1];
+ if (n > (nc << 1)) {
+ nc = n >> 1;
+ makect(nc, ip, w + nw);
+ }
+ if (n > 2) {
+ m = n >> 1;
+ mh = m >> 1;
+ for (j = 1; j < mh; j++) {
+ k = m - j;
+ xr = a[j] + a[n - j];
+ xi = a[j] - a[n - j];
+ yr = a[k] + a[n - k];
+ yi = a[k] - a[n - k];
+ a[j] = xr;
+ a[k] = yr;
+ t[j] = xi + yi;
+ t[k] = xi - yi;
+ }
+ t[0] = a[mh] - a[n - mh];
+ a[mh] += a[n - mh];
+ a[0] = a[m];
+ dstsub(m, a, nc, w + nw);
+ if (m > 4) {
+ cftfsub(m, a, ip, nw, w);
+ rftfsub(m, a, nc, w + nw);
+ } else if (m == 4) {
+ cftfsub(m, a, ip, nw, w);
+ }
+ a[n - 1] = a[1] - a[0];
+ a[1] = a[0] + a[1];
+ for (j = m - 2; j >= 2; j -= 2) {
+ a[2 * j + 1] = a[j] - a[j + 1];
+ a[2 * j - 1] = -a[j] - a[j + 1];
+ }
+ l = 2;
+ m = mh;
+ while (m >= 2) {
+ dstsub(m, t, nc, w + nw);
+ if (m > 4) {
+ cftfsub(m, t, ip, nw, w);
+ rftfsub(m, t, nc, w + nw);
+ } else if (m == 4) {
+ cftfsub(m, t, ip, nw, w);
+ }
+ a[n - l] = t[1] - t[0];
+ a[l] = t[0] + t[1];
+ k = 0;
+ for (j = 2; j < m; j += 2) {
+ k += l << 2;
+ a[k - l] = -t[j] - t[j + 1];
+ a[k + l] = t[j] - t[j + 1];
+ }
+ l <<= 1;
+ mh = m >> 1;
+ for (j = 1; j < mh; j++) {
+ k = m - j;
+ t[j] = t[m + k] + t[m + j];
+ t[k] = t[m + k] - t[m + j];
+ }
+ t[0] = t[m + mh];
+ m = mh;
+ }
+ a[l] = t[0];
+ }
+ a[0] = 0;
+}
+
+
+/* -------- initializing routines -------- */
+
+
+#include <math.h>
+
+void makewt(int nw, int *ip, float32 *w)
+{
+ void makeipt(int nw, int *ip);
+ int j, nwh, nw0, nw1;
+ float32 delta, wn4r, wk1r, wk1i, wk3r, wk3i;
+
+ ip[0] = nw;
+ ip[1] = 1;
+ if (nw > 2) {
+ nwh = nw >> 1;
+ delta = atan(1.0) / nwh;
+ wn4r = cos(delta * nwh);
+ w[0] = 1;
+ w[1] = wn4r;
+ if (nwh == 4) {
+ w[2] = cos(delta * 2);
+ w[3] = sin(delta * 2);
+ } else if (nwh > 4) {
+ makeipt(nw, ip);
+ w[2] = 0.5 / cos(delta * 2);
+ w[3] = 0.5 / cos(delta * 6);
+ for (j = 4; j < nwh; j += 4) {
+ w[j] = cos(delta * j);
+ w[j + 1] = sin(delta * j);
+ w[j + 2] = cos(3 * delta * j);
+ w[j + 3] = -sin(3 * delta * j);
+ }
+ }
+ nw0 = 0;
+ while (nwh > 2) {
+ nw1 = nw0 + nwh;
+ nwh >>= 1;
+ w[nw1] = 1;
+ w[nw1 + 1] = wn4r;
+ if (nwh == 4) {
+ wk1r = w[nw0 + 4];
+ wk1i = w[nw0 + 5];
+ w[nw1 + 2] = wk1r;
+ w[nw1 + 3] = wk1i;
+ } else if (nwh > 4) {
+ wk1r = w[nw0 + 4];
+ wk3r = w[nw0 + 6];
+ w[nw1 + 2] = 0.5 / wk1r;
+ w[nw1 + 3] = 0.5 / wk3r;
+ for (j = 4; j < nwh; j += 4) {
+ wk1r = w[nw0 + 2 * j];
+ wk1i = w[nw0 + 2 * j + 1];
+ wk3r = w[nw0 + 2 * j + 2];
+ wk3i = w[nw0 + 2 * j + 3];
+ w[nw1 + j] = wk1r;
+ w[nw1 + j + 1] = wk1i;
+ w[nw1 + j + 2] = wk3r;
+ w[nw1 + j + 3] = wk3i;
+ }
+ }
+ nw0 = nw1;
+ }
+ }
+}
+
+
+void makeipt(int nw, int *ip)
+{
+ int j, l, m, m2, p, q;
+
+ ip[2] = 0;
+ ip[3] = 16;
+ m = 2;
+ for (l = nw; l > 32; l >>= 2) {
+ m2 = m << 1;
+ q = m2 << 3;
+ for (j = m; j < m2; j++) {
+ p = ip[j] << 2;
+ ip[m + j] = p;
+ ip[m2 + j] = p + q;
+ }
+ m = m2;
+ }
+}
+
+
+void makect(int nc, int *ip, float32 *c)
+{
+ int j, nch;
+ float32 delta;
+
+ ip[1] = nc;
+ if (nc > 1) {
+ nch = nc >> 1;
+ delta = atan(1.0) / nch;
+ c[0] = cos(delta * nch);
+ c[nch] = 0.5 * c[0];
+ for (j = 1; j < nch; j++) {
+ c[j] = 0.5 * cos(delta * j);
+ c[nc - j] = 0.5 * sin(delta * j);
+ }
+ }
+}
+
+
+/* -------- child routines -------- */
+
+
+#ifdef USE_CDFT_PTHREADS
+#define USE_CDFT_THREADS
+#ifndef CDFT_THREADS_BEGIN_N
+#define CDFT_THREADS_BEGIN_N 8192
+#endif
+#ifndef CDFT_4THREADS_BEGIN_N
+#define CDFT_4THREADS_BEGIN_N 65536
+#endif
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#define cdft_thread_t pthread_t
+#define cdft_thread_create(thp,func,argp) { \
+ if (pthread_create(thp, NULL, func, (void *) argp) != 0) { \
+ fprintf(stderr, "cdft thread error\n"); \
+ exit(1); \
+ } \
+}
+#define cdft_thread_wait(th) { \
+ if (pthread_join(th, NULL) != 0) { \
+ fprintf(stderr, "cdft thread error\n"); \
+ exit(1); \
+ } \
+}
+#endif /* USE_CDFT_PTHREADS */
+
+
+#ifdef USE_CDFT_WINTHREADS
+#define USE_CDFT_THREADS
+#ifndef CDFT_THREADS_BEGIN_N
+#define CDFT_THREADS_BEGIN_N 32768
+#endif
+#ifndef CDFT_4THREADS_BEGIN_N
+#define CDFT_4THREADS_BEGIN_N 524288
+#endif
+#include <windows.h>
+#include <stdio.h>
+#include <stdlib.h>
+#define cdft_thread_t HANDLE
+#define cdft_thread_create(thp,func,argp) { \
+ DWORD thid; \
+ *(thp) = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE) func, (LPVOID) argp, 0, &thid); \
+ if (*(thp) == 0) { \
+ fprintf(stderr, "cdft thread error\n"); \
+ exit(1); \
+ } \
+}
+#define cdft_thread_wait(th) { \
+ WaitForSingleObject(th, INFINITE); \
+ CloseHandle(th); \
+}
+#endif /* USE_CDFT_WINTHREADS */
+
+
+void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w)
+{
+ void bitrv2(int n, int *ip, float32 *a);
+ void bitrv216(float32 *a);
+ void bitrv208(float32 *a);
+ void cftf1st(int n, float32 *a, float32 *w);
+ void cftrec4(int n, float32 *a, int nw, float32 *w);
+ void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w);
+ void cftfx41(int n, float32 *a, int nw, float32 *w);
+ void cftf161(float32 *a, float32 *w);
+ void cftf081(float32 *a, float32 *w);
+ void cftf040(float32 *a);
+ void cftx020(float32 *a);
+#ifdef USE_CDFT_THREADS
+ void cftrec4_th(int n, float32 *a, int nw, float32 *w);
+#endif /* USE_CDFT_THREADS */
+
+ if (n > 8) {
+ if (n > 32) {
+ cftf1st(n, a, &w[nw - (n >> 2)]);
+#ifdef USE_CDFT_THREADS
+ if (n > CDFT_THREADS_BEGIN_N) {
+ cftrec4_th(n, a, nw, w);
+ } else
+#endif /* USE_CDFT_THREADS */
+ if (n > 512) {
+ cftrec4(n, a, nw, w);
+ } else if (n > 128) {
+ cftleaf(n, 1, a, nw, w);
+ } else {
+ cftfx41(n, a, nw, w);
+ }
+ bitrv2(n, ip, a);
+ } else if (n == 32) {
+ cftf161(a, &w[nw - 8]);
+ bitrv216(a);
+ } else {
+ cftf081(a, w);
+ bitrv208(a);
+ }
+ } else if (n == 8) {
+ cftf040(a);
+ } else if (n == 4) {
+ cftx020(a);
+ }
+}
+
+
+void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w)
+{
+ void bitrv2conj(int n, int *ip, float32 *a);
+ void bitrv216neg(float32 *a);
+ void bitrv208neg(float32 *a);
+ void cftb1st(int n, float32 *a, float32 *w);
+ void cftrec4(int n, float32 *a, int nw, float32 *w);
+ void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w);
+ void cftfx41(int n, float32 *a, int nw, float32 *w);
+ void cftf161(float32 *a, float32 *w);
+ void cftf081(float32 *a, float32 *w);
+ void cftb040(float32 *a);
+ void cftx020(float32 *a);
+#ifdef USE_CDFT_THREADS
+ void cftrec4_th(int n, float32 *a, int nw, float32 *w);
+#endif /* USE_CDFT_THREADS */
+
+ if (n > 8) {
+ if (n > 32) {
+ cftb1st(n, a, &w[nw - (n >> 2)]);
+#ifdef USE_CDFT_THREADS
+ if (n > CDFT_THREADS_BEGIN_N) {
+ cftrec4_th(n, a, nw, w);
+ } else
+#endif /* USE_CDFT_THREADS */
+ if (n > 512) {
+ cftrec4(n, a, nw, w);
+ } else if (n > 128) {
+ cftleaf(n, 1, a, nw, w);
+ } else {
+ cftfx41(n, a, nw, w);
+ }
+ bitrv2conj(n, ip, a);
+ } else if (n == 32) {
+ cftf161(a, &w[nw - 8]);
+ bitrv216neg(a);
+ } else {
+ cftf081(a, w);
+ bitrv208neg(a);
+ }
+ } else if (n == 8) {
+ cftb040(a);
+ } else if (n == 4) {
+ cftx020(a);
+ }
+}
+
+
+void bitrv2(int n, int *ip, float32 *a)
+{
+ int j, j1, k, k1, l, m, nh, nm;
+ float32 xr, xi, yr, yi;
+
+ m = 1;
+ for (l = n >> 2; l > 8; l >>= 2) {
+ m <<= 1;
+ }
+ nh = n >> 1;
+ nm = 4 * m;
+ if (l == 8) {
+ for (k = 0; k < m; k++) {
+ for (j = 0; j < k; j++) {
+ j1 = 4 * j + 2 * ip[m + k];
+ k1 = 4 * k + 2 * ip[m + j];
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh;
+ k1 += 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh;
+ k1 -= 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ k1 = 4 * k + 2 * ip[m + k];
+ j1 = k1 + 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= 2;
+ k1 -= nh;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh + 2;
+ k1 += nh + 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh - nm;
+ k1 += 2 * nm - 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ } else {
+ for (k = 0; k < m; k++) {
+ for (j = 0; j < k; j++) {
+ j1 = 4 * j + ip[m + k];
+ k1 = 4 * k + ip[m + j];
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh;
+ k1 += 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh;
+ k1 -= 2;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ k1 = 4 * k + ip[m + k];
+ j1 = k1 + 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = a[j1 + 1];
+ yr = a[k1];
+ yi = a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ }
+}
+
+
+void bitrv2conj(int n, int *ip, float32 *a)
+{
+ int j, j1, k, k1, l, m, nh, nm;
+ float32 xr, xi, yr, yi;
+
+ m = 1;
+ for (l = n >> 2; l > 8; l >>= 2) {
+ m <<= 1;
+ }
+ nh = n >> 1;
+ nm = 4 * m;
+ if (l == 8) {
+ for (k = 0; k < m; k++) {
+ for (j = 0; j < k; j++) {
+ j1 = 4 * j + 2 * ip[m + k];
+ k1 = 4 * k + 2 * ip[m + j];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh;
+ k1 += 2;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh;
+ k1 -= 2;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ k1 = 4 * k + 2 * ip[m + k];
+ j1 = k1 + 2;
+ k1 += nh;
+ a[j1 - 1] = -a[j1 - 1];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ a[k1 + 3] = -a[k1 + 3];
+ j1 += nm;
+ k1 += 2 * nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= 2;
+ k1 -= nh;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh + 2;
+ k1 += nh + 2;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh - nm;
+ k1 += 2 * nm - 2;
+ a[j1 - 1] = -a[j1 - 1];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ a[k1 + 3] = -a[k1 + 3];
+ }
+ } else {
+ for (k = 0; k < m; k++) {
+ for (j = 0; j < k; j++) {
+ j1 = 4 * j + ip[m + k];
+ k1 = 4 * k + ip[m + j];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nh;
+ k1 += 2;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += 2;
+ k1 += nh;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 += nm;
+ k1 += nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nh;
+ k1 -= 2;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ j1 -= nm;
+ k1 -= nm;
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ }
+ k1 = 4 * k + ip[m + k];
+ j1 = k1 + 2;
+ k1 += nh;
+ a[j1 - 1] = -a[j1 - 1];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ a[k1 + 3] = -a[k1 + 3];
+ j1 += nm;
+ k1 += nm;
+ a[j1 - 1] = -a[j1 - 1];
+ xr = a[j1];
+ xi = -a[j1 + 1];
+ yr = a[k1];
+ yi = -a[k1 + 1];
+ a[j1] = yr;
+ a[j1 + 1] = yi;
+ a[k1] = xr;
+ a[k1 + 1] = xi;
+ a[k1 + 3] = -a[k1 + 3];
+ }
+ }
+}
+
+
+void bitrv216(float32 *a)
+{
+ float32 x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i,
+ x5r, x5i, x7r, x7i, x8r, x8i, x10r, x10i,
+ x11r, x11i, x12r, x12i, x13r, x13i, x14r, x14i;
+
+ x1r = a[2];
+ x1i = a[3];
+ x2r = a[4];
+ x2i = a[5];
+ x3r = a[6];
+ x3i = a[7];
+ x4r = a[8];
+ x4i = a[9];
+ x5r = a[10];
+ x5i = a[11];
+ x7r = a[14];
+ x7i = a[15];
+ x8r = a[16];
+ x8i = a[17];
+ x10r = a[20];
+ x10i = a[21];
+ x11r = a[22];
+ x11i = a[23];
+ x12r = a[24];
+ x12i = a[25];
+ x13r = a[26];
+ x13i = a[27];
+ x14r = a[28];
+ x14i = a[29];
+ a[2] = x8r;
+ a[3] = x8i;
+ a[4] = x4r;
+ a[5] = x4i;
+ a[6] = x12r;
+ a[7] = x12i;
+ a[8] = x2r;
+ a[9] = x2i;
+ a[10] = x10r;
+ a[11] = x10i;
+ a[14] = x14r;
+ a[15] = x14i;
+ a[16] = x1r;
+ a[17] = x1i;
+ a[20] = x5r;
+ a[21] = x5i;
+ a[22] = x13r;
+ a[23] = x13i;
+ a[24] = x3r;
+ a[25] = x3i;
+ a[26] = x11r;
+ a[27] = x11i;
+ a[28] = x7r;
+ a[29] = x7i;
+}
+
+
+void bitrv216neg(float32 *a)
+{
+ float32 x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i,
+ x5r, x5i, x6r, x6i, x7r, x7i, x8r, x8i,
+ x9r, x9i, x10r, x10i, x11r, x11i, x12r, x12i,
+ x13r, x13i, x14r, x14i, x15r, x15i;
+
+ x1r = a[2];
+ x1i = a[3];
+ x2r = a[4];
+ x2i = a[5];
+ x3r = a[6];
+ x3i = a[7];
+ x4r = a[8];
+ x4i = a[9];
+ x5r = a[10];
+ x5i = a[11];
+ x6r = a[12];
+ x6i = a[13];
+ x7r = a[14];
+ x7i = a[15];
+ x8r = a[16];
+ x8i = a[17];
+ x9r = a[18];
+ x9i = a[19];
+ x10r = a[20];
+ x10i = a[21];
+ x11r = a[22];
+ x11i = a[23];
+ x12r = a[24];
+ x12i = a[25];
+ x13r = a[26];
+ x13i = a[27];
+ x14r = a[28];
+ x14i = a[29];
+ x15r = a[30];
+ x15i = a[31];
+ a[2] = x15r;
+ a[3] = x15i;
+ a[4] = x7r;
+ a[5] = x7i;
+ a[6] = x11r;
+ a[7] = x11i;
+ a[8] = x3r;
+ a[9] = x3i;
+ a[10] = x13r;
+ a[11] = x13i;
+ a[12] = x5r;
+ a[13] = x5i;
+ a[14] = x9r;
+ a[15] = x9i;
+ a[16] = x1r;
+ a[17] = x1i;
+ a[18] = x14r;
+ a[19] = x14i;
+ a[20] = x6r;
+ a[21] = x6i;
+ a[22] = x10r;
+ a[23] = x10i;
+ a[24] = x2r;
+ a[25] = x2i;
+ a[26] = x12r;
+ a[27] = x12i;
+ a[28] = x4r;
+ a[29] = x4i;
+ a[30] = x8r;
+ a[31] = x8i;
+}
+
+
+void bitrv208(float32 *a)
+{
+ float32 x1r, x1i, x3r, x3i, x4r, x4i, x6r, x6i;
+
+ x1r = a[2];
+ x1i = a[3];
+ x3r = a[6];
+ x3i = a[7];
+ x4r = a[8];
+ x4i = a[9];
+ x6r = a[12];
+ x6i = a[13];
+ a[2] = x4r;
+ a[3] = x4i;
+ a[6] = x6r;
+ a[7] = x6i;
+ a[8] = x1r;
+ a[9] = x1i;
+ a[12] = x3r;
+ a[13] = x3i;
+}
+
+
+void bitrv208neg(float32 *a)
+{
+ float32 x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i,
+ x5r, x5i, x6r, x6i, x7r, x7i;
+
+ x1r = a[2];
+ x1i = a[3];
+ x2r = a[4];
+ x2i = a[5];
+ x3r = a[6];
+ x3i = a[7];
+ x4r = a[8];
+ x4i = a[9];
+ x5r = a[10];
+ x5i = a[11];
+ x6r = a[12];
+ x6i = a[13];
+ x7r = a[14];
+ x7i = a[15];
+ a[2] = x7r;
+ a[3] = x7i;
+ a[4] = x3r;
+ a[5] = x3i;
+ a[6] = x5r;
+ a[7] = x5i;
+ a[8] = x1r;
+ a[9] = x1i;
+ a[10] = x6r;
+ a[11] = x6i;
+ a[12] = x2r;
+ a[13] = x2i;
+ a[14] = x4r;
+ a[15] = x4i;
+}
+
+
+void cftf1st(int n, float32 *a, float32 *w)
+{
+ int j, j0, j1, j2, j3, k, m, mh;
+ float32 wn4r, csc1, csc3, wk1r, wk1i, wk3r, wk3i,
+ wd1r, wd1i, wd3r, wd3i;
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i;
+
+ mh = n >> 3;
+ m = 2 * mh;
+ j1 = m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[0] + a[j2];
+ x0i = a[1] + a[j2 + 1];
+ x1r = a[0] - a[j2];
+ x1i = a[1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[0] = x0r + x2r;
+ a[1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ a[j2] = x1r - x3i;
+ a[j2 + 1] = x1i + x3r;
+ a[j3] = x1r + x3i;
+ a[j3 + 1] = x1i - x3r;
+ wn4r = w[1];
+ csc1 = w[2];
+ csc3 = w[3];
+ wd1r = 1;
+ wd1i = 0;
+ wd3r = 1;
+ wd3i = 0;
+ k = 0;
+ for (j = 2; j < mh - 2; j += 4) {
+ k += 4;
+ wk1r = csc1 * (wd1r + w[k]);
+ wk1i = csc1 * (wd1i + w[k + 1]);
+ wk3r = csc3 * (wd3r + w[k + 2]);
+ wk3i = csc3 * (wd3i + w[k + 3]);
+ wd1r = w[k];
+ wd1i = w[k + 1];
+ wd3r = w[k + 2];
+ wd3i = w[k + 3];
+ j1 = j + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j] + a[j2];
+ x0i = a[j + 1] + a[j2 + 1];
+ x1r = a[j] - a[j2];
+ x1i = a[j + 1] - a[j2 + 1];
+ y0r = a[j + 2] + a[j2 + 2];
+ y0i = a[j + 3] + a[j2 + 3];
+ y1r = a[j + 2] - a[j2 + 2];
+ y1i = a[j + 3] - a[j2 + 3];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ y2r = a[j1 + 2] + a[j3 + 2];
+ y2i = a[j1 + 3] + a[j3 + 3];
+ y3r = a[j1 + 2] - a[j3 + 2];
+ y3i = a[j1 + 3] - a[j3 + 3];
+ a[j] = x0r + x2r;
+ a[j + 1] = x0i + x2i;
+ a[j + 2] = y0r + y2r;
+ a[j + 3] = y0i + y2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ a[j1 + 2] = y0r - y2r;
+ a[j1 + 3] = y0i - y2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1r * x0r - wk1i * x0i;
+ a[j2 + 1] = wk1r * x0i + wk1i * x0r;
+ x0r = y1r - y3i;
+ x0i = y1i + y3r;
+ a[j2 + 2] = wd1r * x0r - wd1i * x0i;
+ a[j2 + 3] = wd1r * x0i + wd1i * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3r * x0r + wk3i * x0i;
+ a[j3 + 1] = wk3r * x0i - wk3i * x0r;
+ x0r = y1r + y3i;
+ x0i = y1i - y3r;
+ a[j3 + 2] = wd3r * x0r + wd3i * x0i;
+ a[j3 + 3] = wd3r * x0i - wd3i * x0r;
+ j0 = m - j;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] + a[j2];
+ x0i = a[j0 + 1] + a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = a[j0 + 1] - a[j2 + 1];
+ y0r = a[j0 - 2] + a[j2 - 2];
+ y0i = a[j0 - 1] + a[j2 - 1];
+ y1r = a[j0 - 2] - a[j2 - 2];
+ y1i = a[j0 - 1] - a[j2 - 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ y2r = a[j1 - 2] + a[j3 - 2];
+ y2i = a[j1 - 1] + a[j3 - 1];
+ y3r = a[j1 - 2] - a[j3 - 2];
+ y3i = a[j1 - 1] - a[j3 - 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i + x2i;
+ a[j0 - 2] = y0r + y2r;
+ a[j0 - 1] = y0i + y2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ a[j1 - 2] = y0r - y2r;
+ a[j1 - 1] = y0i - y2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1i * x0r - wk1r * x0i;
+ a[j2 + 1] = wk1i * x0i + wk1r * x0r;
+ x0r = y1r - y3i;
+ x0i = y1i + y3r;
+ a[j2 - 2] = wd1i * x0r - wd1r * x0i;
+ a[j2 - 1] = wd1i * x0i + wd1r * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3i * x0r + wk3r * x0i;
+ a[j3 + 1] = wk3i * x0i - wk3r * x0r;
+ x0r = y1r + y3i;
+ x0i = y1i - y3r;
+ a[j3 - 2] = wd3i * x0r + wd3r * x0i;
+ a[j3 - 1] = wd3i * x0i - wd3r * x0r;
+ }
+ wk1r = csc1 * (wd1r + wn4r);
+ wk1i = csc1 * (wd1i + wn4r);
+ wk3r = csc3 * (wd3r - wn4r);
+ wk3i = csc3 * (wd3i - wn4r);
+ j0 = mh;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0 - 2] + a[j2 - 2];
+ x0i = a[j0 - 1] + a[j2 - 1];
+ x1r = a[j0 - 2] - a[j2 - 2];
+ x1i = a[j0 - 1] - a[j2 - 1];
+ x2r = a[j1 - 2] + a[j3 - 2];
+ x2i = a[j1 - 1] + a[j3 - 1];
+ x3r = a[j1 - 2] - a[j3 - 2];
+ x3i = a[j1 - 1] - a[j3 - 1];
+ a[j0 - 2] = x0r + x2r;
+ a[j0 - 1] = x0i + x2i;
+ a[j1 - 2] = x0r - x2r;
+ a[j1 - 1] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2 - 2] = wk1r * x0r - wk1i * x0i;
+ a[j2 - 1] = wk1r * x0i + wk1i * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3 - 2] = wk3r * x0r + wk3i * x0i;
+ a[j3 - 1] = wk3r * x0i - wk3i * x0r;
+ x0r = a[j0] + a[j2];
+ x0i = a[j0 + 1] + a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = a[j0 + 1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wn4r * (x0r - x0i);
+ a[j2 + 1] = wn4r * (x0i + x0r);
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = -wn4r * (x0r + x0i);
+ a[j3 + 1] = -wn4r * (x0i - x0r);
+ x0r = a[j0 + 2] + a[j2 + 2];
+ x0i = a[j0 + 3] + a[j2 + 3];
+ x1r = a[j0 + 2] - a[j2 + 2];
+ x1i = a[j0 + 3] - a[j2 + 3];
+ x2r = a[j1 + 2] + a[j3 + 2];
+ x2i = a[j1 + 3] + a[j3 + 3];
+ x3r = a[j1 + 2] - a[j3 + 2];
+ x3i = a[j1 + 3] - a[j3 + 3];
+ a[j0 + 2] = x0r + x2r;
+ a[j0 + 3] = x0i + x2i;
+ a[j1 + 2] = x0r - x2r;
+ a[j1 + 3] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2 + 2] = wk1i * x0r - wk1r * x0i;
+ a[j2 + 3] = wk1i * x0i + wk1r * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3 + 2] = wk3i * x0r + wk3r * x0i;
+ a[j3 + 3] = wk3i * x0i - wk3r * x0r;
+}
+
+
+void cftb1st(int n, float32 *a, float32 *w)
+{
+ int j, j0, j1, j2, j3, k, m, mh;
+ float32 wn4r, csc1, csc3, wk1r, wk1i, wk3r, wk3i,
+ wd1r, wd1i, wd3r, wd3i;
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i;
+
+ mh = n >> 3;
+ m = 2 * mh;
+ j1 = m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[0] + a[j2];
+ x0i = -a[1] - a[j2 + 1];
+ x1r = a[0] - a[j2];
+ x1i = -a[1] + a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[0] = x0r + x2r;
+ a[1] = x0i - x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i + x2i;
+ a[j2] = x1r + x3i;
+ a[j2 + 1] = x1i + x3r;
+ a[j3] = x1r - x3i;
+ a[j3 + 1] = x1i - x3r;
+ wn4r = w[1];
+ csc1 = w[2];
+ csc3 = w[3];
+ wd1r = 1;
+ wd1i = 0;
+ wd3r = 1;
+ wd3i = 0;
+ k = 0;
+ for (j = 2; j < mh - 2; j += 4) {
+ k += 4;
+ wk1r = csc1 * (wd1r + w[k]);
+ wk1i = csc1 * (wd1i + w[k + 1]);
+ wk3r = csc3 * (wd3r + w[k + 2]);
+ wk3i = csc3 * (wd3i + w[k + 3]);
+ wd1r = w[k];
+ wd1i = w[k + 1];
+ wd3r = w[k + 2];
+ wd3i = w[k + 3];
+ j1 = j + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j] + a[j2];
+ x0i = -a[j + 1] - a[j2 + 1];
+ x1r = a[j] - a[j2];
+ x1i = -a[j + 1] + a[j2 + 1];
+ y0r = a[j + 2] + a[j2 + 2];
+ y0i = -a[j + 3] - a[j2 + 3];
+ y1r = a[j + 2] - a[j2 + 2];
+ y1i = -a[j + 3] + a[j2 + 3];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ y2r = a[j1 + 2] + a[j3 + 2];
+ y2i = a[j1 + 3] + a[j3 + 3];
+ y3r = a[j1 + 2] - a[j3 + 2];
+ y3i = a[j1 + 3] - a[j3 + 3];
+ a[j] = x0r + x2r;
+ a[j + 1] = x0i - x2i;
+ a[j + 2] = y0r + y2r;
+ a[j + 3] = y0i - y2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i + x2i;
+ a[j1 + 2] = y0r - y2r;
+ a[j1 + 3] = y0i + y2i;
+ x0r = x1r + x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1r * x0r - wk1i * x0i;
+ a[j2 + 1] = wk1r * x0i + wk1i * x0r;
+ x0r = y1r + y3i;
+ x0i = y1i + y3r;
+ a[j2 + 2] = wd1r * x0r - wd1i * x0i;
+ a[j2 + 3] = wd1r * x0i + wd1i * x0r;
+ x0r = x1r - x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3r * x0r + wk3i * x0i;
+ a[j3 + 1] = wk3r * x0i - wk3i * x0r;
+ x0r = y1r - y3i;
+ x0i = y1i - y3r;
+ a[j3 + 2] = wd3r * x0r + wd3i * x0i;
+ a[j3 + 3] = wd3r * x0i - wd3i * x0r;
+ j0 = m - j;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] + a[j2];
+ x0i = -a[j0 + 1] - a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = -a[j0 + 1] + a[j2 + 1];
+ y0r = a[j0 - 2] + a[j2 - 2];
+ y0i = -a[j0 - 1] - a[j2 - 1];
+ y1r = a[j0 - 2] - a[j2 - 2];
+ y1i = -a[j0 - 1] + a[j2 - 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ y2r = a[j1 - 2] + a[j3 - 2];
+ y2i = a[j1 - 1] + a[j3 - 1];
+ y3r = a[j1 - 2] - a[j3 - 2];
+ y3i = a[j1 - 1] - a[j3 - 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i - x2i;
+ a[j0 - 2] = y0r + y2r;
+ a[j0 - 1] = y0i - y2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i + x2i;
+ a[j1 - 2] = y0r - y2r;
+ a[j1 - 1] = y0i + y2i;
+ x0r = x1r + x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1i * x0r - wk1r * x0i;
+ a[j2 + 1] = wk1i * x0i + wk1r * x0r;
+ x0r = y1r + y3i;
+ x0i = y1i + y3r;
+ a[j2 - 2] = wd1i * x0r - wd1r * x0i;
+ a[j2 - 1] = wd1i * x0i + wd1r * x0r;
+ x0r = x1r - x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3i * x0r + wk3r * x0i;
+ a[j3 + 1] = wk3i * x0i - wk3r * x0r;
+ x0r = y1r - y3i;
+ x0i = y1i - y3r;
+ a[j3 - 2] = wd3i * x0r + wd3r * x0i;
+ a[j3 - 1] = wd3i * x0i - wd3r * x0r;
+ }
+ wk1r = csc1 * (wd1r + wn4r);
+ wk1i = csc1 * (wd1i + wn4r);
+ wk3r = csc3 * (wd3r - wn4r);
+ wk3i = csc3 * (wd3i - wn4r);
+ j0 = mh;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0 - 2] + a[j2 - 2];
+ x0i = -a[j0 - 1] - a[j2 - 1];
+ x1r = a[j0 - 2] - a[j2 - 2];
+ x1i = -a[j0 - 1] + a[j2 - 1];
+ x2r = a[j1 - 2] + a[j3 - 2];
+ x2i = a[j1 - 1] + a[j3 - 1];
+ x3r = a[j1 - 2] - a[j3 - 2];
+ x3i = a[j1 - 1] - a[j3 - 1];
+ a[j0 - 2] = x0r + x2r;
+ a[j0 - 1] = x0i - x2i;
+ a[j1 - 2] = x0r - x2r;
+ a[j1 - 1] = x0i + x2i;
+ x0r = x1r + x3i;
+ x0i = x1i + x3r;
+ a[j2 - 2] = wk1r * x0r - wk1i * x0i;
+ a[j2 - 1] = wk1r * x0i + wk1i * x0r;
+ x0r = x1r - x3i;
+ x0i = x1i - x3r;
+ a[j3 - 2] = wk3r * x0r + wk3i * x0i;
+ a[j3 - 1] = wk3r * x0i - wk3i * x0r;
+ x0r = a[j0] + a[j2];
+ x0i = -a[j0 + 1] - a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = -a[j0 + 1] + a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i - x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i + x2i;
+ x0r = x1r + x3i;
+ x0i = x1i + x3r;
+ a[j2] = wn4r * (x0r - x0i);
+ a[j2 + 1] = wn4r * (x0i + x0r);
+ x0r = x1r - x3i;
+ x0i = x1i - x3r;
+ a[j3] = -wn4r * (x0r + x0i);
+ a[j3 + 1] = -wn4r * (x0i - x0r);
+ x0r = a[j0 + 2] + a[j2 + 2];
+ x0i = -a[j0 + 3] - a[j2 + 3];
+ x1r = a[j0 + 2] - a[j2 + 2];
+ x1i = -a[j0 + 3] + a[j2 + 3];
+ x2r = a[j1 + 2] + a[j3 + 2];
+ x2i = a[j1 + 3] + a[j3 + 3];
+ x3r = a[j1 + 2] - a[j3 + 2];
+ x3i = a[j1 + 3] - a[j3 + 3];
+ a[j0 + 2] = x0r + x2r;
+ a[j0 + 3] = x0i - x2i;
+ a[j1 + 2] = x0r - x2r;
+ a[j1 + 3] = x0i + x2i;
+ x0r = x1r + x3i;
+ x0i = x1i + x3r;
+ a[j2 + 2] = wk1i * x0r - wk1r * x0i;
+ a[j2 + 3] = wk1i * x0i + wk1r * x0r;
+ x0r = x1r - x3i;
+ x0i = x1i - x3r;
+ a[j3 + 2] = wk3i * x0r + wk3r * x0i;
+ a[j3 + 3] = wk3i * x0i - wk3r * x0r;
+}
+
+
+#ifdef USE_CDFT_THREADS
+struct cdft_arg_st {
+ int n0;
+ int n;
+ float32 *a;
+ int nw;
+ float32 *w;
+};
+typedef struct cdft_arg_st cdft_arg_t;
+
+
+void cftrec4_th(int n, float32 *a, int nw, float32 *w)
+{
+ void *cftrec1_th(void *p);
+ void *cftrec2_th(void *p);
+ int i, idiv4, m, nthread;
+ cdft_thread_t th[4];
+ cdft_arg_t ag[4];
+
+ nthread = 2;
+ idiv4 = 0;
+ m = n >> 1;
+ if (n > CDFT_4THREADS_BEGIN_N) {
+ nthread = 4;
+ idiv4 = 1;
+ m >>= 1;
+ }
+ for (i = 0; i < nthread; i++) {
+ ag[i].n0 = n;
+ ag[i].n = m;
+ ag[i].a = &a[i * m];
+ ag[i].nw = nw;
+ ag[i].w = w;
+ if (i != idiv4) {
+ cdft_thread_create(&th[i], cftrec1_th, &ag[i]);
+ } else {
+ cdft_thread_create(&th[i], cftrec2_th, &ag[i]);
+ }
+ }
+ for (i = 0; i < nthread; i++) {
+ cdft_thread_wait(th[i]);
+ }
+}
+
+
+void *cftrec1_th(void *p)
+{
+ int cfttree(int n, int j, int k, float32 *a, int nw, float32 *w);
+ void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w);
+ void cftmdl1(int n, float32 *a, float32 *w);
+ int isplt, j, k, m, n, n0, nw;
+ float32 *a, *w;
+
+ n0 = ((cdft_arg_t *) p)->n0;
+ n = ((cdft_arg_t *) p)->n;
+ a = ((cdft_arg_t *) p)->a;
+ nw = ((cdft_arg_t *) p)->nw;
+ w = ((cdft_arg_t *) p)->w;
+ m = n0;
+ while (m > 512) {
+ m >>= 2;
+ cftmdl1(m, &a[n - m], &w[nw - (m >> 1)]);
+ }
+ cftleaf(m, 1, &a[n - m], nw, w);
+ k = 0;
+ for (j = n - m; j > 0; j -= m) {
+ k++;
+ isplt = cfttree(m, j, k, a, nw, w);
+ cftleaf(m, isplt, &a[j - m], nw, w);
+ }
+ return (void *) 0;
+}
+
+
+void *cftrec2_th(void *p)
+{
+ int cfttree(int n, int j, int k, float32 *a, int nw, float32 *w);
+ void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w);
+ void cftmdl2(int n, float32 *a, float32 *w);
+ int isplt, j, k, m, n, n0, nw;
+ float32 *a, *w;
+
+ n0 = ((cdft_arg_t *) p)->n0;
+ n = ((cdft_arg_t *) p)->n;
+ a = ((cdft_arg_t *) p)->a;
+ nw = ((cdft_arg_t *) p)->nw;
+ w = ((cdft_arg_t *) p)->w;
+ k = 1;
+ m = n0;
+ while (m > 512) {
+ m >>= 2;
+ k <<= 2;
+ cftmdl2(m, &a[n - m], &w[nw - m]);
+ }
+ cftleaf(m, 0, &a[n - m], nw, w);
+ k >>= 1;
+ for (j = n - m; j > 0; j -= m) {
+ k++;
+ isplt = cfttree(m, j, k, a, nw, w);
+ cftleaf(m, isplt, &a[j - m], nw, w);
+ }
+ return (void *) 0;
+}
+#endif /* USE_CDFT_THREADS */
+
+
+void cftrec4(int n, float32 *a, int nw, float32 *w)
+{
+ int cfttree(int n, int j, int k, float32 *a, int nw, float32 *w);
+ void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w);
+ void cftmdl1(int n, float32 *a, float32 *w);
+ int isplt, j, k, m;
+
+ m = n;
+ while (m > 512) {
+ m >>= 2;
+ cftmdl1(m, &a[n - m], &w[nw - (m >> 1)]);
+ }
+ cftleaf(m, 1, &a[n - m], nw, w);
+ k = 0;
+ for (j = n - m; j > 0; j -= m) {
+ k++;
+ isplt = cfttree(m, j, k, a, nw, w);
+ cftleaf(m, isplt, &a[j - m], nw, w);
+ }
+}
+
+
+int cfttree(int n, int j, int k, float32 *a, int nw, float32 *w)
+{
+ void cftmdl1(int n, float32 *a, float32 *w);
+ void cftmdl2(int n, float32 *a, float32 *w);
+ int i, isplt, m;
+
+ if ((k & 3) != 0) {
+ isplt = k & 1;
+ if (isplt != 0) {
+ cftmdl1(n, &a[j - n], &w[nw - (n >> 1)]);
+ } else {
+ cftmdl2(n, &a[j - n], &w[nw - n]);
+ }
+ } else {
+ m = n;
+ for (i = k; (i & 3) == 0; i >>= 2) {
+ m <<= 2;
+ }
+ isplt = i & 1;
+ if (isplt != 0) {
+ while (m > 128) {
+ cftmdl1(m, &a[j - m], &w[nw - (m >> 1)]);
+ m >>= 2;
+ }
+ } else {
+ while (m > 128) {
+ cftmdl2(m, &a[j - m], &w[nw - m]);
+ m >>= 2;
+ }
+ }
+ }
+ return isplt;
+}
+
+
+void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w)
+{
+ void cftmdl1(int n, float32 *a, float32 *w);
+ void cftmdl2(int n, float32 *a, float32 *w);
+ void cftf161(float32 *a, float32 *w);
+ void cftf162(float32 *a, float32 *w);
+ void cftf081(float32 *a, float32 *w);
+ void cftf082(float32 *a, float32 *w);
+
+ if (n == 512) {
+ cftmdl1(128, a, &w[nw - 64]);
+ cftf161(a, &w[nw - 8]);
+ cftf162(&a[32], &w[nw - 32]);
+ cftf161(&a[64], &w[nw - 8]);
+ cftf161(&a[96], &w[nw - 8]);
+ cftmdl2(128, &a[128], &w[nw - 128]);
+ cftf161(&a[128], &w[nw - 8]);
+ cftf162(&a[160], &w[nw - 32]);
+ cftf161(&a[192], &w[nw - 8]);
+ cftf162(&a[224], &w[nw - 32]);
+ cftmdl1(128, &a[256], &w[nw - 64]);
+ cftf161(&a[256], &w[nw - 8]);
+ cftf162(&a[288], &w[nw - 32]);
+ cftf161(&a[320], &w[nw - 8]);
+ cftf161(&a[352], &w[nw - 8]);
+ if (isplt != 0) {
+ cftmdl1(128, &a[384], &w[nw - 64]);
+ cftf161(&a[480], &w[nw - 8]);
+ } else {
+ cftmdl2(128, &a[384], &w[nw - 128]);
+ cftf162(&a[480], &w[nw - 32]);
+ }
+ cftf161(&a[384], &w[nw - 8]);
+ cftf162(&a[416], &w[nw - 32]);
+ cftf161(&a[448], &w[nw - 8]);
+ } else {
+ cftmdl1(64, a, &w[nw - 32]);
+ cftf081(a, &w[nw - 8]);
+ cftf082(&a[16], &w[nw - 8]);
+ cftf081(&a[32], &w[nw - 8]);
+ cftf081(&a[48], &w[nw - 8]);
+ cftmdl2(64, &a[64], &w[nw - 64]);
+ cftf081(&a[64], &w[nw - 8]);
+ cftf082(&a[80], &w[nw - 8]);
+ cftf081(&a[96], &w[nw - 8]);
+ cftf082(&a[112], &w[nw - 8]);
+ cftmdl1(64, &a[128], &w[nw - 32]);
+ cftf081(&a[128], &w[nw - 8]);
+ cftf082(&a[144], &w[nw - 8]);
+ cftf081(&a[160], &w[nw - 8]);
+ cftf081(&a[176], &w[nw - 8]);
+ if (isplt != 0) {
+ cftmdl1(64, &a[192], &w[nw - 32]);
+ cftf081(&a[240], &w[nw - 8]);
+ } else {
+ cftmdl2(64, &a[192], &w[nw - 64]);
+ cftf082(&a[240], &w[nw - 8]);
+ }
+ cftf081(&a[192], &w[nw - 8]);
+ cftf082(&a[208], &w[nw - 8]);
+ cftf081(&a[224], &w[nw - 8]);
+ }
+}
+
+
+void cftmdl1(int n, float32 *a, float32 *w)
+{
+ int j, j0, j1, j2, j3, k, m, mh;
+ float32 wn4r, wk1r, wk1i, wk3r, wk3i;
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i;
+
+ mh = n >> 3;
+ m = 2 * mh;
+ j1 = m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[0] + a[j2];
+ x0i = a[1] + a[j2 + 1];
+ x1r = a[0] - a[j2];
+ x1i = a[1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[0] = x0r + x2r;
+ a[1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ a[j2] = x1r - x3i;
+ a[j2 + 1] = x1i + x3r;
+ a[j3] = x1r + x3i;
+ a[j3 + 1] = x1i - x3r;
+ wn4r = w[1];
+ k = 0;
+ for (j = 2; j < mh; j += 2) {
+ k += 4;
+ wk1r = w[k];
+ wk1i = w[k + 1];
+ wk3r = w[k + 2];
+ wk3i = w[k + 3];
+ j1 = j + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j] + a[j2];
+ x0i = a[j + 1] + a[j2 + 1];
+ x1r = a[j] - a[j2];
+ x1i = a[j + 1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[j] = x0r + x2r;
+ a[j + 1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1r * x0r - wk1i * x0i;
+ a[j2 + 1] = wk1r * x0i + wk1i * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3r * x0r + wk3i * x0i;
+ a[j3 + 1] = wk3r * x0i - wk3i * x0r;
+ j0 = m - j;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] + a[j2];
+ x0i = a[j0 + 1] + a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = a[j0 + 1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wk1i * x0r - wk1r * x0i;
+ a[j2 + 1] = wk1i * x0i + wk1r * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = wk3i * x0r + wk3r * x0i;
+ a[j3 + 1] = wk3i * x0i - wk3r * x0r;
+ }
+ j0 = mh;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] + a[j2];
+ x0i = a[j0 + 1] + a[j2 + 1];
+ x1r = a[j0] - a[j2];
+ x1i = a[j0 + 1] - a[j2 + 1];
+ x2r = a[j1] + a[j3];
+ x2i = a[j1 + 1] + a[j3 + 1];
+ x3r = a[j1] - a[j3];
+ x3i = a[j1 + 1] - a[j3 + 1];
+ a[j0] = x0r + x2r;
+ a[j0 + 1] = x0i + x2i;
+ a[j1] = x0r - x2r;
+ a[j1 + 1] = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ a[j2] = wn4r * (x0r - x0i);
+ a[j2 + 1] = wn4r * (x0i + x0r);
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ a[j3] = -wn4r * (x0r + x0i);
+ a[j3 + 1] = -wn4r * (x0i - x0r);
+}
+
+
+void cftmdl2(int n, float32 *a, float32 *w)
+{
+ int j, j0, j1, j2, j3, k, kr, m, mh;
+ float32 wn4r, wk1r, wk1i, wk3r, wk3i, wd1r, wd1i, wd3r, wd3i;
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, y0r, y0i, y2r, y2i;
+
+ mh = n >> 3;
+ m = 2 * mh;
+ wn4r = w[1];
+ j1 = m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[0] - a[j2 + 1];
+ x0i = a[1] + a[j2];
+ x1r = a[0] + a[j2 + 1];
+ x1i = a[1] - a[j2];
+ x2r = a[j1] - a[j3 + 1];
+ x2i = a[j1 + 1] + a[j3];
+ x3r = a[j1] + a[j3 + 1];
+ x3i = a[j1 + 1] - a[j3];
+ y0r = wn4r * (x2r - x2i);
+ y0i = wn4r * (x2i + x2r);
+ a[0] = x0r + y0r;
+ a[1] = x0i + y0i;
+ a[j1] = x0r - y0r;
+ a[j1 + 1] = x0i - y0i;
+ y0r = wn4r * (x3r - x3i);
+ y0i = wn4r * (x3i + x3r);
+ a[j2] = x1r - y0i;
+ a[j2 + 1] = x1i + y0r;
+ a[j3] = x1r + y0i;
+ a[j3 + 1] = x1i - y0r;
+ k = 0;
+ kr = 2 * m;
+ for (j = 2; j < mh; j += 2) {
+ k += 4;
+ wk1r = w[k];
+ wk1i = w[k + 1];
+ wk3r = w[k + 2];
+ wk3i = w[k + 3];
+ kr -= 4;
+ wd1i = w[kr];
+ wd1r = w[kr + 1];
+ wd3i = w[kr + 2];
+ wd3r = w[kr + 3];
+ j1 = j + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j] - a[j2 + 1];
+ x0i = a[j + 1] + a[j2];
+ x1r = a[j] + a[j2 + 1];
+ x1i = a[j + 1] - a[j2];
+ x2r = a[j1] - a[j3 + 1];
+ x2i = a[j1 + 1] + a[j3];
+ x3r = a[j1] + a[j3 + 1];
+ x3i = a[j1 + 1] - a[j3];
+ y0r = wk1r * x0r - wk1i * x0i;
+ y0i = wk1r * x0i + wk1i * x0r;
+ y2r = wd1r * x2r - wd1i * x2i;
+ y2i = wd1r * x2i + wd1i * x2r;
+ a[j] = y0r + y2r;
+ a[j + 1] = y0i + y2i;
+ a[j1] = y0r - y2r;
+ a[j1 + 1] = y0i - y2i;
+ y0r = wk3r * x1r + wk3i * x1i;
+ y0i = wk3r * x1i - wk3i * x1r;
+ y2r = wd3r * x3r + wd3i * x3i;
+ y2i = wd3r * x3i - wd3i * x3r;
+ a[j2] = y0r + y2r;
+ a[j2 + 1] = y0i + y2i;
+ a[j3] = y0r - y2r;
+ a[j3 + 1] = y0i - y2i;
+ j0 = m - j;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] - a[j2 + 1];
+ x0i = a[j0 + 1] + a[j2];
+ x1r = a[j0] + a[j2 + 1];
+ x1i = a[j0 + 1] - a[j2];
+ x2r = a[j1] - a[j3 + 1];
+ x2i = a[j1 + 1] + a[j3];
+ x3r = a[j1] + a[j3 + 1];
+ x3i = a[j1 + 1] - a[j3];
+ y0r = wd1i * x0r - wd1r * x0i;
+ y0i = wd1i * x0i + wd1r * x0r;
+ y2r = wk1i * x2r - wk1r * x2i;
+ y2i = wk1i * x2i + wk1r * x2r;
+ a[j0] = y0r + y2r;
+ a[j0 + 1] = y0i + y2i;
+ a[j1] = y0r - y2r;
+ a[j1 + 1] = y0i - y2i;
+ y0r = wd3i * x1r + wd3r * x1i;
+ y0i = wd3i * x1i - wd3r * x1r;
+ y2r = wk3i * x3r + wk3r * x3i;
+ y2i = wk3i * x3i - wk3r * x3r;
+ a[j2] = y0r + y2r;
+ a[j2 + 1] = y0i + y2i;
+ a[j3] = y0r - y2r;
+ a[j3 + 1] = y0i - y2i;
+ }
+ wk1r = w[m];
+ wk1i = w[m + 1];
+ j0 = mh;
+ j1 = j0 + m;
+ j2 = j1 + m;
+ j3 = j2 + m;
+ x0r = a[j0] - a[j2 + 1];
+ x0i = a[j0 + 1] + a[j2];
+ x1r = a[j0] + a[j2 + 1];
+ x1i = a[j0 + 1] - a[j2];
+ x2r = a[j1] - a[j3 + 1];
+ x2i = a[j1 + 1] + a[j3];
+ x3r = a[j1] + a[j3 + 1];
+ x3i = a[j1 + 1] - a[j3];
+ y0r = wk1r * x0r - wk1i * x0i;
+ y0i = wk1r * x0i + wk1i * x0r;
+ y2r = wk1i * x2r - wk1r * x2i;
+ y2i = wk1i * x2i + wk1r * x2r;
+ a[j0] = y0r + y2r;
+ a[j0 + 1] = y0i + y2i;
+ a[j1] = y0r - y2r;
+ a[j1 + 1] = y0i - y2i;
+ y0r = wk1i * x1r - wk1r * x1i;
+ y0i = wk1i * x1i + wk1r * x1r;
+ y2r = wk1r * x3r - wk1i * x3i;
+ y2i = wk1r * x3i + wk1i * x3r;
+ a[j2] = y0r - y2r;
+ a[j2 + 1] = y0i - y2i;
+ a[j3] = y0r + y2r;
+ a[j3 + 1] = y0i + y2i;
+}
+
+
+void cftfx41(int n, float32 *a, int nw, float32 *w)
+{
+ void cftf161(float32 *a, float32 *w);
+ void cftf162(float32 *a, float32 *w);
+ void cftf081(float32 *a, float32 *w);
+ void cftf082(float32 *a, float32 *w);
+
+ if (n == 128) {
+ cftf161(a, &w[nw - 8]);
+ cftf162(&a[32], &w[nw - 32]);
+ cftf161(&a[64], &w[nw - 8]);
+ cftf161(&a[96], &w[nw - 8]);
+ } else {
+ cftf081(a, &w[nw - 8]);
+ cftf082(&a[16], &w[nw - 8]);
+ cftf081(&a[32], &w[nw - 8]);
+ cftf081(&a[48], &w[nw - 8]);
+ }
+}
+
+
+void cftf161(float32 *a, float32 *w)
+{
+ float32 wn4r, wk1r, wk1i,
+ x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i,
+ y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i,
+ y8r, y8i, y9r, y9i, y10r, y10i, y11r, y11i,
+ y12r, y12i, y13r, y13i, y14r, y14i, y15r, y15i;
+
+ wn4r = w[1];
+ wk1r = w[2];
+ wk1i = w[3];
+ x0r = a[0] + a[16];
+ x0i = a[1] + a[17];
+ x1r = a[0] - a[16];
+ x1i = a[1] - a[17];
+ x2r = a[8] + a[24];
+ x2i = a[9] + a[25];
+ x3r = a[8] - a[24];
+ x3i = a[9] - a[25];
+ y0r = x0r + x2r;
+ y0i = x0i + x2i;
+ y4r = x0r - x2r;
+ y4i = x0i - x2i;
+ y8r = x1r - x3i;
+ y8i = x1i + x3r;
+ y12r = x1r + x3i;
+ y12i = x1i - x3r;
+ x0r = a[2] + a[18];
+ x0i = a[3] + a[19];
+ x1r = a[2] - a[18];
+ x1i = a[3] - a[19];
+ x2r = a[10] + a[26];
+ x2i = a[11] + a[27];
+ x3r = a[10] - a[26];
+ x3i = a[11] - a[27];
+ y1r = x0r + x2r;
+ y1i = x0i + x2i;
+ y5r = x0r - x2r;
+ y5i = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ y9r = wk1r * x0r - wk1i * x0i;
+ y9i = wk1r * x0i + wk1i * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ y13r = wk1i * x0r - wk1r * x0i;
+ y13i = wk1i * x0i + wk1r * x0r;
+ x0r = a[4] + a[20];
+ x0i = a[5] + a[21];
+ x1r = a[4] - a[20];
+ x1i = a[5] - a[21];
+ x2r = a[12] + a[28];
+ x2i = a[13] + a[29];
+ x3r = a[12] - a[28];
+ x3i = a[13] - a[29];
+ y2r = x0r + x2r;
+ y2i = x0i + x2i;
+ y6r = x0r - x2r;
+ y6i = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ y10r = wn4r * (x0r - x0i);
+ y10i = wn4r * (x0i + x0r);
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ y14r = wn4r * (x0r + x0i);
+ y14i = wn4r * (x0i - x0r);
+ x0r = a[6] + a[22];
+ x0i = a[7] + a[23];
+ x1r = a[6] - a[22];
+ x1i = a[7] - a[23];
+ x2r = a[14] + a[30];
+ x2i = a[15] + a[31];
+ x3r = a[14] - a[30];
+ x3i = a[15] - a[31];
+ y3r = x0r + x2r;
+ y3i = x0i + x2i;
+ y7r = x0r - x2r;
+ y7i = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ y11r = wk1i * x0r - wk1r * x0i;
+ y11i = wk1i * x0i + wk1r * x0r;
+ x0r = x1r + x3i;
+ x0i = x1i - x3r;
+ y15r = wk1r * x0r - wk1i * x0i;
+ y15i = wk1r * x0i + wk1i * x0r;
+ x0r = y12r - y14r;
+ x0i = y12i - y14i;
+ x1r = y12r + y14r;
+ x1i = y12i + y14i;
+ x2r = y13r - y15r;
+ x2i = y13i - y15i;
+ x3r = y13r + y15r;
+ x3i = y13i + y15i;
+ a[24] = x0r + x2r;
+ a[25] = x0i + x2i;
+ a[26] = x0r - x2r;
+ a[27] = x0i - x2i;
+ a[28] = x1r - x3i;
+ a[29] = x1i + x3r;
+ a[30] = x1r + x3i;
+ a[31] = x1i - x3r;
+ x0r = y8r + y10r;
+ x0i = y8i + y10i;
+ x1r = y8r - y10r;
+ x1i = y8i - y10i;
+ x2r = y9r + y11r;
+ x2i = y9i + y11i;
+ x3r = y9r - y11r;
+ x3i = y9i - y11i;
+ a[16] = x0r + x2r;
+ a[17] = x0i + x2i;
+ a[18] = x0r - x2r;
+ a[19] = x0i - x2i;
+ a[20] = x1r - x3i;
+ a[21] = x1i + x3r;
+ a[22] = x1r + x3i;
+ a[23] = x1i - x3r;
+ x0r = y5r - y7i;
+ x0i = y5i + y7r;
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ x0r = y5r + y7i;
+ x0i = y5i - y7r;
+ x3r = wn4r * (x0r - x0i);
+ x3i = wn4r * (x0i + x0r);
+ x0r = y4r - y6i;
+ x0i = y4i + y6r;
+ x1r = y4r + y6i;
+ x1i = y4i - y6r;
+ a[8] = x0r + x2r;
+ a[9] = x0i + x2i;
+ a[10] = x0r - x2r;
+ a[11] = x0i - x2i;
+ a[12] = x1r - x3i;
+ a[13] = x1i + x3r;
+ a[14] = x1r + x3i;
+ a[15] = x1i - x3r;
+ x0r = y0r + y2r;
+ x0i = y0i + y2i;
+ x1r = y0r - y2r;
+ x1i = y0i - y2i;
+ x2r = y1r + y3r;
+ x2i = y1i + y3i;
+ x3r = y1r - y3r;
+ x3i = y1i - y3i;
+ a[0] = x0r + x2r;
+ a[1] = x0i + x2i;
+ a[2] = x0r - x2r;
+ a[3] = x0i - x2i;
+ a[4] = x1r - x3i;
+ a[5] = x1i + x3r;
+ a[6] = x1r + x3i;
+ a[7] = x1i - x3r;
+}
+
+
+void cftf162(float32 *a, float32 *w)
+{
+ float32 wn4r, wk1r, wk1i, wk2r, wk2i, wk3r, wk3i,
+ x0r, x0i, x1r, x1i, x2r, x2i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i,
+ y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i,
+ y8r, y8i, y9r, y9i, y10r, y10i, y11r, y11i,
+ y12r, y12i, y13r, y13i, y14r, y14i, y15r, y15i;
+
+ wn4r = w[1];
+ wk1r = w[4];
+ wk1i = w[5];
+ wk3r = w[6];
+ wk3i = -w[7];
+ wk2r = w[8];
+ wk2i = w[9];
+ x1r = a[0] - a[17];
+ x1i = a[1] + a[16];
+ x0r = a[8] - a[25];
+ x0i = a[9] + a[24];
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ y0r = x1r + x2r;
+ y0i = x1i + x2i;
+ y4r = x1r - x2r;
+ y4i = x1i - x2i;
+ x1r = a[0] + a[17];
+ x1i = a[1] - a[16];
+ x0r = a[8] + a[25];
+ x0i = a[9] - a[24];
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ y8r = x1r - x2i;
+ y8i = x1i + x2r;
+ y12r = x1r + x2i;
+ y12i = x1i - x2r;
+ x0r = a[2] - a[19];
+ x0i = a[3] + a[18];
+ x1r = wk1r * x0r - wk1i * x0i;
+ x1i = wk1r * x0i + wk1i * x0r;
+ x0r = a[10] - a[27];
+ x0i = a[11] + a[26];
+ x2r = wk3i * x0r - wk3r * x0i;
+ x2i = wk3i * x0i + wk3r * x0r;
+ y1r = x1r + x2r;
+ y1i = x1i + x2i;
+ y5r = x1r - x2r;
+ y5i = x1i - x2i;
+ x0r = a[2] + a[19];
+ x0i = a[3] - a[18];
+ x1r = wk3r * x0r - wk3i * x0i;
+ x1i = wk3r * x0i + wk3i * x0r;
+ x0r = a[10] + a[27];
+ x0i = a[11] - a[26];
+ x2r = wk1r * x0r + wk1i * x0i;
+ x2i = wk1r * x0i - wk1i * x0r;
+ y9r = x1r - x2r;
+ y9i = x1i - x2i;
+ y13r = x1r + x2r;
+ y13i = x1i + x2i;
+ x0r = a[4] - a[21];
+ x0i = a[5] + a[20];
+ x1r = wk2r * x0r - wk2i * x0i;
+ x1i = wk2r * x0i + wk2i * x0r;
+ x0r = a[12] - a[29];
+ x0i = a[13] + a[28];
+ x2r = wk2i * x0r - wk2r * x0i;
+ x2i = wk2i * x0i + wk2r * x0r;
+ y2r = x1r + x2r;
+ y2i = x1i + x2i;
+ y6r = x1r - x2r;
+ y6i = x1i - x2i;
+ x0r = a[4] + a[21];
+ x0i = a[5] - a[20];
+ x1r = wk2i * x0r - wk2r * x0i;
+ x1i = wk2i * x0i + wk2r * x0r;
+ x0r = a[12] + a[29];
+ x0i = a[13] - a[28];
+ x2r = wk2r * x0r - wk2i * x0i;
+ x2i = wk2r * x0i + wk2i * x0r;
+ y10r = x1r - x2r;
+ y10i = x1i - x2i;
+ y14r = x1r + x2r;
+ y14i = x1i + x2i;
+ x0r = a[6] - a[23];
+ x0i = a[7] + a[22];
+ x1r = wk3r * x0r - wk3i * x0i;
+ x1i = wk3r * x0i + wk3i * x0r;
+ x0r = a[14] - a[31];
+ x0i = a[15] + a[30];
+ x2r = wk1i * x0r - wk1r * x0i;
+ x2i = wk1i * x0i + wk1r * x0r;
+ y3r = x1r + x2r;
+ y3i = x1i + x2i;
+ y7r = x1r - x2r;
+ y7i = x1i - x2i;
+ x0r = a[6] + a[23];
+ x0i = a[7] - a[22];
+ x1r = wk1i * x0r + wk1r * x0i;
+ x1i = wk1i * x0i - wk1r * x0r;
+ x0r = a[14] + a[31];
+ x0i = a[15] - a[30];
+ x2r = wk3i * x0r - wk3r * x0i;
+ x2i = wk3i * x0i + wk3r * x0r;
+ y11r = x1r + x2r;
+ y11i = x1i + x2i;
+ y15r = x1r - x2r;
+ y15i = x1i - x2i;
+ x1r = y0r + y2r;
+ x1i = y0i + y2i;
+ x2r = y1r + y3r;
+ x2i = y1i + y3i;
+ a[0] = x1r + x2r;
+ a[1] = x1i + x2i;
+ a[2] = x1r - x2r;
+ a[3] = x1i - x2i;
+ x1r = y0r - y2r;
+ x1i = y0i - y2i;
+ x2r = y1r - y3r;
+ x2i = y1i - y3i;
+ a[4] = x1r - x2i;
+ a[5] = x1i + x2r;
+ a[6] = x1r + x2i;
+ a[7] = x1i - x2r;
+ x1r = y4r - y6i;
+ x1i = y4i + y6r;
+ x0r = y5r - y7i;
+ x0i = y5i + y7r;
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ a[8] = x1r + x2r;
+ a[9] = x1i + x2i;
+ a[10] = x1r - x2r;
+ a[11] = x1i - x2i;
+ x1r = y4r + y6i;
+ x1i = y4i - y6r;
+ x0r = y5r + y7i;
+ x0i = y5i - y7r;
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ a[12] = x1r - x2i;
+ a[13] = x1i + x2r;
+ a[14] = x1r + x2i;
+ a[15] = x1i - x2r;
+ x1r = y8r + y10r;
+ x1i = y8i + y10i;
+ x2r = y9r - y11r;
+ x2i = y9i - y11i;
+ a[16] = x1r + x2r;
+ a[17] = x1i + x2i;
+ a[18] = x1r - x2r;
+ a[19] = x1i - x2i;
+ x1r = y8r - y10r;
+ x1i = y8i - y10i;
+ x2r = y9r + y11r;
+ x2i = y9i + y11i;
+ a[20] = x1r - x2i;
+ a[21] = x1i + x2r;
+ a[22] = x1r + x2i;
+ a[23] = x1i - x2r;
+ x1r = y12r - y14i;
+ x1i = y12i + y14r;
+ x0r = y13r + y15i;
+ x0i = y13i - y15r;
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ a[24] = x1r + x2r;
+ a[25] = x1i + x2i;
+ a[26] = x1r - x2r;
+ a[27] = x1i - x2i;
+ x1r = y12r + y14i;
+ x1i = y12i - y14r;
+ x0r = y13r - y15i;
+ x0i = y13i + y15r;
+ x2r = wn4r * (x0r - x0i);
+ x2i = wn4r * (x0i + x0r);
+ a[28] = x1r - x2i;
+ a[29] = x1i + x2r;
+ a[30] = x1r + x2i;
+ a[31] = x1i - x2r;
+}
+
+
+void cftf081(float32 *a, float32 *w)
+{
+ float32 wn4r, x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i,
+ y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i;
+
+ wn4r = w[1];
+ x0r = a[0] + a[8];
+ x0i = a[1] + a[9];
+ x1r = a[0] - a[8];
+ x1i = a[1] - a[9];
+ x2r = a[4] + a[12];
+ x2i = a[5] + a[13];
+ x3r = a[4] - a[12];
+ x3i = a[5] - a[13];
+ y0r = x0r + x2r;
+ y0i = x0i + x2i;
+ y2r = x0r - x2r;
+ y2i = x0i - x2i;
+ y1r = x1r - x3i;
+ y1i = x1i + x3r;
+ y3r = x1r + x3i;
+ y3i = x1i - x3r;
+ x0r = a[2] + a[10];
+ x0i = a[3] + a[11];
+ x1r = a[2] - a[10];
+ x1i = a[3] - a[11];
+ x2r = a[6] + a[14];
+ x2i = a[7] + a[15];
+ x3r = a[6] - a[14];
+ x3i = a[7] - a[15];
+ y4r = x0r + x2r;
+ y4i = x0i + x2i;
+ y6r = x0r - x2r;
+ y6i = x0i - x2i;
+ x0r = x1r - x3i;
+ x0i = x1i + x3r;
+ x2r = x1r + x3i;
+ x2i = x1i - x3r;
+ y5r = wn4r * (x0r - x0i);
+ y5i = wn4r * (x0r + x0i);
+ y7r = wn4r * (x2r - x2i);
+ y7i = wn4r * (x2r + x2i);
+ a[8] = y1r + y5r;
+ a[9] = y1i + y5i;
+ a[10] = y1r - y5r;
+ a[11] = y1i - y5i;
+ a[12] = y3r - y7i;
+ a[13] = y3i + y7r;
+ a[14] = y3r + y7i;
+ a[15] = y3i - y7r;
+ a[0] = y0r + y4r;
+ a[1] = y0i + y4i;
+ a[2] = y0r - y4r;
+ a[3] = y0i - y4i;
+ a[4] = y2r - y6i;
+ a[5] = y2i + y6r;
+ a[6] = y2r + y6i;
+ a[7] = y2i - y6r;
+}
+
+
+void cftf082(float32 *a, float32 *w)
+{
+ float32 wn4r, wk1r, wk1i, x0r, x0i, x1r, x1i,
+ y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i,
+ y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i;
+
+ wn4r = w[1];
+ wk1r = w[2];
+ wk1i = w[3];
+ y0r = a[0] - a[9];
+ y0i = a[1] + a[8];
+ y1r = a[0] + a[9];
+ y1i = a[1] - a[8];
+ x0r = a[4] - a[13];
+ x0i = a[5] + a[12];
+ y2r = wn4r * (x0r - x0i);
+ y2i = wn4r * (x0i + x0r);
+ x0r = a[4] + a[13];
+ x0i = a[5] - a[12];
+ y3r = wn4r * (x0r - x0i);
+ y3i = wn4r * (x0i + x0r);
+ x0r = a[2] - a[11];
+ x0i = a[3] + a[10];
+ y4r = wk1r * x0r - wk1i * x0i;
+ y4i = wk1r * x0i + wk1i * x0r;
+ x0r = a[2] + a[11];
+ x0i = a[3] - a[10];
+ y5r = wk1i * x0r - wk1r * x0i;
+ y5i = wk1i * x0i + wk1r * x0r;
+ x0r = a[6] - a[15];
+ x0i = a[7] + a[14];
+ y6r = wk1i * x0r - wk1r * x0i;
+ y6i = wk1i * x0i + wk1r * x0r;
+ x0r = a[6] + a[15];
+ x0i = a[7] - a[14];
+ y7r = wk1r * x0r - wk1i * x0i;
+ y7i = wk1r * x0i + wk1i * x0r;
+ x0r = y0r + y2r;
+ x0i = y0i + y2i;
+ x1r = y4r + y6r;
+ x1i = y4i + y6i;
+ a[0] = x0r + x1r;
+ a[1] = x0i + x1i;
+ a[2] = x0r - x1r;
+ a[3] = x0i - x1i;
+ x0r = y0r - y2r;
+ x0i = y0i - y2i;
+ x1r = y4r - y6r;
+ x1i = y4i - y6i;
+ a[4] = x0r - x1i;
+ a[5] = x0i + x1r;
+ a[6] = x0r + x1i;
+ a[7] = x0i - x1r;
+ x0r = y1r - y3i;
+ x0i = y1i + y3r;
+ x1r = y5r - y7r;
+ x1i = y5i - y7i;
+ a[8] = x0r + x1r;
+ a[9] = x0i + x1i;
+ a[10] = x0r - x1r;
+ a[11] = x0i - x1i;
+ x0r = y1r + y3i;
+ x0i = y1i - y3r;
+ x1r = y5r + y7r;
+ x1i = y5i + y7i;
+ a[12] = x0r - x1i;
+ a[13] = x0i + x1r;
+ a[14] = x0r + x1i;
+ a[15] = x0i - x1r;
+}
+
+
+void cftf040(float32 *a)
+{
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i;
+
+ x0r = a[0] + a[4];
+ x0i = a[1] + a[5];
+ x1r = a[0] - a[4];
+ x1i = a[1] - a[5];
+ x2r = a[2] + a[6];
+ x2i = a[3] + a[7];
+ x3r = a[2] - a[6];
+ x3i = a[3] - a[7];
+ a[0] = x0r + x2r;
+ a[1] = x0i + x2i;
+ a[2] = x1r - x3i;
+ a[3] = x1i + x3r;
+ a[4] = x0r - x2r;
+ a[5] = x0i - x2i;
+ a[6] = x1r + x3i;
+ a[7] = x1i - x3r;
+}
+
+
+void cftb040(float32 *a)
+{
+ float32 x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i;
+
+ x0r = a[0] + a[4];
+ x0i = a[1] + a[5];
+ x1r = a[0] - a[4];
+ x1i = a[1] - a[5];
+ x2r = a[2] + a[6];
+ x2i = a[3] + a[7];
+ x3r = a[2] - a[6];
+ x3i = a[3] - a[7];
+ a[0] = x0r + x2r;
+ a[1] = x0i + x2i;
+ a[2] = x1r + x3i;
+ a[3] = x1i - x3r;
+ a[4] = x0r - x2r;
+ a[5] = x0i - x2i;
+ a[6] = x1r - x3i;
+ a[7] = x1i + x3r;
+}
+
+
+void cftx020(float32 *a)
+{
+ float32 x0r, x0i;
+
+ x0r = a[0] - a[2];
+ x0i = a[1] - a[3];
+ a[0] += a[2];
+ a[1] += a[3];
+ a[2] = x0r;
+ a[3] = x0i;
+}
+
+
+void rftfsub(int n, float32 *a, int nc, float32 *c)
+{
+ int j, k, kk, ks, m;
+ float32 wkr, wki, xr, xi, yr, yi;
+
+ m = n >> 1;
+ ks = 2 * nc / m;
+ kk = 0;
+ for (j = 2; j < m; j += 2) {
+ k = n - j;
+ kk += ks;
+ wkr = 0.5 - c[nc - kk];
+ wki = c[kk];
+ xr = a[j] - a[k];
+ xi = a[j + 1] + a[k + 1];
+ yr = wkr * xr - wki * xi;
+ yi = wkr * xi + wki * xr;
+ a[j] -= yr;
+ a[j + 1] -= yi;
+ a[k] += yr;
+ a[k + 1] -= yi;
+ }
+}
+
+
+void rftbsub(int n, float32 *a, int nc, float32 *c)
+{
+ int j, k, kk, ks, m;
+ float32 wkr, wki, xr, xi, yr, yi;
+
+ m = n >> 1;
+ ks = 2 * nc / m;
+ kk = 0;
+ for (j = 2; j < m; j += 2) {
+ k = n - j;
+ kk += ks;
+ wkr = 0.5 - c[nc - kk];
+ wki = c[kk];
+ xr = a[j] - a[k];
+ xi = a[j + 1] + a[k + 1];
+ yr = wkr * xr + wki * xi;
+ yi = wkr * xi - wki * xr;
+ a[j] -= yr;
+ a[j + 1] -= yi;
+ a[k] += yr;
+ a[k + 1] -= yi;
+ }
+}
+
+
+void dctsub(int n, float32 *a, int nc, float32 *c)
+{
+ int j, k, kk, ks, m;
+ float32 wkr, wki, xr;
+
+ m = n >> 1;
+ ks = nc / n;
+ kk = 0;
+ for (j = 1; j < m; j++) {
+ k = n - j;
+ kk += ks;
+ wkr = c[kk] - c[nc - kk];
+ wki = c[kk] + c[nc - kk];
+ xr = wki * a[j] - wkr * a[k];
+ a[j] = wkr * a[j] + wki * a[k];
+ a[k] = xr;
+ }
+ a[m] *= c[0];
+}
+
+
+void dstsub(int n, float32 *a, int nc, float32 *c)
+{
+ int j, k, kk, ks, m;
+ float32 wkr, wki, xr;
+
+ m = n >> 1;
+ ks = nc / n;
+ kk = 0;
+ for (j = 1; j < m; j++) {
+ k = n - j;
+ kk += ks;
+ wkr = c[kk] - c[nc - kk];
+ wki = c[kk] + c[nc - kk];
+ xr = wki * a[k] - wkr * a[j];
+ a[k] = wkr * a[k] + wki * a[j];
+ a[j] = xr;
+ }
+ a[m] *= c[0];
}
}
--
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