/* ----------------------------------------------------------------------- Copyright: 2010-2021, imec Vision Lab, University of Antwerp 2014-2021, CWI, Amsterdam Contact: astra@astra-toolbox.com Website: http://www.astra-toolbox.com/ This file is part of the ASTRA Toolbox. The ASTRA Toolbox is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. The ASTRA Toolbox is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with the ASTRA Toolbox. If not, see . ----------------------------------------------------------------------- */ #include "astra/Fourier.h" #include namespace astra { /* Copyright Takuya OOURA, 1996-2001 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] X[k] = sum_j=0^n-1 x[j]*exp(2*pi*i*j*k/n), 0<=k X[k] = sum_j=0^n-1 x[j]*exp(-2*pi*i*j*k/n), 0<=k ip[0] = 0; // first time only cdft(2*n, 1, a, ip, w); 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= 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] 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 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 ip[0] = 0; // first time only rdft(n, 1, a, ip, w); 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 *) output data a[2*k] = R[k], 0<=k input data a[2*j] = R[j], 0<=j= 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] IDCT (excluding scale) C[k] = sum_j=0^n-1 a[j]*cos(pi*j*(k+1/2)/n), 0<=k DCT C[k] = sum_j=0^n-1 a[j]*cos(pi*(j+1/2)*k/n), 0<=k ip[0] = 0; // first time only ddct(n, 1, a, ip, w); 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= 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] IDST (excluding scale) S[k] = sum_j=1^n A[j]*sin(pi*j*(k+1/2)/n), 0<=k DST S[k] = sum_j=0^n-1 a[j]*sin(pi*(j+1/2)*k/n), 0 ip[0] = 0; // first time only ddst(n, 1, a, ip, w); 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 *) input data a[j] = A[j], 0 output data a[k] = S[k], 0= 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= 2, n = power of 2 a[0...n-1] :input/output data (float32 *) output data a[k] = S[k], 0= 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. */ static int cfttree(int n, int j, int k, float32 *a, int nw, float32 *w); static void bitrv208(float32 *a); static void bitrv208neg(float32 *a); static void bitrv216(float32 *a); static void bitrv216neg(float32 *a); static void bitrv2conj(int n, int *ip, float32 *a); static void bitrv2(int n, int *ip, float32 *a); static void cftb040(float32 *a); static void cftb1st(int n, float32 *a, float32 *w); static void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w); static void cftf040(float32 *a); static void cftf081(float32 *a, float32 *w); static void cftf082(float32 *a, float32 *w); static void cftf161(float32 *a, float32 *w); static void cftf162(float32 *a, float32 *w); static void cftf1st(int n, float32 *a, float32 *w); static void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w); static void cftfx41(int n, float32 *a, int nw, float32 *w); static void cftleaf(int n, int isplt, float32 *a, int nw, float32 *w); static void cftmdl1(int n, float32 *a, float32 *w); static void cftmdl2(int n, float32 *a, float32 *w); static void *cftrec1_th(void *p); static void *cftrec2_th(void *p); static void cftrec4(int n, float32 *a, int nw, float32 *w); static void cftx020(float32 *a); static void dctsub(int n, float32 *a, int nc, float32 *c); static void dstsub(int n, float32 *a, int nc, float32 *c); static void makect(int nc, int *ip, float32 *c); static void makeipt(int nw, int *ip); static void makewt(int nw, int *ip, float32 *w); static void rftbsub(int n, float32 *a, int nc, float32 *c); static void rftfsub(int n, float32 *a, int nc, float32 *c); #ifdef USE_CDFT_THREADS static void cftrec4_th(int n, float32 *a, int nw, float32 *w); #endif /* USE_CDFT_THREADS */ _AstraExport void cdft(int n, int isgn, float32 *a, int *ip, 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); } } _AstraExport void rdft(int n, int isgn, float32 *a, int *ip, float32 *w) { 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); } } } _AstraExport void ddct(int n, int isgn, float32 *a, int *ip, float32 *w) { 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; } } _AstraExport void ddst(int n, int isgn, float32 *a, int *ip, float32 *w) { 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; } } _AstraExport void dfct(int n, float32 *a, float32 *t, int *ip, float32 *w) { 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]; } } _AstraExport void dfst(int n, float32 *a, float32 *t, int *ip, float32 *w) { 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 -------- */ static void makewt(int nw, int *ip, float32 *w) { 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; } } } static 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; } } static 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 #include #include #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 #include #include #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 */ static void cftfsub(int n, float32 *a, int *ip, int nw, float32 *w) { 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); } } static void cftbsub(int n, float32 *a, int *ip, int nw, float32 *w) { 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); } } static 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; } } } static 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]; } } } static 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; } static 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; } static 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; } static 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; } static 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; } static 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; static void cftrec4_th(int n, float32 *a, int nw, float32 *w) { 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]); } } static void *cftrec1_th(void *p) { 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; } static void *cftrec2_th(void *p) { 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 */ static void cftrec4(int n, float32 *a, int nw, 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) { 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; } static void cftleaf(int n, int isplt, float32 *a, int nw, 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]); } } static 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); } static 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; } static void cftfx41(int n, float32 *a, int nw, 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]); } } static 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; } static 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; } static 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; } static 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; } static 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; } static 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; } static 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; } static 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; } } static 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; } } static 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]; } static 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]; } }