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-rw-r--r--src/opus-1.0.2/celt/kiss_fft.c722
1 files changed, 0 insertions, 722 deletions
diff --git a/src/opus-1.0.2/celt/kiss_fft.c b/src/opus-1.0.2/celt/kiss_fft.c
deleted file mode 100644
index dcd69686..00000000
--- a/src/opus-1.0.2/celt/kiss_fft.c
+++ /dev/null
@@ -1,722 +0,0 @@
-/*Copyright (c) 2003-2004, Mark Borgerding
- Lots of modifications by Jean-Marc Valin
- Copyright (c) 2005-2007, Xiph.Org Foundation
- Copyright (c) 2008, Xiph.Org Foundation, CSIRO
-
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
-
- * Redistributions of source code must retain the above copyright notice,
- this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above copyright notice,
- this list of conditions and the following disclaimer in the
- documentation and/or other materials provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- POSSIBILITY OF SUCH DAMAGE.*/
-
-/* This code is originally from Mark Borgerding's KISS-FFT but has been
- heavily modified to better suit Opus */
-
-#ifndef SKIP_CONFIG_H
-# ifdef HAVE_CONFIG_H
-# include "config.h"
-# endif
-#endif
-
-#include "_kiss_fft_guts.h"
-#include "arch.h"
-#include "os_support.h"
-#include "mathops.h"
-#include "stack_alloc.h"
-#include "os_support.h"
-
-/* The guts header contains all the multiplication and addition macros that are defined for
- complex numbers. It also delares the kf_ internal functions.
-*/
-
-static void kf_bfly2(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- kiss_fft_cpx * Fout2;
- const kiss_twiddle_cpx * tw1;
- int i,j;
- kiss_fft_cpx * Fout_beg = Fout;
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- Fout2 = Fout + m;
- tw1 = st->twiddles;
- for(j=0;j<m;j++)
- {
- kiss_fft_cpx t;
- Fout->r = SHR32(Fout->r, 1);Fout->i = SHR32(Fout->i, 1);
- Fout2->r = SHR32(Fout2->r, 1);Fout2->i = SHR32(Fout2->i, 1);
- C_MUL (t, *Fout2 , *tw1);
- tw1 += fstride;
- C_SUB( *Fout2 , *Fout , t );
- C_ADDTO( *Fout , t );
- ++Fout2;
- ++Fout;
- }
- }
-}
-
-static void ki_bfly2(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- kiss_fft_cpx * Fout2;
- const kiss_twiddle_cpx * tw1;
- kiss_fft_cpx t;
- int i,j;
- kiss_fft_cpx * Fout_beg = Fout;
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- Fout2 = Fout + m;
- tw1 = st->twiddles;
- for(j=0;j<m;j++)
- {
- C_MULC (t, *Fout2 , *tw1);
- tw1 += fstride;
- C_SUB( *Fout2 , *Fout , t );
- C_ADDTO( *Fout , t );
- ++Fout2;
- ++Fout;
- }
- }
-}
-
-static void kf_bfly4(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- const kiss_twiddle_cpx *tw1,*tw2,*tw3;
- kiss_fft_cpx scratch[6];
- const size_t m2=2*m;
- const size_t m3=3*m;
- int i, j;
-
- kiss_fft_cpx * Fout_beg = Fout;
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- tw3 = tw2 = tw1 = st->twiddles;
- for (j=0;j<m;j++)
- {
- C_MUL4(scratch[0],Fout[m] , *tw1 );
- C_MUL4(scratch[1],Fout[m2] , *tw2 );
- C_MUL4(scratch[2],Fout[m3] , *tw3 );
-
- Fout->r = PSHR32(Fout->r, 2);
- Fout->i = PSHR32(Fout->i, 2);
- C_SUB( scratch[5] , *Fout, scratch[1] );
- C_ADDTO(*Fout, scratch[1]);
- C_ADD( scratch[3] , scratch[0] , scratch[2] );
- C_SUB( scratch[4] , scratch[0] , scratch[2] );
- Fout[m2].r = PSHR32(Fout[m2].r, 2);
- Fout[m2].i = PSHR32(Fout[m2].i, 2);
- C_SUB( Fout[m2], *Fout, scratch[3] );
- tw1 += fstride;
- tw2 += fstride*2;
- tw3 += fstride*3;
- C_ADDTO( *Fout , scratch[3] );
-
- Fout[m].r = scratch[5].r + scratch[4].i;
- Fout[m].i = scratch[5].i - scratch[4].r;
- Fout[m3].r = scratch[5].r - scratch[4].i;
- Fout[m3].i = scratch[5].i + scratch[4].r;
- ++Fout;
- }
- }
-}
-
-static void ki_bfly4(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- const kiss_twiddle_cpx *tw1,*tw2,*tw3;
- kiss_fft_cpx scratch[6];
- const size_t m2=2*m;
- const size_t m3=3*m;
- int i, j;
-
- kiss_fft_cpx * Fout_beg = Fout;
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- tw3 = tw2 = tw1 = st->twiddles;
- for (j=0;j<m;j++)
- {
- C_MULC(scratch[0],Fout[m] , *tw1 );
- C_MULC(scratch[1],Fout[m2] , *tw2 );
- C_MULC(scratch[2],Fout[m3] , *tw3 );
-
- C_SUB( scratch[5] , *Fout, scratch[1] );
- C_ADDTO(*Fout, scratch[1]);
- C_ADD( scratch[3] , scratch[0] , scratch[2] );
- C_SUB( scratch[4] , scratch[0] , scratch[2] );
- C_SUB( Fout[m2], *Fout, scratch[3] );
- tw1 += fstride;
- tw2 += fstride*2;
- tw3 += fstride*3;
- C_ADDTO( *Fout , scratch[3] );
-
- Fout[m].r = scratch[5].r - scratch[4].i;
- Fout[m].i = scratch[5].i + scratch[4].r;
- Fout[m3].r = scratch[5].r + scratch[4].i;
- Fout[m3].i = scratch[5].i - scratch[4].r;
- ++Fout;
- }
- }
-}
-
-#ifndef RADIX_TWO_ONLY
-
-static void kf_bfly3(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- int i;
- size_t k;
- const size_t m2 = 2*m;
- const kiss_twiddle_cpx *tw1,*tw2;
- kiss_fft_cpx scratch[5];
- kiss_twiddle_cpx epi3;
-
- kiss_fft_cpx * Fout_beg = Fout;
- epi3 = st->twiddles[fstride*m];
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- tw1=tw2=st->twiddles;
- k=m;
- do {
- C_FIXDIV(*Fout,3); C_FIXDIV(Fout[m],3); C_FIXDIV(Fout[m2],3);
-
- C_MUL(scratch[1],Fout[m] , *tw1);
- C_MUL(scratch[2],Fout[m2] , *tw2);
-
- C_ADD(scratch[3],scratch[1],scratch[2]);
- C_SUB(scratch[0],scratch[1],scratch[2]);
- tw1 += fstride;
- tw2 += fstride*2;
-
- Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
- Fout[m].i = Fout->i - HALF_OF(scratch[3].i);
-
- C_MULBYSCALAR( scratch[0] , epi3.i );
-
- C_ADDTO(*Fout,scratch[3]);
-
- Fout[m2].r = Fout[m].r + scratch[0].i;
- Fout[m2].i = Fout[m].i - scratch[0].r;
-
- Fout[m].r -= scratch[0].i;
- Fout[m].i += scratch[0].r;
-
- ++Fout;
- } while(--k);
- }
-}
-
-static void ki_bfly3(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- int i, k;
- const size_t m2 = 2*m;
- const kiss_twiddle_cpx *tw1,*tw2;
- kiss_fft_cpx scratch[5];
- kiss_twiddle_cpx epi3;
-
- kiss_fft_cpx * Fout_beg = Fout;
- epi3 = st->twiddles[fstride*m];
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- tw1=tw2=st->twiddles;
- k=m;
- do{
-
- C_MULC(scratch[1],Fout[m] , *tw1);
- C_MULC(scratch[2],Fout[m2] , *tw2);
-
- C_ADD(scratch[3],scratch[1],scratch[2]);
- C_SUB(scratch[0],scratch[1],scratch[2]);
- tw1 += fstride;
- tw2 += fstride*2;
-
- Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
- Fout[m].i = Fout->i - HALF_OF(scratch[3].i);
-
- C_MULBYSCALAR( scratch[0] , -epi3.i );
-
- C_ADDTO(*Fout,scratch[3]);
-
- Fout[m2].r = Fout[m].r + scratch[0].i;
- Fout[m2].i = Fout[m].i - scratch[0].r;
-
- Fout[m].r -= scratch[0].i;
- Fout[m].i += scratch[0].r;
-
- ++Fout;
- }while(--k);
- }
-}
-
-static void kf_bfly5(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- kiss_fft_cpx *Fout0,*Fout1,*Fout2,*Fout3,*Fout4;
- int i, u;
- kiss_fft_cpx scratch[13];
- const kiss_twiddle_cpx * twiddles = st->twiddles;
- const kiss_twiddle_cpx *tw;
- kiss_twiddle_cpx ya,yb;
- kiss_fft_cpx * Fout_beg = Fout;
-
- ya = twiddles[fstride*m];
- yb = twiddles[fstride*2*m];
- tw=st->twiddles;
-
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- Fout0=Fout;
- Fout1=Fout0+m;
- Fout2=Fout0+2*m;
- Fout3=Fout0+3*m;
- Fout4=Fout0+4*m;
-
- for ( u=0; u<m; ++u ) {
- C_FIXDIV( *Fout0,5); C_FIXDIV( *Fout1,5); C_FIXDIV( *Fout2,5); C_FIXDIV( *Fout3,5); C_FIXDIV( *Fout4,5);
- scratch[0] = *Fout0;
-
- C_MUL(scratch[1] ,*Fout1, tw[u*fstride]);
- C_MUL(scratch[2] ,*Fout2, tw[2*u*fstride]);
- C_MUL(scratch[3] ,*Fout3, tw[3*u*fstride]);
- C_MUL(scratch[4] ,*Fout4, tw[4*u*fstride]);
-
- C_ADD( scratch[7],scratch[1],scratch[4]);
- C_SUB( scratch[10],scratch[1],scratch[4]);
- C_ADD( scratch[8],scratch[2],scratch[3]);
- C_SUB( scratch[9],scratch[2],scratch[3]);
-
- Fout0->r += scratch[7].r + scratch[8].r;
- Fout0->i += scratch[7].i + scratch[8].i;
-
- scratch[5].r = scratch[0].r + S_MUL(scratch[7].r,ya.r) + S_MUL(scratch[8].r,yb.r);
- scratch[5].i = scratch[0].i + S_MUL(scratch[7].i,ya.r) + S_MUL(scratch[8].i,yb.r);
-
- scratch[6].r = S_MUL(scratch[10].i,ya.i) + S_MUL(scratch[9].i,yb.i);
- scratch[6].i = -S_MUL(scratch[10].r,ya.i) - S_MUL(scratch[9].r,yb.i);
-
- C_SUB(*Fout1,scratch[5],scratch[6]);
- C_ADD(*Fout4,scratch[5],scratch[6]);
-
- scratch[11].r = scratch[0].r + S_MUL(scratch[7].r,yb.r) + S_MUL(scratch[8].r,ya.r);
- scratch[11].i = scratch[0].i + S_MUL(scratch[7].i,yb.r) + S_MUL(scratch[8].i,ya.r);
- scratch[12].r = - S_MUL(scratch[10].i,yb.i) + S_MUL(scratch[9].i,ya.i);
- scratch[12].i = S_MUL(scratch[10].r,yb.i) - S_MUL(scratch[9].r,ya.i);
-
- C_ADD(*Fout2,scratch[11],scratch[12]);
- C_SUB(*Fout3,scratch[11],scratch[12]);
-
- ++Fout0;++Fout1;++Fout2;++Fout3;++Fout4;
- }
- }
-}
-
-static void ki_bfly5(
- kiss_fft_cpx * Fout,
- const size_t fstride,
- const kiss_fft_state *st,
- int m,
- int N,
- int mm
- )
-{
- kiss_fft_cpx *Fout0,*Fout1,*Fout2,*Fout3,*Fout4;
- int i, u;
- kiss_fft_cpx scratch[13];
- const kiss_twiddle_cpx * twiddles = st->twiddles;
- const kiss_twiddle_cpx *tw;
- kiss_twiddle_cpx ya,yb;
- kiss_fft_cpx * Fout_beg = Fout;
-
- ya = twiddles[fstride*m];
- yb = twiddles[fstride*2*m];
- tw=st->twiddles;
-
- for (i=0;i<N;i++)
- {
- Fout = Fout_beg + i*mm;
- Fout0=Fout;
- Fout1=Fout0+m;
- Fout2=Fout0+2*m;
- Fout3=Fout0+3*m;
- Fout4=Fout0+4*m;
-
- for ( u=0; u<m; ++u ) {
- scratch[0] = *Fout0;
-
- C_MULC(scratch[1] ,*Fout1, tw[u*fstride]);
- C_MULC(scratch[2] ,*Fout2, tw[2*u*fstride]);
- C_MULC(scratch[3] ,*Fout3, tw[3*u*fstride]);
- C_MULC(scratch[4] ,*Fout4, tw[4*u*fstride]);
-
- C_ADD( scratch[7],scratch[1],scratch[4]);
- C_SUB( scratch[10],scratch[1],scratch[4]);
- C_ADD( scratch[8],scratch[2],scratch[3]);
- C_SUB( scratch[9],scratch[2],scratch[3]);
-
- Fout0->r += scratch[7].r + scratch[8].r;
- Fout0->i += scratch[7].i + scratch[8].i;
-
- scratch[5].r = scratch[0].r + S_MUL(scratch[7].r,ya.r) + S_MUL(scratch[8].r,yb.r);
- scratch[5].i = scratch[0].i + S_MUL(scratch[7].i,ya.r) + S_MUL(scratch[8].i,yb.r);
-
- scratch[6].r = -S_MUL(scratch[10].i,ya.i) - S_MUL(scratch[9].i,yb.i);
- scratch[6].i = S_MUL(scratch[10].r,ya.i) + S_MUL(scratch[9].r,yb.i);
-
- C_SUB(*Fout1,scratch[5],scratch[6]);
- C_ADD(*Fout4,scratch[5],scratch[6]);
-
- scratch[11].r = scratch[0].r + S_MUL(scratch[7].r,yb.r) + S_MUL(scratch[8].r,ya.r);
- scratch[11].i = scratch[0].i + S_MUL(scratch[7].i,yb.r) + S_MUL(scratch[8].i,ya.r);
- scratch[12].r = S_MUL(scratch[10].i,yb.i) - S_MUL(scratch[9].i,ya.i);
- scratch[12].i = -S_MUL(scratch[10].r,yb.i) + S_MUL(scratch[9].r,ya.i);
-
- C_ADD(*Fout2,scratch[11],scratch[12]);
- C_SUB(*Fout3,scratch[11],scratch[12]);
-
- ++Fout0;++Fout1;++Fout2;++Fout3;++Fout4;
- }
- }
-}
-
-#endif
-
-
-#ifdef CUSTOM_MODES
-
-static
-void compute_bitrev_table(
- int Fout,
- opus_int16 *f,
- const size_t fstride,
- int in_stride,
- opus_int16 * factors,
- const kiss_fft_state *st
- )
-{
- const int p=*factors++; /* the radix */
- const int m=*factors++; /* stage's fft length/p */
-
- /*printf ("fft %d %d %d %d %d %d\n", p*m, m, p, s2, fstride*in_stride, N);*/
- if (m==1)
- {
- int j;
- for (j=0;j<p;j++)
- {
- *f = Fout+j;
- f += fstride*in_stride;
- }
- } else {
- int j;
- for (j=0;j<p;j++)
- {
- compute_bitrev_table( Fout , f, fstride*p, in_stride, factors,st);
- f += fstride*in_stride;
- Fout += m;
- }
- }
-}
-
-/* facbuf is populated by p1,m1,p2,m2, ...
- where
- p[i] * m[i] = m[i-1]
- m0 = n */
-static
-int kf_factor(int n,opus_int16 * facbuf)
-{
- int p=4;
-
- /*factor out powers of 4, powers of 2, then any remaining primes */
- do {
- while (n % p) {
- switch (p) {
- case 4: p = 2; break;
- case 2: p = 3; break;
- default: p += 2; break;
- }
- if (p>32000 || (opus_int32)p*(opus_int32)p > n)
- p = n; /* no more factors, skip to end */
- }
- n /= p;
-#ifdef RADIX_TWO_ONLY
- if (p!=2 && p != 4)
-#else
- if (p>5)
-#endif
- {
- return 0;
- }
- *facbuf++ = p;
- *facbuf++ = n;
- } while (n > 1);
- return 1;
-}
-
-static void compute_twiddles(kiss_twiddle_cpx *twiddles, int nfft)
-{
- int i;
-#ifdef FIXED_POINT
- for (i=0;i<nfft;++i) {
- opus_val32 phase = -i;
- kf_cexp2(twiddles+i, DIV32(SHL32(phase,17),nfft));
- }
-#else
- for (i=0;i<nfft;++i) {
- const double pi=3.14159265358979323846264338327;
- double phase = ( -2*pi /nfft ) * i;
- kf_cexp(twiddles+i, phase );
- }
-#endif
-}
-
-/*
- *
- * Allocates all necessary storage space for the fft and ifft.
- * The return value is a contiguous block of memory. As such,
- * It can be freed with free().
- * */
-kiss_fft_state *opus_fft_alloc_twiddles(int nfft,void * mem,size_t * lenmem, const kiss_fft_state *base)
-{
- kiss_fft_state *st=NULL;
- size_t memneeded = sizeof(struct kiss_fft_state); /* twiddle factors*/
-
- if ( lenmem==NULL ) {
- st = ( kiss_fft_state*)KISS_FFT_MALLOC( memneeded );
- }else{
- if (mem != NULL && *lenmem >= memneeded)
- st = (kiss_fft_state*)mem;
- *lenmem = memneeded;
- }
- if (st) {
- opus_int16 *bitrev;
- kiss_twiddle_cpx *twiddles;
-
- st->nfft=nfft;
-#ifndef FIXED_POINT
- st->scale = 1.f/nfft;
-#endif
- if (base != NULL)
- {
- st->twiddles = base->twiddles;
- st->shift = 0;
- while (nfft<<st->shift != base->nfft && st->shift < 32)
- st->shift++;
- if (st->shift>=32)
- goto fail;
- } else {
- st->twiddles = twiddles = (kiss_twiddle_cpx*)KISS_FFT_MALLOC(sizeof(kiss_twiddle_cpx)*nfft);
- compute_twiddles(twiddles, nfft);
- st->shift = -1;
- }
- if (!kf_factor(nfft,st->factors))
- {
- goto fail;
- }
-
- /* bitrev */
- st->bitrev = bitrev = (opus_int16*)KISS_FFT_MALLOC(sizeof(opus_int16)*nfft);
- if (st->bitrev==NULL)
- goto fail;
- compute_bitrev_table(0, bitrev, 1,1, st->factors,st);
- }
- return st;
-fail:
- opus_fft_free(st);
- return NULL;
-}
-
-kiss_fft_state *opus_fft_alloc(int nfft,void * mem,size_t * lenmem )
-{
- return opus_fft_alloc_twiddles(nfft, mem, lenmem, NULL);
-}
-
-void opus_fft_free(const kiss_fft_state *cfg)
-{
- if (cfg)
- {
- opus_free((opus_int16*)cfg->bitrev);
- if (cfg->shift < 0)
- opus_free((kiss_twiddle_cpx*)cfg->twiddles);
- opus_free((kiss_fft_state*)cfg);
- }
-}
-
-#endif /* CUSTOM_MODES */
-
-void opus_fft(const kiss_fft_state *st,const kiss_fft_cpx *fin,kiss_fft_cpx *fout)
-{
- int m2, m;
- int p;
- int L;
- int fstride[MAXFACTORS];
- int i;
- int shift;
-
- /* st->shift can be -1 */
- shift = st->shift>0 ? st->shift : 0;
-
- celt_assert2 (fin != fout, "In-place FFT not supported");
- /* Bit-reverse the input */
- for (i=0;i<st->nfft;i++)
- {
- fout[st->bitrev[i]] = fin[i];
-#ifndef FIXED_POINT
- fout[st->bitrev[i]].r *= st->scale;
- fout[st->bitrev[i]].i *= st->scale;
-#endif
- }
-
- fstride[0] = 1;
- L=0;
- do {
- p = st->factors[2*L];
- m = st->factors[2*L+1];
- fstride[L+1] = fstride[L]*p;
- L++;
- } while(m!=1);
- m = st->factors[2*L-1];
- for (i=L-1;i>=0;i--)
- {
- if (i!=0)
- m2 = st->factors[2*i-1];
- else
- m2 = 1;
- switch (st->factors[2*i])
- {
- case 2:
- kf_bfly2(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- case 4:
- kf_bfly4(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- #ifndef RADIX_TWO_ONLY
- case 3:
- kf_bfly3(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- case 5:
- kf_bfly5(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- #endif
- }
- m = m2;
- }
-}
-
-void opus_ifft(const kiss_fft_state *st,const kiss_fft_cpx *fin,kiss_fft_cpx *fout)
-{
- int m2, m;
- int p;
- int L;
- int fstride[MAXFACTORS];
- int i;
- int shift;
-
- /* st->shift can be -1 */
- shift = st->shift>0 ? st->shift : 0;
- celt_assert2 (fin != fout, "In-place FFT not supported");
- /* Bit-reverse the input */
- for (i=0;i<st->nfft;i++)
- fout[st->bitrev[i]] = fin[i];
-
- fstride[0] = 1;
- L=0;
- do {
- p = st->factors[2*L];
- m = st->factors[2*L+1];
- fstride[L+1] = fstride[L]*p;
- L++;
- } while(m!=1);
- m = st->factors[2*L-1];
- for (i=L-1;i>=0;i--)
- {
- if (i!=0)
- m2 = st->factors[2*i-1];
- else
- m2 = 1;
- switch (st->factors[2*i])
- {
- case 2:
- ki_bfly2(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- case 4:
- ki_bfly4(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
-#ifndef RADIX_TWO_ONLY
- case 3:
- ki_bfly3(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
- case 5:
- ki_bfly5(fout,fstride[i]<<shift,st,m, fstride[i], m2);
- break;
-#endif
- }
- m = m2;
- }
-}
-