1381 lines
23 KiB
C
1381 lines
23 KiB
C
/* Notes from RFB:
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Looks like the user-level routines are:
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Real FFT
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void __ogg_fdrffti(int n, double *wsave, int *ifac)
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void __ogg_fdrfftf(int n,double *r,double *wsave,int *ifac)
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void __ogg_fdrfftb(int n, double *r, double *wsave, int *ifac)
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__ogg_fdrffti == initialization
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__ogg_fdrfftf == forward transform
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__ogg_fdrfftb == backward transform
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Parameters are
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n == length of sequence
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r == sequence to be transformed (input)
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== transformed sequence (output)
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wsave == work array of length 2n (allocated by caller)
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ifac == work array of length 15 (allocated by caller)
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Cosine quarter-wave FFT
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void __ogg_fdcosqi(int n, double *wsave, int *ifac)
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void __ogg_fdcosqf(int n,double *x,double *wsave,int *ifac)
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void __ogg_fdcosqb(int n,double *x,double *wsave,int *ifac)
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*/
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/********************************************************************
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* *
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* THIS FILE IS PART OF THE OggSQUISH SOFTWARE CODEC SOURCE CODE. *
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* *
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********************************************************************
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file: fft.c
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function: Fast discrete Fourier and cosine transforms and inverses
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author: Monty <xiphmont@mit.edu>
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modifications by: Monty
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last modification date: Jul 1 1996
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********************************************************************/
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/* These Fourier routines were originally based on the Fourier
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routines of the same names from the NETLIB bihar and fftpack
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fortran libraries developed by Paul N. Swarztrauber at the National
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Center for Atmospheric Research in Boulder, CO USA. They have been
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reimplemented in C and optimized in a few ways for OggSquish. */
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/* As the original fortran libraries are public domain, the C Fourier
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routines in this file are hereby released to the public domain as
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well. The C routines here produce output exactly equivalent to the
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original fortran routines. Of particular interest are the facts
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that (like the original fortran), these routines can work on
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arbitrary length vectors that need not be powers of two in
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length. */
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#include <math.h>
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#define STIN static
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static void drfti1(int n, double *wa, int *ifac){
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static int ntryh[4] = { 4,2,3,5 };
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static double tpi = 6.28318530717958647692528676655900577;
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double arg,argh,argld,fi;
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int ntry=0,i,j=-1;
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int k1, l1, l2, ib;
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int ld, ii, ip, is, nq, nr;
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int ido, ipm, nfm1;
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int nl=n;
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int nf=0;
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L101:
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j++;
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if (j < 4)
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ntry=ntryh[j];
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else
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ntry+=2;
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L104:
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nq=nl/ntry;
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nr=nl-ntry*nq;
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if (nr!=0) goto L101;
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nf++;
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ifac[nf+1]=ntry;
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nl=nq;
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if(ntry!=2)goto L107;
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if(nf==1)goto L107;
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for (i=1;i<nf;i++){
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ib=nf-i+1;
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ifac[ib+1]=ifac[ib];
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}
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ifac[2] = 2;
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L107:
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if(nl!=1)goto L104;
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ifac[0]=n;
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ifac[1]=nf;
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argh=tpi/n;
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is=0;
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nfm1=nf-1;
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l1=1;
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if(nfm1==0)return;
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for (k1=0;k1<nfm1;k1++){
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ip=ifac[k1+2];
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ld=0;
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l2=l1*ip;
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ido=n/l2;
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ipm=ip-1;
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for (j=0;j<ipm;j++){
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ld+=l1;
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i=is;
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argld=(double)ld*argh;
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fi=0.;
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for (ii=2;ii<ido;ii+=2){
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fi+=1.;
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arg=fi*argld;
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wa[i++]=cos(arg);
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wa[i++]=sin(arg);
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}
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is+=ido;
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}
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l1=l2;
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}
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}
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void __ogg_fdrffti(int n, double *wsave, int *ifac){
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if (n == 1) return;
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drfti1(n, wsave+n, ifac);
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}
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void __ogg_fdcosqi(int n, double *wsave, int *ifac){
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static double pih = 1.57079632679489661923132169163975;
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static int k;
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static double fk, dt;
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dt=pih/n;
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fk=0.;
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for(k=0;k<n;k++){
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fk+=1.;
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wsave[k] = cos(fk*dt);
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}
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__ogg_fdrffti(n, wsave+n,ifac);
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}
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STIN void dradf2(int ido,int l1,double *cc,double *ch,double *wa1){
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int i,k;
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double ti2,tr2;
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int t0,t1,t2,t3,t4,t5,t6;
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t1=0;
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t0=(t2=l1*ido);
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t3=ido<<1;
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for(k=0;k<l1;k++){
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ch[t1<<1]=cc[t1]+cc[t2];
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ch[(t1<<1)+t3-1]=cc[t1]-cc[t2];
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t1+=ido;
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t2+=ido;
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}
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if(ido<2)return;
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if(ido==2)goto L105;
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t1=0;
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t2=t0;
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for(k=0;k<l1;k++){
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t3=t2;
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t4=(t1<<1)+(ido<<1);
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t5=t1;
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t6=t1+t1;
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for(i=2;i<ido;i+=2){
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t3+=2;
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t4-=2;
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t5+=2;
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t6+=2;
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tr2=wa1[i-2]*cc[t3-1]+wa1[i-1]*cc[t3];
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ti2=wa1[i-2]*cc[t3]-wa1[i-1]*cc[t3-1];
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ch[t6]=cc[t5]+ti2;
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ch[t4]=ti2-cc[t5];
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ch[t6-1]=cc[t5-1]+tr2;
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ch[t4-1]=cc[t5-1]-tr2;
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}
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t1+=ido;
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t2+=ido;
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}
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if(ido%2==1)return;
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L105:
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t3=(t2=(t1=ido)-1);
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t2+=t0;
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for(k=0;k<l1;k++){
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ch[t1]=-cc[t2];
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ch[t1-1]=cc[t3];
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t1+=ido<<1;
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t2+=ido;
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t3+=ido;
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}
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}
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STIN void dradf4(int ido,int l1,double *cc,double *ch,double *wa1,
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double *wa2,double *wa3){
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static double hsqt2 = .70710678118654752440084436210485;
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int i,k,t0,t1,t2,t3,t4,t5,t6;
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double ci2,ci3,ci4,cr2,cr3,cr4,ti1,ti2,ti3,ti4,tr1,tr2,tr3,tr4;
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t0=l1*ido;
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t1=t0;
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t4=t1<<1;
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t2=t1+(t1<<1);
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t3=0;
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for(k=0;k<l1;k++){
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tr1=cc[t1]+cc[t2];
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tr2=cc[t3]+cc[t4];
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ch[t5=t3<<2]=tr1+tr2;
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ch[(ido<<2)+t5-1]=tr2-tr1;
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ch[(t5+=(ido<<1))-1]=cc[t3]-cc[t4];
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ch[t5]=cc[t2]-cc[t1];
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t1+=ido;
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t2+=ido;
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t3+=ido;
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t4+=ido;
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}
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if(ido<2)return;
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if(ido==2)goto L105;
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t1=0;
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for(k=0;k<l1;k++){
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t2=t1;
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t4=t1<<2;
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t5=(t6=ido<<1)+t4;
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for(i=2;i<ido;i+=2){
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t3=(t2+=2);
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t4+=2;
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t5-=2;
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t3+=t0;
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cr2=wa1[i-2]*cc[t3-1]+wa1[i-1]*cc[t3];
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ci2=wa1[i-2]*cc[t3]-wa1[i-1]*cc[t3-1];
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t3+=t0;
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cr3=wa2[i-2]*cc[t3-1]+wa2[i-1]*cc[t3];
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ci3=wa2[i-2]*cc[t3]-wa2[i-1]*cc[t3-1];
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t3+=t0;
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cr4=wa3[i-2]*cc[t3-1]+wa3[i-1]*cc[t3];
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ci4=wa3[i-2]*cc[t3]-wa3[i-1]*cc[t3-1];
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tr1=cr2+cr4;
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tr4=cr4-cr2;
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ti1=ci2+ci4;
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ti4=ci2-ci4;
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ti2=cc[t2]+ci3;
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ti3=cc[t2]-ci3;
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tr2=cc[t2-1]+cr3;
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tr3=cc[t2-1]-cr3;
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ch[t4-1]=tr1+tr2;
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ch[t4]=ti1+ti2;
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ch[t5-1]=tr3-ti4;
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ch[t5]=tr4-ti3;
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ch[t4+t6-1]=ti4+tr3;
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ch[t4+t6]=tr4+ti3;
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ch[t5+t6-1]=tr2-tr1;
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ch[t5+t6]=ti1-ti2;
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}
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t1+=ido;
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}
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if(ido%2==1)return;
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L105:
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t2=(t1=t0+ido-1)+(t0<<1);
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t3=ido<<2;
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t4=ido;
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t5=ido<<1;
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t6=ido;
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for(k=0;k<l1;k++){
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ti1=-hsqt2*(cc[t1]+cc[t2]);
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tr1=hsqt2*(cc[t1]-cc[t2]);
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ch[t4-1]=tr1+cc[t6-1];
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ch[t4+t5-1]=cc[t6-1]-tr1;
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ch[t4]=ti1-cc[t1+t0];
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ch[t4+t5]=ti1+cc[t1+t0];
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t1+=ido;
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t2+=ido;
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t4+=t3;
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t6+=ido;
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}
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}
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STIN void dradfg(int ido,int ip,int l1,int idl1,double *cc,double *c1,
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double *c2,double *ch,double *ch2,double *wa){
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static double tpi=6.28318530717958647692528676655900577;
|
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int idij,ipph,i,j,k,l,ic,ik,is;
|
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int t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10;
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double dc2,ai1,ai2,ar1,ar2,ds2;
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int nbd;
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double dcp,arg,dsp,ar1h,ar2h;
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int idp2,ipp2;
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arg=tpi/(double)ip;
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dcp=cos(arg);
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dsp=sin(arg);
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ipph=(ip+1)>>1;
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ipp2=ip;
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idp2=ido;
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nbd=(ido-1)>>1;
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t0=l1*ido;
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t10=ip*ido;
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if(ido==1)goto L119;
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for(ik=0;ik<idl1;ik++)ch2[ik]=c2[ik];
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t1=0;
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for(j=1;j<ip;j++){
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t1+=t0;
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t2=t1;
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for(k=0;k<l1;k++){
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ch[t2]=c1[t2];
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t2+=ido;
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}
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}
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|
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is=-ido;
|
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t1=0;
|
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if(nbd>l1){
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for(j=1;j<ip;j++){
|
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t1+=t0;
|
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is+=ido;
|
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t2= -ido+t1;
|
|
for(k=0;k<l1;k++){
|
|
idij=is-1;
|
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t2+=ido;
|
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t3=t2;
|
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for(i=2;i<ido;i+=2){
|
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idij+=2;
|
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t3+=2;
|
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ch[t3-1]=wa[idij-1]*c1[t3-1]+wa[idij]*c1[t3];
|
|
ch[t3]=wa[idij-1]*c1[t3]-wa[idij]*c1[t3-1];
|
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}
|
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}
|
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}
|
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}else{
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|
|
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for(j=1;j<ip;j++){
|
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is+=ido;
|
|
idij=is-1;
|
|
t1+=t0;
|
|
t2=t1;
|
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for(i=2;i<ido;i+=2){
|
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idij+=2;
|
|
t2+=2;
|
|
t3=t2;
|
|
for(k=0;k<l1;k++){
|
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ch[t3-1]=wa[idij-1]*c1[t3-1]+wa[idij]*c1[t3];
|
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ch[t3]=wa[idij-1]*c1[t3]-wa[idij]*c1[t3-1];
|
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t3+=ido;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
if(nbd<l1){
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
for(i=2;i<ido;i+=2){
|
|
t3+=2;
|
|
t4+=2;
|
|
t5=t3-ido;
|
|
t6=t4-ido;
|
|
for(k=0;k<l1;k++){
|
|
t5+=ido;
|
|
t6+=ido;
|
|
c1[t5-1]=ch[t5-1]+ch[t6-1];
|
|
c1[t6-1]=ch[t5]-ch[t6];
|
|
c1[t5]=ch[t5]+ch[t6];
|
|
c1[t6]=ch[t6-1]-ch[t5-1];
|
|
}
|
|
}
|
|
}
|
|
}else{
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
for(k=0;k<l1;k++){
|
|
t5=t3;
|
|
t6=t4;
|
|
for(i=2;i<ido;i+=2){
|
|
t5+=2;
|
|
t6+=2;
|
|
c1[t5-1]=ch[t5-1]+ch[t6-1];
|
|
c1[t6-1]=ch[t5]-ch[t6];
|
|
c1[t5]=ch[t5]+ch[t6];
|
|
c1[t6]=ch[t6-1]-ch[t5-1];
|
|
}
|
|
t3+=ido;
|
|
t4+=ido;
|
|
}
|
|
}
|
|
}
|
|
|
|
L119:
|
|
for(ik=0;ik<idl1;ik++)c2[ik]=ch2[ik];
|
|
|
|
t1=0;
|
|
t2=ipp2*idl1;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1-ido;
|
|
t4=t2-ido;
|
|
for(k=0;k<l1;k++){
|
|
t3+=ido;
|
|
t4+=ido;
|
|
c1[t3]=ch[t3]+ch[t4];
|
|
c1[t4]=ch[t4]-ch[t3];
|
|
}
|
|
}
|
|
|
|
ar1=1.;
|
|
ai1=0.;
|
|
t1=0;
|
|
t2=ipp2*idl1;
|
|
t3=(ip-1)*idl1;
|
|
for(l=1;l<ipph;l++){
|
|
t1+=idl1;
|
|
t2-=idl1;
|
|
ar1h=dcp*ar1-dsp*ai1;
|
|
ai1=dcp*ai1+dsp*ar1;
|
|
ar1=ar1h;
|
|
t4=t1;
|
|
t5=t2;
|
|
t6=t3;
|
|
t7=idl1;
|
|
|
|
for(ik=0;ik<idl1;ik++){
|
|
ch2[t4++]=c2[ik]+ar1*c2[t7++];
|
|
ch2[t5++]=ai1*c2[t6++];
|
|
}
|
|
|
|
dc2=ar1;
|
|
ds2=ai1;
|
|
ar2=ar1;
|
|
ai2=ai1;
|
|
|
|
t4=idl1;
|
|
t5=(ipp2-1)*idl1;
|
|
for(j=2;j<ipph;j++){
|
|
t4+=idl1;
|
|
t5-=idl1;
|
|
|
|
ar2h=dc2*ar2-ds2*ai2;
|
|
ai2=dc2*ai2+ds2*ar2;
|
|
ar2=ar2h;
|
|
|
|
t6=t1;
|
|
t7=t2;
|
|
t8=t4;
|
|
t9=t5;
|
|
for(ik=0;ik<idl1;ik++){
|
|
ch2[t6++]+=ar2*c2[t8++];
|
|
ch2[t7++]+=ai2*c2[t9++];
|
|
}
|
|
}
|
|
}
|
|
|
|
t1=0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=idl1;
|
|
t2=t1;
|
|
for(ik=0;ik<idl1;ik++)ch2[ik]+=c2[t2++];
|
|
}
|
|
|
|
if(ido<l1)goto L132;
|
|
|
|
t1=0;
|
|
t2=0;
|
|
for(k=0;k<l1;k++){
|
|
t3=t1;
|
|
t4=t2;
|
|
for(i=0;i<ido;i++)cc[t4++]=ch[t3++];
|
|
t1+=ido;
|
|
t2+=t10;
|
|
}
|
|
|
|
goto L135;
|
|
|
|
L132:
|
|
for(i=0;i<ido;i++){
|
|
t1=i;
|
|
t2=i;
|
|
for(k=0;k<l1;k++){
|
|
cc[t2]=ch[t1];
|
|
t1+=ido;
|
|
t2+=t10;
|
|
}
|
|
}
|
|
|
|
L135:
|
|
t1=0;
|
|
t2=ido<<1;
|
|
t3=0;
|
|
t4=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
|
|
t1+=t2;
|
|
t3+=t0;
|
|
t4-=t0;
|
|
|
|
t5=t1;
|
|
t6=t3;
|
|
t7=t4;
|
|
|
|
for(k=0;k<l1;k++){
|
|
cc[t5-1]=ch[t6];
|
|
cc[t5]=ch[t7];
|
|
t5+=t10;
|
|
t6+=ido;
|
|
t7+=ido;
|
|
}
|
|
}
|
|
|
|
if(ido==1)return;
|
|
if(nbd<l1)goto L141;
|
|
|
|
t1=-ido;
|
|
t3=0;
|
|
t4=0;
|
|
t5=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t2;
|
|
t3+=t2;
|
|
t4+=t0;
|
|
t5-=t0;
|
|
t6=t1;
|
|
t7=t3;
|
|
t8=t4;
|
|
t9=t5;
|
|
for(k=0;k<l1;k++){
|
|
for(i=2;i<ido;i+=2){
|
|
ic=idp2-i;
|
|
cc[i+t7-1]=ch[i+t8-1]+ch[i+t9-1];
|
|
cc[ic+t6-1]=ch[i+t8-1]-ch[i+t9-1];
|
|
cc[i+t7]=ch[i+t8]+ch[i+t9];
|
|
cc[ic+t6]=ch[i+t9]-ch[i+t8];
|
|
}
|
|
t6+=t10;
|
|
t7+=t10;
|
|
t8+=ido;
|
|
t9+=ido;
|
|
}
|
|
}
|
|
return;
|
|
|
|
L141:
|
|
|
|
t1=-ido;
|
|
t3=0;
|
|
t4=0;
|
|
t5=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t2;
|
|
t3+=t2;
|
|
t4+=t0;
|
|
t5-=t0;
|
|
for(i=2;i<ido;i+=2){
|
|
t6=idp2+t1-i;
|
|
t7=i+t3;
|
|
t8=i+t4;
|
|
t9=i+t5;
|
|
for(k=0;k<l1;k++){
|
|
cc[t7-1]=ch[t8-1]+ch[t9-1];
|
|
cc[t6-1]=ch[t8-1]-ch[t9-1];
|
|
cc[t7]=ch[t8]+ch[t9];
|
|
cc[t6]=ch[t9]-ch[t8];
|
|
t6+=t10;
|
|
t7+=t10;
|
|
t8+=ido;
|
|
t9+=ido;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
STIN void drftf1(int n,double *c,double *ch,double *wa,int *ifac){
|
|
int i,k1,l1,l2;
|
|
int na,kh,nf;
|
|
int ip,iw,ido,idl1,ix2,ix3;
|
|
|
|
nf=ifac[1];
|
|
na=1;
|
|
l2=n;
|
|
iw=n;
|
|
|
|
for(k1=0;k1<nf;k1++){
|
|
kh=nf-k1;
|
|
ip=ifac[kh+1];
|
|
l1=l2/ip;
|
|
ido=n/l2;
|
|
idl1=ido*l1;
|
|
iw-=(ip-1)*ido;
|
|
na=1-na;
|
|
|
|
if(ip!=4)goto L102;
|
|
|
|
ix2=iw+ido;
|
|
ix3=ix2+ido;
|
|
if(na!=0)
|
|
dradf4(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1);
|
|
else
|
|
dradf4(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1);
|
|
goto L110;
|
|
|
|
L102:
|
|
if(ip!=2)goto L104;
|
|
if(na!=0)goto L103;
|
|
|
|
dradf2(ido,l1,c,ch,wa+iw-1);
|
|
goto L110;
|
|
|
|
L103:
|
|
dradf2(ido,l1,ch,c,wa+iw-1);
|
|
goto L110;
|
|
|
|
L104:
|
|
if(ido==1)na=1-na;
|
|
if(na!=0)goto L109;
|
|
|
|
dradfg(ido,ip,l1,idl1,c,c,c,ch,ch,wa+iw-1);
|
|
na=1;
|
|
goto L110;
|
|
|
|
L109:
|
|
dradfg(ido,ip,l1,idl1,ch,ch,ch,c,c,wa+iw-1);
|
|
na=0;
|
|
|
|
L110:
|
|
l2=l1;
|
|
}
|
|
|
|
if(na==1)return;
|
|
|
|
for(i=0;i<n;i++)c[i]=ch[i];
|
|
}
|
|
|
|
void __ogg_fdrfftf(int n,double *r,double *wsave,int *ifac){
|
|
if(n==1)return;
|
|
drftf1(n,r,wsave,wsave+n,ifac);
|
|
}
|
|
|
|
STIN void dcsqf1(int n,double *x,double *w,double *xh,int *ifac){
|
|
int modn,i,k,kc;
|
|
int np2,ns2;
|
|
double xim1;
|
|
|
|
ns2=(n+1)>>1;
|
|
np2=n;
|
|
|
|
kc=np2;
|
|
for(k=1;k<ns2;k++){
|
|
kc--;
|
|
xh[k]=x[k]+x[kc];
|
|
xh[kc]=x[k]-x[kc];
|
|
}
|
|
|
|
modn=n%2;
|
|
if(modn==0)xh[ns2]=x[ns2]+x[ns2];
|
|
|
|
for(k=1;k<ns2;k++){
|
|
kc=np2-k;
|
|
x[k]=w[k-1]*xh[kc]+w[kc-1]*xh[k];
|
|
x[kc]=w[k-1]*xh[k]-w[kc-1]*xh[kc];
|
|
}
|
|
|
|
if(modn==0)x[ns2]=w[ns2-1]*xh[ns2];
|
|
|
|
__ogg_fdrfftf(n,x,xh,ifac);
|
|
|
|
for(i=2;i<n;i+=2){
|
|
xim1=x[i-1]-x[i];
|
|
x[i]=x[i-1]+x[i];
|
|
x[i-1]=xim1;
|
|
}
|
|
}
|
|
|
|
void __ogg_fdcosqf(int n,double *x,double *wsave,int *ifac){
|
|
static double sqrt2=1.4142135623730950488016887242097;
|
|
double tsqx;
|
|
|
|
switch(n){
|
|
case 0:case 1:
|
|
return;
|
|
case 2:
|
|
tsqx=sqrt2*x[1];
|
|
x[1]=x[0]-tsqx;
|
|
x[0]+=tsqx;
|
|
return;
|
|
default:
|
|
dcsqf1(n,x,wsave,wsave+n,ifac);
|
|
return;
|
|
}
|
|
}
|
|
|
|
STIN void dradb2(int ido,int l1,double *cc,double *ch,double *wa1){
|
|
int i,k,t0,t1,t2,t3,t4,t5,t6;
|
|
double ti2,tr2;
|
|
|
|
t0=l1*ido;
|
|
|
|
t1=0;
|
|
t2=0;
|
|
t3=(ido<<1)-1;
|
|
for(k=0;k<l1;k++){
|
|
ch[t1]=cc[t2]+cc[t3+t2];
|
|
ch[t1+t0]=cc[t2]-cc[t3+t2];
|
|
t2=(t1+=ido)<<1;
|
|
}
|
|
|
|
if(ido<2)return;
|
|
if(ido==2)goto L105;
|
|
|
|
t1=0;
|
|
t2=0;
|
|
for(k=0;k<l1;k++){
|
|
t3=t1;
|
|
t5=(t4=t2)+(ido<<1);
|
|
t6=t0+t1;
|
|
for(i=2;i<ido;i+=2){
|
|
t3+=2;
|
|
t4+=2;
|
|
t5-=2;
|
|
t6+=2;
|
|
ch[t3-1]=cc[t4-1]+cc[t5-1];
|
|
tr2=cc[t4-1]-cc[t5-1];
|
|
ch[t3]=cc[t4]-cc[t5];
|
|
ti2=cc[t4]+cc[t5];
|
|
ch[t6-1]=wa1[i-2]*tr2-wa1[i-1]*ti2;
|
|
ch[t6]=wa1[i-2]*ti2+wa1[i-1]*tr2;
|
|
}
|
|
t2=(t1+=ido)<<1;
|
|
}
|
|
|
|
if(ido%2==1)return;
|
|
|
|
L105:
|
|
t1=ido-1;
|
|
t2=ido-1;
|
|
for(k=0;k<l1;k++){
|
|
ch[t1]=cc[t2]+cc[t2];
|
|
ch[t1+t0]=-(cc[t2+1]+cc[t2+1]);
|
|
t1+=ido;
|
|
t2+=ido<<1;
|
|
}
|
|
}
|
|
|
|
STIN void dradb3(int ido,int l1,double *cc,double *ch,double *wa1,
|
|
double *wa2){
|
|
static double taur = -.5;
|
|
static double taui = .86602540378443864676372317075293618;
|
|
int i,k,t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10;
|
|
double ci2,ci3,di2,di3,cr2,cr3,dr2,dr3,ti2,tr2;
|
|
t0=l1*ido;
|
|
|
|
t1=0;
|
|
t2=t0<<1;
|
|
t3=ido<<1;
|
|
t4=ido+(ido<<1);
|
|
t5=0;
|
|
for(k=0;k<l1;k++){
|
|
tr2=cc[t3-1]+cc[t3-1];
|
|
cr2=cc[t5]+(taur*tr2);
|
|
ch[t1]=cc[t5]+tr2;
|
|
ci3=taui*(cc[t3]+cc[t3]);
|
|
ch[t1+t0]=cr2-ci3;
|
|
ch[t1+t2]=cr2+ci3;
|
|
t1+=ido;
|
|
t3+=t4;
|
|
t5+=t4;
|
|
}
|
|
|
|
if(ido==1)return;
|
|
|
|
t1=0;
|
|
t3=ido<<1;
|
|
for(k=0;k<l1;k++){
|
|
t7=t1+(t1<<1);
|
|
t6=(t5=t7+t3);
|
|
t8=t1;
|
|
t10=(t9=t1+t0)+t0;
|
|
|
|
for(i=2;i<ido;i+=2){
|
|
t5+=2;
|
|
t6-=2;
|
|
t7+=2;
|
|
t8+=2;
|
|
t9+=2;
|
|
t10+=2;
|
|
tr2=cc[t5-1]+cc[t6-1];
|
|
cr2=cc[t7-1]+(taur*tr2);
|
|
ch[t8-1]=cc[t7-1]+tr2;
|
|
ti2=cc[t5]-cc[t6];
|
|
ci2=cc[t7]+(taur*ti2);
|
|
ch[t8]=cc[t7]+ti2;
|
|
cr3=taui*(cc[t5-1]-cc[t6-1]);
|
|
ci3=taui*(cc[t5]+cc[t6]);
|
|
dr2=cr2-ci3;
|
|
dr3=cr2+ci3;
|
|
di2=ci2+cr3;
|
|
di3=ci2-cr3;
|
|
ch[t9-1]=wa1[i-2]*dr2-wa1[i-1]*di2;
|
|
ch[t9]=wa1[i-2]*di2+wa1[i-1]*dr2;
|
|
ch[t10-1]=wa2[i-2]*dr3-wa2[i-1]*di3;
|
|
ch[t10]=wa2[i-2]*di3+wa2[i-1]*dr3;
|
|
}
|
|
t1+=ido;
|
|
}
|
|
}
|
|
|
|
STIN void dradb4(int ido,int l1,double *cc,double *ch,double *wa1,
|
|
double *wa2,double *wa3){
|
|
static double sqrt2=1.4142135623730950488016887242097;
|
|
int i,k,t0,t1,t2,t3,t4,t5,t6,t7,t8;
|
|
double ci2,ci3,ci4,cr2,cr3,cr4,ti1,ti2,ti3,ti4,tr1,tr2,tr3,tr4;
|
|
t0=l1*ido;
|
|
|
|
t1=0;
|
|
t2=ido<<2;
|
|
t3=0;
|
|
t6=ido<<1;
|
|
for(k=0;k<l1;k++){
|
|
t4=t3+t6;
|
|
t5=t1;
|
|
tr3=cc[t4-1]+cc[t4-1];
|
|
tr4=cc[t4]+cc[t4];
|
|
tr1=cc[t3]-cc[(t4+=t6)-1];
|
|
tr2=cc[t3]+cc[t4-1];
|
|
ch[t5]=tr2+tr3;
|
|
ch[t5+=t0]=tr1-tr4;
|
|
ch[t5+=t0]=tr2-tr3;
|
|
ch[t5+=t0]=tr1+tr4;
|
|
t1+=ido;
|
|
t3+=t2;
|
|
}
|
|
|
|
if(ido<2)return;
|
|
if(ido==2)goto L105;
|
|
|
|
t1=0;
|
|
for(k=0;k<l1;k++){
|
|
t5=(t4=(t3=(t2=t1<<2)+t6))+t6;
|
|
t7=t1;
|
|
for(i=2;i<ido;i+=2){
|
|
t2+=2;
|
|
t3+=2;
|
|
t4-=2;
|
|
t5-=2;
|
|
t7+=2;
|
|
ti1=cc[t2]+cc[t5];
|
|
ti2=cc[t2]-cc[t5];
|
|
ti3=cc[t3]-cc[t4];
|
|
tr4=cc[t3]+cc[t4];
|
|
tr1=cc[t2-1]-cc[t5-1];
|
|
tr2=cc[t2-1]+cc[t5-1];
|
|
ti4=cc[t3-1]-cc[t4-1];
|
|
tr3=cc[t3-1]+cc[t4-1];
|
|
ch[t7-1]=tr2+tr3;
|
|
cr3=tr2-tr3;
|
|
ch[t7]=ti2+ti3;
|
|
ci3=ti2-ti3;
|
|
cr2=tr1-tr4;
|
|
cr4=tr1+tr4;
|
|
ci2=ti1+ti4;
|
|
ci4=ti1-ti4;
|
|
|
|
ch[(t8=t7+t0)-1]=wa1[i-2]*cr2-wa1[i-1]*ci2;
|
|
ch[t8]=wa1[i-2]*ci2+wa1[i-1]*cr2;
|
|
ch[(t8+=t0)-1]=wa2[i-2]*cr3-wa2[i-1]*ci3;
|
|
ch[t8]=wa2[i-2]*ci3+wa2[i-1]*cr3;
|
|
ch[(t8+=t0)-1]=wa3[i-2]*cr4-wa3[i-1]*ci4;
|
|
ch[t8]=wa3[i-2]*ci4+wa3[i-1]*cr4;
|
|
}
|
|
t1+=ido;
|
|
}
|
|
|
|
if(ido%2 == 1)return;
|
|
|
|
L105:
|
|
|
|
t1=ido;
|
|
t2=ido<<2;
|
|
t3=ido-1;
|
|
t4=ido+(ido<<1);
|
|
for(k=0;k<l1;k++){
|
|
t5=t3;
|
|
ti1=cc[t1]+cc[t4];
|
|
ti2=cc[t4]-cc[t1];
|
|
tr1=cc[t1-1]-cc[t4-1];
|
|
tr2=cc[t1-1]+cc[t4-1];
|
|
ch[t5]=tr2+tr2;
|
|
ch[t5+=t0]=sqrt2*(tr1-ti1);
|
|
ch[t5+=t0]=ti2+ti2;
|
|
ch[t5+=t0]=-sqrt2*(tr1+ti1);
|
|
|
|
t3+=ido;
|
|
t1+=t2;
|
|
t4+=t2;
|
|
}
|
|
}
|
|
|
|
STIN void dradbg(int ido,int ip,int l1,int idl1,double *cc,double *c1,
|
|
double *c2,double *ch,double *ch2,double *wa){
|
|
static double tpi=6.28318530717958647692528676655900577;
|
|
int idij,ipph,i,j,k,l,ik,is,t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,
|
|
t11,t12;
|
|
double dc2,ai1,ai2,ar1,ar2,ds2;
|
|
int nbd;
|
|
double dcp,arg,dsp,ar1h,ar2h;
|
|
int ipp2;
|
|
|
|
t10=ip*ido;
|
|
t0=l1*ido;
|
|
arg=tpi/(double)ip;
|
|
dcp=cos(arg);
|
|
dsp=sin(arg);
|
|
nbd=(ido-1)>>1;
|
|
ipp2=ip;
|
|
ipph=(ip+1)>>1;
|
|
if(ido<l1)goto L103;
|
|
|
|
t1=0;
|
|
t2=0;
|
|
for(k=0;k<l1;k++){
|
|
t3=t1;
|
|
t4=t2;
|
|
for(i=0;i<ido;i++){
|
|
ch[t3]=cc[t4];
|
|
t3++;
|
|
t4++;
|
|
}
|
|
t1+=ido;
|
|
t2+=t10;
|
|
}
|
|
goto L106;
|
|
|
|
L103:
|
|
t1=0;
|
|
for(i=0;i<ido;i++){
|
|
t2=t1;
|
|
t3=t1;
|
|
for(k=0;k<l1;k++){
|
|
ch[t2]=cc[t3];
|
|
t2+=ido;
|
|
t3+=t10;
|
|
}
|
|
t1++;
|
|
}
|
|
|
|
L106:
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
t7=(t5=ido<<1);
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
t6=t5;
|
|
for(k=0;k<l1;k++){
|
|
ch[t3]=cc[t6-1]+cc[t6-1];
|
|
ch[t4]=cc[t6]+cc[t6];
|
|
t3+=ido;
|
|
t4+=ido;
|
|
t6+=t10;
|
|
}
|
|
t5+=t7;
|
|
}
|
|
|
|
if (ido == 1)goto L116;
|
|
if(nbd<l1)goto L112;
|
|
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
t7=0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
|
|
t7+=(ido<<1);
|
|
t8=t7;
|
|
for(k=0;k<l1;k++){
|
|
t5=t3;
|
|
t6=t4;
|
|
t9=t8;
|
|
t11=t8;
|
|
for(i=2;i<ido;i+=2){
|
|
t5+=2;
|
|
t6+=2;
|
|
t9+=2;
|
|
t11-=2;
|
|
ch[t5-1]=cc[t9-1]+cc[t11-1];
|
|
ch[t6-1]=cc[t9-1]-cc[t11-1];
|
|
ch[t5]=cc[t9]-cc[t11];
|
|
ch[t6]=cc[t9]+cc[t11];
|
|
}
|
|
t3+=ido;
|
|
t4+=ido;
|
|
t8+=t10;
|
|
}
|
|
}
|
|
goto L116;
|
|
|
|
L112:
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
t7=0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
t7+=(ido<<1);
|
|
t8=t7;
|
|
t9=t7;
|
|
for(i=2;i<ido;i+=2){
|
|
t3+=2;
|
|
t4+=2;
|
|
t8+=2;
|
|
t9-=2;
|
|
t5=t3;
|
|
t6=t4;
|
|
t11=t8;
|
|
t12=t9;
|
|
for(k=0;k<l1;k++){
|
|
ch[t5-1]=cc[t11-1]+cc[t12-1];
|
|
ch[t6-1]=cc[t11-1]-cc[t12-1];
|
|
ch[t5]=cc[t11]-cc[t12];
|
|
ch[t6]=cc[t11]+cc[t12];
|
|
t5+=ido;
|
|
t6+=ido;
|
|
t11+=t10;
|
|
t12+=t10;
|
|
}
|
|
}
|
|
}
|
|
|
|
L116:
|
|
ar1=1.;
|
|
ai1=0.;
|
|
t1=0;
|
|
t9=(t2=ipp2*idl1);
|
|
t3=(ip-1)*idl1;
|
|
for(l=1;l<ipph;l++){
|
|
t1+=idl1;
|
|
t2-=idl1;
|
|
|
|
ar1h=dcp*ar1-dsp*ai1;
|
|
ai1=dcp*ai1+dsp*ar1;
|
|
ar1=ar1h;
|
|
t4=t1;
|
|
t5=t2;
|
|
t6=0;
|
|
t7=idl1;
|
|
t8=t3;
|
|
for(ik=0;ik<idl1;ik++){
|
|
c2[t4++]=ch2[t6++]+ar1*ch2[t7++];
|
|
c2[t5++]=ai1*ch2[t8++];
|
|
}
|
|
dc2=ar1;
|
|
ds2=ai1;
|
|
ar2=ar1;
|
|
ai2=ai1;
|
|
|
|
t6=idl1;
|
|
t7=t9-idl1;
|
|
for(j=2;j<ipph;j++){
|
|
t6+=idl1;
|
|
t7-=idl1;
|
|
ar2h=dc2*ar2-ds2*ai2;
|
|
ai2=dc2*ai2+ds2*ar2;
|
|
ar2=ar2h;
|
|
t4=t1;
|
|
t5=t2;
|
|
t11=t6;
|
|
t12=t7;
|
|
for(ik=0;ik<idl1;ik++){
|
|
c2[t4++]+=ar2*ch2[t11++];
|
|
c2[t5++]+=ai2*ch2[t12++];
|
|
}
|
|
}
|
|
}
|
|
|
|
t1=0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=idl1;
|
|
t2=t1;
|
|
for(ik=0;ik<idl1;ik++)ch2[ik]+=ch2[t2++];
|
|
}
|
|
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
for(k=0;k<l1;k++){
|
|
ch[t3]=c1[t3]-c1[t4];
|
|
ch[t4]=c1[t3]+c1[t4];
|
|
t3+=ido;
|
|
t4+=ido;
|
|
}
|
|
}
|
|
|
|
if(ido==1)goto L132;
|
|
if(nbd<l1)goto L128;
|
|
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
for(k=0;k<l1;k++){
|
|
t5=t3;
|
|
t6=t4;
|
|
for(i=2;i<ido;i+=2){
|
|
t5+=2;
|
|
t6+=2;
|
|
ch[t5-1]=c1[t5-1]-c1[t6];
|
|
ch[t6-1]=c1[t5-1]+c1[t6];
|
|
ch[t5]=c1[t5]+c1[t6-1];
|
|
ch[t6]=c1[t5]-c1[t6-1];
|
|
}
|
|
t3+=ido;
|
|
t4+=ido;
|
|
}
|
|
}
|
|
goto L132;
|
|
|
|
L128:
|
|
t1=0;
|
|
t2=ipp2*t0;
|
|
for(j=1;j<ipph;j++){
|
|
t1+=t0;
|
|
t2-=t0;
|
|
t3=t1;
|
|
t4=t2;
|
|
for(i=2;i<ido;i+=2){
|
|
t3+=2;
|
|
t4+=2;
|
|
t5=t3;
|
|
t6=t4;
|
|
for(k=0;k<l1;k++){
|
|
ch[t5-1]=c1[t5-1]-c1[t6];
|
|
ch[t6-1]=c1[t5-1]+c1[t6];
|
|
ch[t5]=c1[t5]+c1[t6-1];
|
|
ch[t6]=c1[t5]-c1[t6-1];
|
|
t5+=ido;
|
|
t6+=ido;
|
|
}
|
|
}
|
|
}
|
|
|
|
L132:
|
|
if(ido==1)return;
|
|
|
|
for(ik=0;ik<idl1;ik++)c2[ik]=ch2[ik];
|
|
|
|
t1=0;
|
|
for(j=1;j<ip;j++){
|
|
t2=(t1+=t0);
|
|
for(k=0;k<l1;k++){
|
|
c1[t2]=ch[t2];
|
|
t2+=ido;
|
|
}
|
|
}
|
|
|
|
if(nbd>l1)goto L139;
|
|
|
|
is= -ido-1;
|
|
t1=0;
|
|
for(j=1;j<ip;j++){
|
|
is+=ido;
|
|
t1+=t0;
|
|
idij=is;
|
|
t2=t1;
|
|
for(i=2;i<ido;i+=2){
|
|
t2+=2;
|
|
idij+=2;
|
|
t3=t2;
|
|
for(k=0;k<l1;k++){
|
|
c1[t3-1]=wa[idij-1]*ch[t3-1]-wa[idij]*ch[t3];
|
|
c1[t3]=wa[idij-1]*ch[t3]+wa[idij]*ch[t3-1];
|
|
t3+=ido;
|
|
}
|
|
}
|
|
}
|
|
return;
|
|
|
|
L139:
|
|
is= -ido-1;
|
|
t1=0;
|
|
for(j=1;j<ip;j++){
|
|
is+=ido;
|
|
t1+=t0;
|
|
t2=t1;
|
|
for(k=0;k<l1;k++){
|
|
idij=is;
|
|
t3=t2;
|
|
for(i=2;i<ido;i+=2){
|
|
idij+=2;
|
|
t3+=2;
|
|
c1[t3-1]=wa[idij-1]*ch[t3-1]-wa[idij]*ch[t3];
|
|
c1[t3]=wa[idij-1]*ch[t3]+wa[idij]*ch[t3-1];
|
|
}
|
|
t2+=ido;
|
|
}
|
|
}
|
|
}
|
|
|
|
STIN void drftb1(int n, double *c, double *ch, double *wa, int *ifac){
|
|
int i,k1,l1,l2;
|
|
int na;
|
|
int nf,ip,iw,ix2,ix3,ido,idl1;
|
|
|
|
nf=ifac[1];
|
|
na=0;
|
|
l1=1;
|
|
iw=1;
|
|
|
|
for(k1=0;k1<nf;k1++){
|
|
ip=ifac[k1 + 2];
|
|
l2=ip*l1;
|
|
ido=n/l2;
|
|
idl1=ido*l1;
|
|
if(ip!=4)goto L103;
|
|
ix2=iw+ido;
|
|
ix3=ix2+ido;
|
|
|
|
if(na!=0)
|
|
dradb4(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1);
|
|
else
|
|
dradb4(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1);
|
|
na=1-na;
|
|
goto L115;
|
|
|
|
L103:
|
|
if(ip!=2)goto L106;
|
|
|
|
if(na!=0)
|
|
dradb2(ido,l1,ch,c,wa+iw-1);
|
|
else
|
|
dradb2(ido,l1,c,ch,wa+iw-1);
|
|
na=1-na;
|
|
goto L115;
|
|
|
|
L106:
|
|
if(ip!=3)goto L109;
|
|
|
|
ix2=iw+ido;
|
|
if(na!=0)
|
|
dradb3(ido,l1,ch,c,wa+iw-1,wa+ix2-1);
|
|
else
|
|
dradb3(ido,l1,c,ch,wa+iw-1,wa+ix2-1);
|
|
na=1-na;
|
|
goto L115;
|
|
|
|
L109:
|
|
/* The radix five case can be translated later..... */
|
|
/* if(ip!=5)goto L112;
|
|
|
|
ix2=iw+ido;
|
|
ix3=ix2+ido;
|
|
ix4=ix3+ido;
|
|
if(na!=0)
|
|
dradb5(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1,wa+ix4-1);
|
|
else
|
|
dradb5(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1,wa+ix4-1);
|
|
na=1-na;
|
|
goto L115;
|
|
|
|
L112:*/
|
|
if(na!=0)
|
|
dradbg(ido,ip,l1,idl1,ch,ch,ch,c,c,wa+iw-1);
|
|
else
|
|
dradbg(ido,ip,l1,idl1,c,c,c,ch,ch,wa+iw-1);
|
|
if(ido==1)na=1-na;
|
|
|
|
L115:
|
|
l1=l2;
|
|
iw+=(ip-1)*ido;
|
|
}
|
|
|
|
if(na==0)return;
|
|
|
|
for(i=0;i<n;i++)c[i]=ch[i];
|
|
}
|
|
|
|
void __ogg_fdrfftb(int n, double *r, double *wsave, int *ifac){
|
|
if (n == 1)return;
|
|
drftb1(n, r, wsave, wsave+n, ifac);
|
|
}
|
|
|
|
STIN void dcsqb1(int n,double *x,double *w,double *xh,int *ifac){
|
|
int modn,i,k,kc;
|
|
int np2,ns2;
|
|
double xim1;
|
|
|
|
ns2=(n+1)>>1;
|
|
np2=n;
|
|
|
|
for(i=2;i<n;i+=2){
|
|
xim1=x[i-1]+x[i];
|
|
x[i]-=x[i-1];
|
|
x[i-1]=xim1;
|
|
}
|
|
|
|
x[0]+=x[0];
|
|
modn=n%2;
|
|
if(modn==0)x[n-1]+=x[n-1];
|
|
|
|
__ogg_fdrfftb(n,x,xh,ifac);
|
|
|
|
kc=np2;
|
|
for(k=1;k<ns2;k++){
|
|
kc--;
|
|
xh[k]=w[k-1]*x[kc]+w[kc-1]*x[k];
|
|
xh[kc]=w[k-1]*x[k]-w[kc-1]*x[kc];
|
|
}
|
|
|
|
if(modn==0)x[ns2]=w[ns2-1]*(x[ns2]+x[ns2]);
|
|
|
|
kc=np2;
|
|
for(k=1;k<ns2;k++){
|
|
kc--;
|
|
x[k]=xh[k]+xh[kc];
|
|
x[kc]=xh[k]-xh[kc];
|
|
}
|
|
x[0]+=x[0];
|
|
}
|
|
|
|
void __ogg_fdcosqb(int n,double *x,double *wsave,int *ifac){
|
|
static double tsqrt2 = 2.8284271247461900976033774484194;
|
|
double x1;
|
|
|
|
if(n<2){
|
|
x[0]*=4;
|
|
return;
|
|
}
|
|
if(n==2){
|
|
x1=(x[0]+x[1])*4;
|
|
x[1]=tsqrt2*(x[0]-x[1]);
|
|
x[0]=x1;
|
|
return;
|
|
}
|
|
|
|
dcsqb1(n,x,wsave,wsave+n,ifac);
|
|
}
|