* GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
* *
- * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
- * by the XIPHOPHORUS Company http://www.xiph.org/ *
+ * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
+ * by the Xiph.Org Foundation https://xiph.org/ *
* *
********************************************************************
- function: PCM data envelope analysis
- last mod: $Id: envelope.c,v 1.42 2002/03/17 19:50:47 xiphmont Exp $
+ function: PCM data envelope analysis
********************************************************************/
codec_setup_info *ci=vi->codec_setup;
vorbis_info_psy_global *gi=&ci->psy_g_param;
int ch=vi->channels;
- int i;
- int n=e->winlength=ci->blocksizes[0];
- e->searchstep=ci->blocksizes[0]/VE_DIV; /* not random */
+ int i,j;
+ int n=e->winlength=128;
+ e->searchstep=64; /* not random */
- e->minenergy=fromdB(gi->preecho_minenergy);
+ e->minenergy=gi->preecho_minenergy;
e->ch=ch;
e->storage=128;
e->cursor=ci->blocksizes[1]/2;
mdct_init(&e->mdct,n);
for(i=0;i<n;i++){
- e->mdct_win[i]=sin((i+.5)/n*M_PI);
+ e->mdct_win[i]=sin(i/(n-1.)*M_PI);
e->mdct_win[i]*=e->mdct_win[i];
}
- /* overlapping bands, assuming 22050 (which is not always true, but
- to Hell with that) */
- /* 2(1.3-3) 4(2.6-6) 8(5.3-12) 16(10.6-18) */
-
- e->band[0].begin=rint(1300.f/22050.f*n/4.f)*2.f;
- e->band[0].end=rint(3000.f/22050.f*n/4.f)*2.f-e->band[0].begin;
- e->band[1].begin=rint(2600.f/22050.f*n/4.f)*2.f;
- e->band[1].end=rint(6000.f/22050.f*n/4.f)*2.f-e->band[1].begin;
- e->band[2].begin=rint(5300.f/22050.f*n/4.f)*2.f;
- e->band[2].end=rint(12000.f/22050.f*n/4.f)*2.f-e->band[2].begin;
- e->band[3].begin=rint(10600.f/22050.f*n/4.f)*2.f;
- e->band[3].end=rint(18000.f/22050.f*n/4.f)*2.f-e->band[3].begin;
-
- e->band[0].window=_ogg_malloc((e->band[0].end)*sizeof(*e->band[0].window));
- e->band[1].window=_ogg_malloc((e->band[1].end)*sizeof(*e->band[1].window));
- e->band[2].window=_ogg_malloc((e->band[2].end)*sizeof(*e->band[2].window));
- e->band[3].window=_ogg_malloc((e->band[3].end)*sizeof(*e->band[3].window));
-
- n=e->band[0].end;
- for(i=0;i<n;i++)
- e->band[0].window[i]=sin((i+.5)/n*M_PI);
- n=e->band[1].end;
- for(i=0;i<n;i++)
- e->band[1].window[i]=sin((i+.5)/n*M_PI);
- n=e->band[2].end;
- for(i=0;i<n;i++)
- e->band[2].window[i]=sin((i+.5)/n*M_PI);
- n=e->band[3].end;
- for(i=0;i<n;i++)
- e->band[3].window[i]=sin((i+.5)/n*M_PI);
-
+ /* magic follows */
+ e->band[0].begin=2; e->band[0].end=4;
+ e->band[1].begin=4; e->band[1].end=5;
+ e->band[2].begin=6; e->band[2].end=6;
+ e->band[3].begin=9; e->band[3].end=8;
+ e->band[4].begin=13; e->band[4].end=8;
+ e->band[5].begin=17; e->band[5].end=8;
+ e->band[6].begin=22; e->band[6].end=8;
+
+ for(j=0;j<VE_BANDS;j++){
+ n=e->band[j].end;
+ e->band[j].window=_ogg_malloc(n*sizeof(*e->band[0].window));
+ for(i=0;i<n;i++){
+ e->band[j].window[i]=sin((i+.5)/n*M_PI);
+ e->band[j].total+=e->band[j].window[i];
+ }
+ e->band[j].total=1./e->band[j].total;
+ }
+
e->filter=_ogg_calloc(VE_BANDS*ch,sizeof(*e->filter));
e->mark=_ogg_calloc(e->storage,sizeof(*e->mark));
-
}
void _ve_envelope_clear(envelope_lookup *e){
/* fairly straight threshhold-by-band based until we find something
that works better and isn't patented. */
-static int seq2=0;
+
static int _ve_amp(envelope_lookup *ve,
- vorbis_info_psy_global *gi,
- float *data,
- envelope_band *bands,
- envelope_filter_state *filters,
- long pos){
+ vorbis_info_psy_global *gi,
+ float *data,
+ envelope_band *bands,
+ envelope_filter_state *filters){
long n=ve->winlength;
int ret=0;
long i,j;
+ float decay;
/* we want to have a 'minimum bar' for energy, else we're just
basing blocks on quantization noise that outweighs the signal
itself (for low power signals) */
- float minV=ve->minenergy,acc[VE_BANDS];
+ float minV=ve->minenergy;
float *vec=alloca(n*sizeof(*vec));
- memset(acc,0,sizeof(acc));
-
+
+ /* stretch is used to gradually lengthen the number of windows
+ considered prevoius-to-potential-trigger */
+ int stretch=max(VE_MINSTRETCH,ve->stretch/2);
+ float penalty=gi->stretch_penalty-(ve->stretch/2-VE_MINSTRETCH);
+ if(penalty<0.f)penalty=0.f;
+ if(penalty>gi->stretch_penalty)penalty=gi->stretch_penalty;
+
+ /*_analysis_output_always("lpcm",seq2,data,n,0,0,
+ totalshift+pos*ve->searchstep);*/
+
/* window and transform */
for(i=0;i<n;i++)
vec[i]=data[i]*ve->mdct_win[i];
mdct_forward(&ve->mdct,vec,vec);
- /* accumulate amplitude by band */
- for(j=0;j<VE_BANDS;j++){
- for(i=0;i<bands[j].end;i++){
- float val=vec[i+bands[j].begin];
- acc[j]+=val*val*bands[j].window[i];
+ /*_analysis_output_always("mdct",seq2,vec,n/2,0,1,0); */
+
+ /* near-DC spreading function; this has nothing to do with
+ psychoacoustics, just sidelobe leakage and window size */
+ {
+ float temp=vec[0]*vec[0]+.7*vec[1]*vec[1]+.2*vec[2]*vec[2];
+ int ptr=filters->nearptr;
+
+ /* the accumulation is regularly refreshed from scratch to avoid
+ floating point creep */
+ if(ptr==0){
+ decay=filters->nearDC_acc=filters->nearDC_partialacc+temp;
+ filters->nearDC_partialacc=temp;
+ }else{
+ decay=filters->nearDC_acc+=temp;
+ filters->nearDC_partialacc+=temp;
}
- acc[j]/=i*.707f;
- if(acc[j]<minV*minV)acc[j]=minV*minV;
- acc[j]=todB(acc+j);
- }
+ filters->nearDC_acc-=filters->nearDC[ptr];
+ filters->nearDC[ptr]=temp;
- /* convert amplitude to delta */
- for(j=0;j<VE_BANDS;j++){
- float val=acc[j]-filters[j].ampbuf[filters[j].ampptr];
- filters[j].ampbuf[filters[j].ampptr]=acc[j];
- acc[j]=val;
- filters[j].ampptr++;
- if(filters[j].ampptr>=VE_DIV)filters[j].ampptr=0;
+ decay*=(1./(VE_NEARDC+1));
+ filters->nearptr++;
+ if(filters->nearptr>=VE_NEARDC)filters->nearptr=0;
+ decay=todB(&decay)*.5-15.f;
}
- /* convolve deltas to threshhold values */
- for(j=0;j<VE_BANDS;j++){
- float *buf=filters[j].delbuf;
- float val=.14*buf[0]+.14*buf[1]+.72*acc[j];
- buf[0]=buf[1];buf[1]=acc[j];
- acc[j]=val;
+ /* perform spreading and limiting, also smooth the spectrum. yes,
+ the MDCT results in all real coefficients, but it still *behaves*
+ like real/imaginary pairs */
+ for(i=0;i<n/2;i+=2){
+ float val=vec[i]*vec[i]+vec[i+1]*vec[i+1];
+ val=todB(&val)*.5f;
+ if(val<decay)val=decay;
+ if(val<minV)val=minV;
+ vec[i>>1]=val;
+ decay-=8.;
}
- /* look at local min/max */
+ /*_analysis_output_always("spread",seq2++,vec,n/4,0,0,0);*/
+
+ /* perform preecho/postecho triggering by band */
for(j=0;j<VE_BANDS;j++){
- float *buf=filters[j].convbuf;
- if(buf[1]>gi->preecho_thresh[j] && buf[0]<buf[1] && acc[j]<buf[1])ret=1;
- if(buf[1]<gi->postecho_thresh[j] && buf[0]>buf[1] && acc[j]>buf[1])ret=1;
- buf[0]=buf[1];buf[1]=acc[j];
+ float acc=0.;
+ float valmax,valmin;
+
+ /* accumulate amplitude */
+ for(i=0;i<bands[j].end;i++)
+ acc+=vec[i+bands[j].begin]*bands[j].window[i];
+
+ acc*=bands[j].total;
+
+ /* convert amplitude to delta */
+ {
+ int p,this=filters[j].ampptr;
+ float postmax,postmin,premax=-99999.f,premin=99999.f;
+
+ p=this;
+ p--;
+ if(p<0)p+=VE_AMP;
+ postmax=max(acc,filters[j].ampbuf[p]);
+ postmin=min(acc,filters[j].ampbuf[p]);
+
+ for(i=0;i<stretch;i++){
+ p--;
+ if(p<0)p+=VE_AMP;
+ premax=max(premax,filters[j].ampbuf[p]);
+ premin=min(premin,filters[j].ampbuf[p]);
+ }
+
+ valmin=postmin-premin;
+ valmax=postmax-premax;
+
+ /*filters[j].markers[pos]=valmax;*/
+ filters[j].ampbuf[this]=acc;
+ filters[j].ampptr++;
+ if(filters[j].ampptr>=VE_AMP)filters[j].ampptr=0;
+ }
+
+ /* look at min/max, decide trigger */
+ if(valmax>gi->preecho_thresh[j]+penalty){
+ ret|=1;
+ ret|=4;
+ }
+ if(valmin<gi->postecho_thresh[j]-penalty)ret|=2;
}
+
return(ret);
}
+#if 0
static int seq=0;
+static ogg_int64_t totalshift=-1024;
+#endif
+
long _ve_envelope_search(vorbis_dsp_state *v){
vorbis_info *vi=v->vi;
codec_setup_info *ci=vi->codec_setup;
vorbis_info_psy_global *gi=&ci->psy_g_param;
- envelope_lookup *ve=((backend_lookup_state *)(v->backend_state))->ve;
+ envelope_lookup *ve=((private_state *)(v->backend_state))->ve;
long i,j;
int first=ve->current/ve->searchstep;
- int last=v->pcm_current/ve->searchstep-VE_DIV;
+ int last=v->pcm_current/ve->searchstep-VE_WIN;
if(first<0)first=0;
/* make sure we have enough storage to match the PCM */
- if(last>ve->storage){
- ve->storage=last;
+ if(last+VE_WIN+VE_POST>ve->storage){
+ ve->storage=last+VE_WIN+VE_POST; /* be sure */
ve->mark=_ogg_realloc(ve->mark,ve->storage*sizeof(*ve->mark));
}
for(j=first;j<last;j++){
int ret=0;
+
+ ve->stretch++;
+ if(ve->stretch>VE_MAXSTRETCH*2)
+ ve->stretch=VE_MAXSTRETCH*2;
+
for(i=0;i<ve->ch;i++){
- float *pcm=v->pcm[i]+ve->searchstep*(j+1);
- ret|=_ve_amp(ve,gi,pcm,ve->band,ve->filter+i*VE_BANDS,j);
+ float *pcm=v->pcm[i]+ve->searchstep*(j);
+ ret|=_ve_amp(ve,gi,pcm,ve->band,ve->filter+i*VE_BANDS);
+ }
+
+ ve->mark[j+VE_POST]=0;
+ if(ret&1){
+ ve->mark[j]=1;
+ ve->mark[j+1]=1;
+ }
+
+ if(ret&2){
+ ve->mark[j]=1;
+ if(j>0)ve->mark[j-1]=1;
}
- /* the mark delay is one searchstep because of min/max finder */
- ve->mark[j]=ret;
+
+ if(ret&4)ve->stretch=-1;
}
ve->current=last*ve->searchstep;
ci->blocksizes[v->W]/4+
ci->blocksizes[1]/2+
ci->blocksizes[0]/4;
-
+
j=ve->cursor;
-
- while(j<ve->current){
+
+ while(j<ve->current-(ve->searchstep)){/* account for postecho
+ working back one window */
if(j>=testW)return(1);
- if(ve->mark[j/ve->searchstep]){
- if(j>centerW){
- ve->curmark=j;
+ ve->cursor=j;
- if(j>=testW)return(1);
- return(0);
- }
+ if(ve->mark[j/ve->searchstep]){
+ if(j>centerW){
+
+#if 0
+ if(j>ve->curmark){
+ float *marker=alloca(v->pcm_current*sizeof(*marker));
+ int l,m;
+ memset(marker,0,sizeof(*marker)*v->pcm_current);
+ fprintf(stderr,"mark! seq=%d, cursor:%fs time:%fs\n",
+ seq,
+ (totalshift+ve->cursor)/44100.,
+ (totalshift+j)/44100.);
+ _analysis_output_always("pcmL",seq,v->pcm[0],v->pcm_current,0,0,totalshift);
+ _analysis_output_always("pcmR",seq,v->pcm[1],v->pcm_current,0,0,totalshift);
+
+ _analysis_output_always("markL",seq,v->pcm[0],j,0,0,totalshift);
+ _analysis_output_always("markR",seq,v->pcm[1],j,0,0,totalshift);
+
+ for(m=0;m<VE_BANDS;m++){
+ char buf[80];
+ sprintf(buf,"delL%d",m);
+ for(l=0;l<last;l++)marker[l*ve->searchstep]=ve->filter[m].markers[l]*.1;
+ _analysis_output_always(buf,seq,marker,v->pcm_current,0,0,totalshift);
+ }
+
+ for(m=0;m<VE_BANDS;m++){
+ char buf[80];
+ sprintf(buf,"delR%d",m);
+ for(l=0;l<last;l++)marker[l*ve->searchstep]=ve->filter[m+VE_BANDS].markers[l]*.1;
+ _analysis_output_always(buf,seq,marker,v->pcm_current,0,0,totalshift);
+ }
+
+ for(l=0;l<last;l++)marker[l*ve->searchstep]=ve->mark[l]*.4;
+ _analysis_output_always("mark",seq,marker,v->pcm_current,0,0,totalshift);
+
+
+ seq++;
+
+ }
+#endif
+
+ ve->curmark=j;
+ if(j>=testW)return(1);
+ return(0);
+ }
}
j+=ve->searchstep;
- ve->cursor=j;
}
}
-
+
return(-1);
}
int _ve_envelope_mark(vorbis_dsp_state *v){
- envelope_lookup *ve=((backend_lookup_state *)(v->backend_state))->ve;
+ envelope_lookup *ve=((private_state *)(v->backend_state))->ve;
vorbis_info *vi=v->vi;
codec_setup_info *ci=vi->codec_setup;
long centerW=v->centerW;
}
void _ve_envelope_shift(envelope_lookup *e,long shift){
- int smallsize=e->current/e->searchstep;
+ int smallsize=e->current/e->searchstep+VE_POST; /* adjust for placing marks
+ ahead of ve->current */
int smallshift=shift/e->searchstep;
- int i;
memmove(e->mark,e->mark+smallshift,(smallsize-smallshift)*sizeof(*e->mark));
+#if 0
+ for(i=0;i<VE_BANDS*e->ch;i++)
+ memmove(e->filter[i].markers,
+ e->filter[i].markers+smallshift,
+ (1024-smallshift)*sizeof(*(*e->filter).markers));
+ totalshift+=shift;
+#endif
+
e->current-=shift;
if(e->curmark>=0)
e->curmark-=shift;
e->cursor-=shift;
}
-
-