1 /********************************************************************
2  *                                                                  *
3  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
4  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
5  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
6  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
7  *                                                                  *
8  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2010             *
9  * by the Xiph.Org Foundation http://www.xiph.org/                  *
10  *                                                                  *
11  ********************************************************************
12 
13  function: psychoacoustics not including preecho
14  last mod: $Id: psy.c 17077 2010-03-26 06:22:19Z xiphmont $
15 
16  ********************************************************************/
17 
18 #include <stdlib.h>
19 #include <math.h>
20 #include <string.h>
21 #include "vorbis/codec.h"
22 #include "codec_internal.h"
23 
24 #include "masking.h"
25 #include "psy.h"
26 #include "os.h"
27 #include "lpc.h"
28 #include "smallft.h"
29 #include "scales.h"
30 #include "misc.h"
31 
32 #define NEGINF -9999.f
33 static const double stereo_threshholds[]={0.0, .5, 1.0, 1.5, 2.5, 4.5, 8.5, 16.5, 9e10};
34 static const double stereo_threshholds_limited[]={0.0, .5, 1.0, 1.5, 2.0, 2.5, 4.5, 8.5, 9e10};
35 
_vp_global_look(vorbis_info * vi)36 vorbis_look_psy_global *_vp_global_look(vorbis_info *vi){
37   codec_setup_info *ci=vi->codec_setup;
38   vorbis_info_psy_global *gi=&ci->psy_g_param;
39   vorbis_look_psy_global *look=_ogg_calloc(1,sizeof(*look));
40 
41   look->channels=vi->channels;
42 
43   look->ampmax=-9999.;
44   look->gi=gi;
45   return(look);
46 }
47 
_vp_global_free(vorbis_look_psy_global * look)48 void _vp_global_free(vorbis_look_psy_global *look){
49   if(look){
50     memset(look,0,sizeof(*look));
51     _ogg_free(look);
52   }
53 }
54 
_vi_gpsy_free(vorbis_info_psy_global * i)55 void _vi_gpsy_free(vorbis_info_psy_global *i){
56   if(i){
57     memset(i,0,sizeof(*i));
58     _ogg_free(i);
59   }
60 }
61 
_vi_psy_free(vorbis_info_psy * i)62 void _vi_psy_free(vorbis_info_psy *i){
63   if(i){
64     memset(i,0,sizeof(*i));
65     _ogg_free(i);
66   }
67 }
68 
min_curve(float * c,float * c2)69 static void min_curve(float *c,
70                        float *c2){
71   int i;
72   for(i=0;i<EHMER_MAX;i++)if(c2[i]<c[i])c[i]=c2[i];
73 }
max_curve(float * c,float * c2)74 static void max_curve(float *c,
75                        float *c2){
76   int i;
77   for(i=0;i<EHMER_MAX;i++)if(c2[i]>c[i])c[i]=c2[i];
78 }
79 
attenuate_curve(float * c,float att)80 static void attenuate_curve(float *c,float att){
81   int i;
82   for(i=0;i<EHMER_MAX;i++)
83     c[i]+=att;
84 }
85 
setup_tone_curves(float curveatt_dB[P_BANDS],float binHz,int n,float center_boost,float center_decay_rate)86 static float ***setup_tone_curves(float curveatt_dB[P_BANDS],float binHz,int n,
87                                   float center_boost, float center_decay_rate){
88   int i,j,k,m;
89   float ath[EHMER_MAX];
90   float workc[P_BANDS][P_LEVELS][EHMER_MAX];
91   float athc[P_LEVELS][EHMER_MAX];
92   float *brute_buffer=alloca(n*sizeof(*brute_buffer));
93 
94   float ***ret=_ogg_malloc(sizeof(*ret)*P_BANDS);
95 
96   memset(workc,0,sizeof(workc));
97 
98   for(i=0;i<P_BANDS;i++){
99     /* we add back in the ATH to avoid low level curves falling off to
100        -infinity and unnecessarily cutting off high level curves in the
101        curve limiting (last step). */
102 
103     /* A half-band's settings must be valid over the whole band, and
104        it's better to mask too little than too much */
105     int ath_offset=i*4;
106     for(j=0;j<EHMER_MAX;j++){
107       float min=999.;
108       for(k=0;k<4;k++)
109         if(j+k+ath_offset<MAX_ATH){
110           if(min>ATH[j+k+ath_offset])min=ATH[j+k+ath_offset];
111         }else{
112           if(min>ATH[MAX_ATH-1])min=ATH[MAX_ATH-1];
113         }
114       ath[j]=min;
115     }
116 
117     /* copy curves into working space, replicate the 50dB curve to 30
118        and 40, replicate the 100dB curve to 110 */
119     for(j=0;j<6;j++)
120       memcpy(workc[i][j+2],tonemasks[i][j],EHMER_MAX*sizeof(*tonemasks[i][j]));
121     memcpy(workc[i][0],tonemasks[i][0],EHMER_MAX*sizeof(*tonemasks[i][0]));
122     memcpy(workc[i][1],tonemasks[i][0],EHMER_MAX*sizeof(*tonemasks[i][0]));
123 
124     /* apply centered curve boost/decay */
125     for(j=0;j<P_LEVELS;j++){
126       for(k=0;k<EHMER_MAX;k++){
127         float adj=center_boost+abs(EHMER_OFFSET-k)*center_decay_rate;
128         if(adj<0. && center_boost>0)adj=0.;
129         if(adj>0. && center_boost<0)adj=0.;
130         workc[i][j][k]+=adj;
131       }
132     }
133 
134     /* normalize curves so the driving amplitude is 0dB */
135     /* make temp curves with the ATH overlayed */
136     for(j=0;j<P_LEVELS;j++){
137       attenuate_curve(workc[i][j],curveatt_dB[i]+100.-(j<2?2:j)*10.-P_LEVEL_0);
138       memcpy(athc[j],ath,EHMER_MAX*sizeof(**athc));
139       attenuate_curve(athc[j],+100.-j*10.f-P_LEVEL_0);
140       max_curve(athc[j],workc[i][j]);
141     }
142 
143     /* Now limit the louder curves.
144 
145        the idea is this: We don't know what the playback attenuation
146        will be; 0dB SL moves every time the user twiddles the volume
147        knob. So that means we have to use a single 'most pessimal' curve
148        for all masking amplitudes, right?  Wrong.  The *loudest* sound
149        can be in (we assume) a range of ...+100dB] SL.  However, sounds
150        20dB down will be in a range ...+80], 40dB down is from ...+60],
151        etc... */
152 
153     for(j=1;j<P_LEVELS;j++){
154       min_curve(athc[j],athc[j-1]);
155       min_curve(workc[i][j],athc[j]);
156     }
157   }
158 
159   for(i=0;i<P_BANDS;i++){
160     int hi_curve,lo_curve,bin;
161     ret[i]=_ogg_malloc(sizeof(**ret)*P_LEVELS);
162 
163     /* low frequency curves are measured with greater resolution than
164        the MDCT/FFT will actually give us; we want the curve applied
165        to the tone data to be pessimistic and thus apply the minimum
166        masking possible for a given bin.  That means that a single bin
167        could span more than one octave and that the curve will be a
168        composite of multiple octaves.  It also may mean that a single
169        bin may span > an eighth of an octave and that the eighth
170        octave values may also be composited. */
171 
172     /* which octave curves will we be compositing? */
173     bin=floor(fromOC(i*.5)/binHz);
174     lo_curve=  ceil(toOC(bin*binHz+1)*2);
175     hi_curve=  floor(toOC((bin+1)*binHz)*2);
176     if(lo_curve>i)lo_curve=i;
177     if(lo_curve<0)lo_curve=0;
178     if(hi_curve>=P_BANDS)hi_curve=P_BANDS-1;
179 
180     for(m=0;m<P_LEVELS;m++){
181       ret[i][m]=_ogg_malloc(sizeof(***ret)*(EHMER_MAX+2));
182 
183       for(j=0;j<n;j++)brute_buffer[j]=999.;
184 
185       /* render the curve into bins, then pull values back into curve.
186          The point is that any inherent subsampling aliasing results in
187          a safe minimum */
188       for(k=lo_curve;k<=hi_curve;k++){
189         int l=0;
190 
191         for(j=0;j<EHMER_MAX;j++){
192           int lo_bin= fromOC(j*.125+k*.5-2.0625)/binHz;
193           int hi_bin= fromOC(j*.125+k*.5-1.9375)/binHz+1;
194 
195           if(lo_bin<0)lo_bin=0;
196           if(lo_bin>n)lo_bin=n;
197           if(lo_bin<l)l=lo_bin;
198           if(hi_bin<0)hi_bin=0;
199           if(hi_bin>n)hi_bin=n;
200 
201           for(;l<hi_bin && l<n;l++)
202             if(brute_buffer[l]>workc[k][m][j])
203               brute_buffer[l]=workc[k][m][j];
204         }
205 
206         for(;l<n;l++)
207           if(brute_buffer[l]>workc[k][m][EHMER_MAX-1])
208             brute_buffer[l]=workc[k][m][EHMER_MAX-1];
209 
210       }
211 
212       /* be equally paranoid about being valid up to next half ocatve */
213       if(i+1<P_BANDS){
214         int l=0;
215         k=i+1;
216         for(j=0;j<EHMER_MAX;j++){
217           int lo_bin= fromOC(j*.125+i*.5-2.0625)/binHz;
218           int hi_bin= fromOC(j*.125+i*.5-1.9375)/binHz+1;
219 
220           if(lo_bin<0)lo_bin=0;
221           if(lo_bin>n)lo_bin=n;
222           if(lo_bin<l)l=lo_bin;
223           if(hi_bin<0)hi_bin=0;
224           if(hi_bin>n)hi_bin=n;
225 
226           for(;l<hi_bin && l<n;l++)
227             if(brute_buffer[l]>workc[k][m][j])
228               brute_buffer[l]=workc[k][m][j];
229         }
230 
231         for(;l<n;l++)
232           if(brute_buffer[l]>workc[k][m][EHMER_MAX-1])
233             brute_buffer[l]=workc[k][m][EHMER_MAX-1];
234 
235       }
236 
237 
238       for(j=0;j<EHMER_MAX;j++){
239         int bin=fromOC(j*.125+i*.5-2.)/binHz;
240         if(bin<0){
241           ret[i][m][j+2]=-999.;
242         }else{
243           if(bin>=n){
244             ret[i][m][j+2]=-999.;
245           }else{
246             ret[i][m][j+2]=brute_buffer[bin];
247           }
248         }
249       }
250 
251       /* add fenceposts */
252       for(j=0;j<EHMER_OFFSET;j++)
253         if(ret[i][m][j+2]>-200.f)break;
254       ret[i][m][0]=j;
255 
256       for(j=EHMER_MAX-1;j>EHMER_OFFSET+1;j--)
257         if(ret[i][m][j+2]>-200.f)
258           break;
259       ret[i][m][1]=j;
260 
261     }
262   }
263 
264   return(ret);
265 }
266 
_vp_psy_init(vorbis_look_psy * p,vorbis_info_psy * vi,vorbis_info_psy_global * gi,int n,long rate)267 void _vp_psy_init(vorbis_look_psy *p,vorbis_info_psy *vi,
268                   vorbis_info_psy_global *gi,int n,long rate){
269   long i,j,lo=-99,hi=1;
270   long maxoc;
271   memset(p,0,sizeof(*p));
272 
273   p->eighth_octave_lines=gi->eighth_octave_lines;
274   p->shiftoc=rint(log(gi->eighth_octave_lines*8.f)/log(2.f))-1;
275 
276   p->firstoc=toOC(.25f*rate*.5/n)*(1<<(p->shiftoc+1))-gi->eighth_octave_lines;
277   maxoc=toOC((n+.25f)*rate*.5/n)*(1<<(p->shiftoc+1))+.5f;
278   p->total_octave_lines=maxoc-p->firstoc+1;
279   p->ath=_ogg_malloc(n*sizeof(*p->ath));
280 
281   p->octave=_ogg_malloc(n*sizeof(*p->octave));
282   p->bark=_ogg_malloc(n*sizeof(*p->bark));
283   p->vi=vi;
284   p->n=n;
285   p->rate=rate;
286 
287   /* AoTuV HF weighting */
288   p->m_val = 1.;
289   if(rate < 26000) p->m_val = 0;
290   else if(rate < 38000) p->m_val = .94;   /* 32kHz */
291   else if(rate > 46000) p->m_val = 1.275; /* 48kHz */
292 
293   /* set up the lookups for a given blocksize and sample rate */
294 
295   for(i=0,j=0;i<MAX_ATH-1;i++){
296     int endpos=rint(fromOC((i+1)*.125-2.)*2*n/rate);
297     float base=ATH[i];
298     if(j<endpos){
299       float delta=(ATH[i+1]-base)/(endpos-j);
300       for(;j<endpos && j<n;j++){
301         p->ath[j]=base+100.;
302         base+=delta;
303       }
304     }
305   }
306 
307   for(;j<n;j++){
308     p->ath[j]=p->ath[j-1];
309   }
310 
311   for(i=0;i<n;i++){
312     float bark=toBARK(rate/(2*n)*i);
313 
314     for(;lo+vi->noisewindowlomin<i &&
315           toBARK(rate/(2*n)*lo)<(bark-vi->noisewindowlo);lo++);
316 
317     for(;hi<=n && (hi<i+vi->noisewindowhimin ||
318           toBARK(rate/(2*n)*hi)<(bark+vi->noisewindowhi));hi++);
319 
320     p->bark[i]=((lo-1)<<16)+(hi-1);
321 
322   }
323 
324   for(i=0;i<n;i++)
325     p->octave[i]=toOC((i+.25f)*.5*rate/n)*(1<<(p->shiftoc+1))+.5f;
326 
327   p->tonecurves=setup_tone_curves(vi->toneatt,rate*.5/n,n,
328                                   vi->tone_centerboost,vi->tone_decay);
329 
330   /* set up rolling noise median */
331   p->noiseoffset=_ogg_malloc(P_NOISECURVES*sizeof(*p->noiseoffset));
332   for(i=0;i<P_NOISECURVES;i++)
333     p->noiseoffset[i]=_ogg_malloc(n*sizeof(**p->noiseoffset));
334 
335   for(i=0;i<n;i++){
336     float halfoc=toOC((i+.5)*rate/(2.*n))*2.;
337     int inthalfoc;
338     float del;
339 
340     if(halfoc<0)halfoc=0;
341     if(halfoc>=P_BANDS-1)halfoc=P_BANDS-1;
342     inthalfoc=(int)halfoc;
343     del=halfoc-inthalfoc;
344 
345     for(j=0;j<P_NOISECURVES;j++)
346       p->noiseoffset[j][i]=
347         p->vi->noiseoff[j][inthalfoc]*(1.-del) +
348         p->vi->noiseoff[j][inthalfoc+1]*del;
349 
350   }
351 #if 0
352   {
353     static int ls=0;
354     _analysis_output_always("noiseoff0",ls,p->noiseoffset[0],n,1,0,0);
355     _analysis_output_always("noiseoff1",ls,p->noiseoffset[1],n,1,0,0);
356     _analysis_output_always("noiseoff2",ls++,p->noiseoffset[2],n,1,0,0);
357   }
358 #endif
359 }
360 
_vp_psy_clear(vorbis_look_psy * p)361 void _vp_psy_clear(vorbis_look_psy *p){
362   int i,j;
363   if(p){
364     if(p->ath)_ogg_free(p->ath);
365     if(p->octave)_ogg_free(p->octave);
366     if(p->bark)_ogg_free(p->bark);
367     if(p->tonecurves){
368       for(i=0;i<P_BANDS;i++){
369         for(j=0;j<P_LEVELS;j++){
370           _ogg_free(p->tonecurves[i][j]);
371         }
372         _ogg_free(p->tonecurves[i]);
373       }
374       _ogg_free(p->tonecurves);
375     }
376     if(p->noiseoffset){
377       for(i=0;i<P_NOISECURVES;i++){
378         _ogg_free(p->noiseoffset[i]);
379       }
380       _ogg_free(p->noiseoffset);
381     }
382     memset(p,0,sizeof(*p));
383   }
384 }
385 
386 /* octave/(8*eighth_octave_lines) x scale and dB y scale */
seed_curve(float * seed,const float ** curves,float amp,int oc,int n,int linesper,float dBoffset)387 static void seed_curve(float *seed,
388                        const float **curves,
389                        float amp,
390                        int oc, int n,
391                        int linesper,float dBoffset){
392   int i,post1;
393   int seedptr;
394   const float *posts,*curve;
395 
396   int choice=(int)((amp+dBoffset-P_LEVEL_0)*.1f);
397   choice=max(choice,0);
398   choice=min(choice,P_LEVELS-1);
399   posts=curves[choice];
400   curve=posts+2;
401   post1=(int)posts[1];
402   seedptr=oc+(posts[0]-EHMER_OFFSET)*linesper-(linesper>>1);
403 
404   for(i=posts[0];i<post1;i++){
405     if(seedptr>0){
406       float lin=amp+curve[i];
407       if(seed[seedptr]<lin)seed[seedptr]=lin;
408     }
409     seedptr+=linesper;
410     if(seedptr>=n)break;
411   }
412 }
413 
seed_loop(vorbis_look_psy * p,const float *** curves,const float * f,const float * flr,float * seed,float specmax)414 static void seed_loop(vorbis_look_psy *p,
415                       const float ***curves,
416                       const float *f,
417                       const float *flr,
418                       float *seed,
419                       float specmax){
420   vorbis_info_psy *vi=p->vi;
421   long n=p->n,i;
422   float dBoffset=vi->max_curve_dB-specmax;
423 
424   /* prime the working vector with peak values */
425 
426   for(i=0;i<n;i++){
427     float max=f[i];
428     long oc=p->octave[i];
429     while(i+1<n && p->octave[i+1]==oc){
430       i++;
431       if(f[i]>max)max=f[i];
432     }
433 
434     if(max+6.f>flr[i]){
435       oc=oc>>p->shiftoc;
436 
437       if(oc>=P_BANDS)oc=P_BANDS-1;
438       if(oc<0)oc=0;
439 
440       seed_curve(seed,
441                  curves[oc],
442                  max,
443                  p->octave[i]-p->firstoc,
444                  p->total_octave_lines,
445                  p->eighth_octave_lines,
446                  dBoffset);
447     }
448   }
449 }
450 
seed_chase(float * seeds,int linesper,long n)451 static void seed_chase(float *seeds, int linesper, long n){
452   long  *posstack=alloca(n*sizeof(*posstack));
453   float *ampstack=alloca(n*sizeof(*ampstack));
454   long   stack=0;
455   long   pos=0;
456   long   i;
457 
458   for(i=0;i<n;i++){
459     if(stack<2){
460       posstack[stack]=i;
461       ampstack[stack++]=seeds[i];
462     }else{
463       while(1){
464         if(seeds[i]<ampstack[stack-1]){
465           posstack[stack]=i;
466           ampstack[stack++]=seeds[i];
467           break;
468         }else{
469           if(i<posstack[stack-1]+linesper){
470             if(stack>1 && ampstack[stack-1]<=ampstack[stack-2] &&
471                i<posstack[stack-2]+linesper){
472               /* we completely overlap, making stack-1 irrelevant.  pop it */
473               stack--;
474               continue;
475             }
476           }
477           posstack[stack]=i;
478           ampstack[stack++]=seeds[i];
479           break;
480 
481         }
482       }
483     }
484   }
485 
486   /* the stack now contains only the positions that are relevant. Scan
487      'em straight through */
488 
489   for(i=0;i<stack;i++){
490     long endpos;
491     if(i<stack-1 && ampstack[i+1]>ampstack[i]){
492       endpos=posstack[i+1];
493     }else{
494       endpos=posstack[i]+linesper+1; /* +1 is important, else bin 0 is
495                                         discarded in short frames */
496     }
497     if(endpos>n)endpos=n;
498     for(;pos<endpos;pos++)
499       seeds[pos]=ampstack[i];
500   }
501 
502   /* there.  Linear time.  I now remember this was on a problem set I
503      had in Grad Skool... I didn't solve it at the time ;-) */
504 
505 }
506 
507 /* bleaugh, this is more complicated than it needs to be */
508 #include<stdio.h>
max_seeds(vorbis_look_psy * p,float * seed,float * flr)509 static void max_seeds(vorbis_look_psy *p,
510                       float *seed,
511                       float *flr){
512   long   n=p->total_octave_lines;
513   int    linesper=p->eighth_octave_lines;
514   long   linpos=0;
515   long   pos;
516 
517   seed_chase(seed,linesper,n); /* for masking */
518 
519   pos=p->octave[0]-p->firstoc-(linesper>>1);
520 
521   while(linpos+1<p->n){
522     float minV=seed[pos];
523     long end=((p->octave[linpos]+p->octave[linpos+1])>>1)-p->firstoc;
524     if(minV>p->vi->tone_abs_limit)minV=p->vi->tone_abs_limit;
525     while(pos+1<=end){
526       pos++;
527       if((seed[pos]>NEGINF && seed[pos]<minV) || minV==NEGINF)
528         minV=seed[pos];
529     }
530 
531     end=pos+p->firstoc;
532     for(;linpos<p->n && p->octave[linpos]<=end;linpos++)
533       if(flr[linpos]<minV)flr[linpos]=minV;
534   }
535 
536   {
537     float minV=seed[p->total_octave_lines-1];
538     for(;linpos<p->n;linpos++)
539       if(flr[linpos]<minV)flr[linpos]=minV;
540   }
541 
542 }
543 
bark_noise_hybridmp(int n,const long * b,const float * f,float * noise,const float offset,const int fixed)544 static void bark_noise_hybridmp(int n,const long *b,
545                                 const float *f,
546                                 float *noise,
547                                 const float offset,
548                                 const int fixed){
549 
550   float *N=alloca(n*sizeof(*N));
551   float *X=alloca(n*sizeof(*N));
552   float *XX=alloca(n*sizeof(*N));
553   float *Y=alloca(n*sizeof(*N));
554   float *XY=alloca(n*sizeof(*N));
555 
556   float tN, tX, tXX, tY, tXY;
557   int i;
558 
559   int lo, hi;
560   float R=0.f;
561   float A=0.f;
562   float B=0.f;
563   float D=1.f;
564   float w, x, y;
565 
566   tN = tX = tXX = tY = tXY = 0.f;
567 
568   y = f[0] + offset;
569   if (y < 1.f) y = 1.f;
570 
571   w = y * y * .5;
572 
573   tN += w;
574   tX += w;
575   tY += w * y;
576 
577   N[0] = tN;
578   X[0] = tX;
579   XX[0] = tXX;
580   Y[0] = tY;
581   XY[0] = tXY;
582 
583   for (i = 1, x = 1.f; i < n; i++, x += 1.f) {
584 
585     y = f[i] + offset;
586     if (y < 1.f) y = 1.f;
587 
588     w = y * y;
589 
590     tN += w;
591     tX += w * x;
592     tXX += w * x * x;
593     tY += w * y;
594     tXY += w * x * y;
595 
596     N[i] = tN;
597     X[i] = tX;
598     XX[i] = tXX;
599     Y[i] = tY;
600     XY[i] = tXY;
601   }
602 
603   for (i = 0, x = 0.f;; i++, x += 1.f) {
604 
605     lo = b[i] >> 16;
606     if( lo>=0 ) break;
607     hi = b[i] & 0xffff;
608 
609     tN = N[hi] + N[-lo];
610     tX = X[hi] - X[-lo];
611     tXX = XX[hi] + XX[-lo];
612     tY = Y[hi] + Y[-lo];
613     tXY = XY[hi] - XY[-lo];
614 
615     A = tY * tXX - tX * tXY;
616     B = tN * tXY - tX * tY;
617     D = tN * tXX - tX * tX;
618     R = (A + x * B) / D;
619     if (R < 0.f)
620       R = 0.f;
621 
622     noise[i] = R - offset;
623   }
624 
625   for ( ;; i++, x += 1.f) {
626 
627     lo = b[i] >> 16;
628     hi = b[i] & 0xffff;
629     if(hi>=n)break;
630 
631     tN = N[hi] - N[lo];
632     tX = X[hi] - X[lo];
633     tXX = XX[hi] - XX[lo];
634     tY = Y[hi] - Y[lo];
635     tXY = XY[hi] - XY[lo];
636 
637     A = tY * tXX - tX * tXY;
638     B = tN * tXY - tX * tY;
639     D = tN * tXX - tX * tX;
640     R = (A + x * B) / D;
641     if (R < 0.f) R = 0.f;
642 
643     noise[i] = R - offset;
644   }
645   for ( ; i < n; i++, x += 1.f) {
646 
647     R = (A + x * B) / D;
648     if (R < 0.f) R = 0.f;
649 
650     noise[i] = R - offset;
651   }
652 
653   if (fixed <= 0) return;
654 
655   for (i = 0, x = 0.f;; i++, x += 1.f) {
656     hi = i + fixed / 2;
657     lo = hi - fixed;
658     if(lo>=0)break;
659 
660     tN = N[hi] + N[-lo];
661     tX = X[hi] - X[-lo];
662     tXX = XX[hi] + XX[-lo];
663     tY = Y[hi] + Y[-lo];
664     tXY = XY[hi] - XY[-lo];
665 
666 
667     A = tY * tXX - tX * tXY;
668     B = tN * tXY - tX * tY;
669     D = tN * tXX - tX * tX;
670     R = (A + x * B) / D;
671 
672     if (R - offset < noise[i]) noise[i] = R - offset;
673   }
674   for ( ;; i++, x += 1.f) {
675 
676     hi = i + fixed / 2;
677     lo = hi - fixed;
678     if(hi>=n)break;
679 
680     tN = N[hi] - N[lo];
681     tX = X[hi] - X[lo];
682     tXX = XX[hi] - XX[lo];
683     tY = Y[hi] - Y[lo];
684     tXY = XY[hi] - XY[lo];
685 
686     A = tY * tXX - tX * tXY;
687     B = tN * tXY - tX * tY;
688     D = tN * tXX - tX * tX;
689     R = (A + x * B) / D;
690 
691     if (R - offset < noise[i]) noise[i] = R - offset;
692   }
693   for ( ; i < n; i++, x += 1.f) {
694     R = (A + x * B) / D;
695     if (R - offset < noise[i]) noise[i] = R - offset;
696   }
697 }
698 
_vp_noisemask(vorbis_look_psy * p,float * logmdct,float * logmask)699 void _vp_noisemask(vorbis_look_psy *p,
700                    float *logmdct,
701                    float *logmask){
702 
703   int i,n=p->n;
704   float *work=alloca(n*sizeof(*work));
705 
706   bark_noise_hybridmp(n,p->bark,logmdct,logmask,
707                       140.,-1);
708 
709   for(i=0;i<n;i++)work[i]=logmdct[i]-logmask[i];
710 
711   bark_noise_hybridmp(n,p->bark,work,logmask,0.,
712                       p->vi->noisewindowfixed);
713 
714   for(i=0;i<n;i++)work[i]=logmdct[i]-work[i];
715 
716 #if 0
717   {
718     static int seq=0;
719 
720     float work2[n];
721     for(i=0;i<n;i++){
722       work2[i]=logmask[i]+work[i];
723     }
724 
725     if(seq&1)
726       _analysis_output("median2R",seq/2,work,n,1,0,0);
727     else
728       _analysis_output("median2L",seq/2,work,n,1,0,0);
729 
730     if(seq&1)
731       _analysis_output("envelope2R",seq/2,work2,n,1,0,0);
732     else
733       _analysis_output("envelope2L",seq/2,work2,n,1,0,0);
734     seq++;
735   }
736 #endif
737 
738   for(i=0;i<n;i++){
739     int dB=logmask[i]+.5;
740     if(dB>=NOISE_COMPAND_LEVELS)dB=NOISE_COMPAND_LEVELS-1;
741     if(dB<0)dB=0;
742     logmask[i]= work[i]+p->vi->noisecompand[dB];
743   }
744 
745 }
746 
_vp_tonemask(vorbis_look_psy * p,float * logfft,float * logmask,float global_specmax,float local_specmax)747 void _vp_tonemask(vorbis_look_psy *p,
748                   float *logfft,
749                   float *logmask,
750                   float global_specmax,
751                   float local_specmax){
752 
753   int i,n=p->n;
754 
755   float *seed=alloca(sizeof(*seed)*p->total_octave_lines);
756   float att=local_specmax+p->vi->ath_adjatt;
757   for(i=0;i<p->total_octave_lines;i++)seed[i]=NEGINF;
758 
759   /* set the ATH (floating below localmax, not global max by a
760      specified att) */
761   if(att<p->vi->ath_maxatt)att=p->vi->ath_maxatt;
762 
763   for(i=0;i<n;i++)
764     logmask[i]=p->ath[i]+att;
765 
766   /* tone masking */
767   seed_loop(p,(const float ***)p->tonecurves,logfft,logmask,seed,global_specmax);
768   max_seeds(p,seed,logmask);
769 
770 }
771 
_vp_offset_and_mix(vorbis_look_psy * p,float * noise,float * tone,int offset_select,float * logmask,float * mdct,float * logmdct)772 void _vp_offset_and_mix(vorbis_look_psy *p,
773                         float *noise,
774                         float *tone,
775                         int offset_select,
776                         float *logmask,
777                         float *mdct,
778                         float *logmdct){
779   int i,n=p->n;
780   float de, coeffi, cx;/* AoTuV */
781   float toneatt=p->vi->tone_masteratt[offset_select];
782 
783   cx = p->m_val;
784 
785   for(i=0;i<n;i++){
786     float val= noise[i]+p->noiseoffset[offset_select][i];
787     if(val>p->vi->noisemaxsupp)val=p->vi->noisemaxsupp;
788     logmask[i]=max(val,tone[i]+toneatt);
789 
790 
791     /* AoTuV */
792     /** @ M1 **
793         The following codes improve a noise problem.
794         A fundamental idea uses the value of masking and carries out
795         the relative compensation of the MDCT.
796         However, this code is not perfect and all noise problems cannot be solved.
797         by Aoyumi @ 2004/04/18
798     */
799 
800     if(offset_select == 1) {
801       coeffi = -17.2;       /* coeffi is a -17.2dB threshold */
802       val = val - logmdct[i];  /* val == mdct line value relative to floor in dB */
803 
804       if(val > coeffi){
805         /* mdct value is > -17.2 dB below floor */
806 
807         de = 1.0-((val-coeffi)*0.005*cx);
808         /* pro-rated attenuation:
809            -0.00 dB boost if mdct value is -17.2dB (relative to floor)
810            -0.77 dB boost if mdct value is 0dB (relative to floor)
811            -1.64 dB boost if mdct value is +17.2dB (relative to floor)
812            etc... */
813 
814         if(de < 0) de = 0.0001;
815       }else
816         /* mdct value is <= -17.2 dB below floor */
817 
818         de = 1.0-((val-coeffi)*0.0003*cx);
819       /* pro-rated attenuation:
820          +0.00 dB atten if mdct value is -17.2dB (relative to floor)
821          +0.45 dB atten if mdct value is -34.4dB (relative to floor)
822          etc... */
823 
824       mdct[i] *= de;
825 
826     }
827   }
828 }
829 
_vp_ampmax_decay(float amp,vorbis_dsp_state * vd)830 float _vp_ampmax_decay(float amp,vorbis_dsp_state *vd){
831   vorbis_info *vi=vd->vi;
832   codec_setup_info *ci=vi->codec_setup;
833   vorbis_info_psy_global *gi=&ci->psy_g_param;
834 
835   int n=ci->blocksizes[vd->W]/2;
836   float secs=(float)n/vi->rate;
837 
838   amp+=secs*gi->ampmax_att_per_sec;
839   if(amp<-9999)amp=-9999;
840   return(amp);
841 }
842 
843 static float FLOOR1_fromdB_LOOKUP[256]={
844   1.0649863e-07F, 1.1341951e-07F, 1.2079015e-07F, 1.2863978e-07F,
845   1.3699951e-07F, 1.4590251e-07F, 1.5538408e-07F, 1.6548181e-07F,
846   1.7623575e-07F, 1.8768855e-07F, 1.9988561e-07F, 2.128753e-07F,
847   2.2670913e-07F, 2.4144197e-07F, 2.5713223e-07F, 2.7384213e-07F,
848   2.9163793e-07F, 3.1059021e-07F, 3.3077411e-07F, 3.5226968e-07F,
849   3.7516214e-07F, 3.9954229e-07F, 4.2550680e-07F, 4.5315863e-07F,
850   4.8260743e-07F, 5.1396998e-07F, 5.4737065e-07F, 5.8294187e-07F,
851   6.2082472e-07F, 6.6116941e-07F, 7.0413592e-07F, 7.4989464e-07F,
852   7.9862701e-07F, 8.5052630e-07F, 9.0579828e-07F, 9.6466216e-07F,
853   1.0273513e-06F, 1.0941144e-06F, 1.1652161e-06F, 1.2409384e-06F,
854   1.3215816e-06F, 1.4074654e-06F, 1.4989305e-06F, 1.5963394e-06F,
855   1.7000785e-06F, 1.8105592e-06F, 1.9282195e-06F, 2.0535261e-06F,
856   2.1869758e-06F, 2.3290978e-06F, 2.4804557e-06F, 2.6416497e-06F,
857   2.8133190e-06F, 2.9961443e-06F, 3.1908506e-06F, 3.3982101e-06F,
858   3.6190449e-06F, 3.8542308e-06F, 4.1047004e-06F, 4.3714470e-06F,
859   4.6555282e-06F, 4.9580707e-06F, 5.2802740e-06F, 5.6234160e-06F,
860   5.9888572e-06F, 6.3780469e-06F, 6.7925283e-06F, 7.2339451e-06F,
861   7.7040476e-06F, 8.2047000e-06F, 8.7378876e-06F, 9.3057248e-06F,
862   9.9104632e-06F, 1.0554501e-05F, 1.1240392e-05F, 1.1970856e-05F,
863   1.2748789e-05F, 1.3577278e-05F, 1.4459606e-05F, 1.5399272e-05F,
864   1.6400004e-05F, 1.7465768e-05F, 1.8600792e-05F, 1.9809576e-05F,
865   2.1096914e-05F, 2.2467911e-05F, 2.3928002e-05F, 2.5482978e-05F,
866   2.7139006e-05F, 2.8902651e-05F, 3.0780908e-05F, 3.2781225e-05F,
867   3.4911534e-05F, 3.7180282e-05F, 3.9596466e-05F, 4.2169667e-05F,
868   4.4910090e-05F, 4.7828601e-05F, 5.0936773e-05F, 5.4246931e-05F,
869   5.7772202e-05F, 6.1526565e-05F, 6.5524908e-05F, 6.9783085e-05F,
870   7.4317983e-05F, 7.9147585e-05F, 8.4291040e-05F, 8.9768747e-05F,
871   9.5602426e-05F, 0.00010181521F, 0.00010843174F, 0.00011547824F,
872   0.00012298267F, 0.00013097477F, 0.00013948625F, 0.00014855085F,
873   0.00015820453F, 0.00016848555F, 0.00017943469F, 0.00019109536F,
874   0.00020351382F, 0.00021673929F, 0.00023082423F, 0.00024582449F,
875   0.00026179955F, 0.00027881276F, 0.00029693158F, 0.00031622787F,
876   0.00033677814F, 0.00035866388F, 0.00038197188F, 0.00040679456F,
877   0.00043323036F, 0.00046138411F, 0.00049136745F, 0.00052329927F,
878   0.00055730621F, 0.00059352311F, 0.00063209358F, 0.00067317058F,
879   0.00071691700F, 0.00076350630F, 0.00081312324F, 0.00086596457F,
880   0.00092223983F, 0.00098217216F, 0.0010459992F, 0.0011139742F,
881   0.0011863665F, 0.0012634633F, 0.0013455702F, 0.0014330129F,
882   0.0015261382F, 0.0016253153F, 0.0017309374F, 0.0018434235F,
883   0.0019632195F, 0.0020908006F, 0.0022266726F, 0.0023713743F,
884   0.0025254795F, 0.0026895994F, 0.0028643847F, 0.0030505286F,
885   0.0032487691F, 0.0034598925F, 0.0036847358F, 0.0039241906F,
886   0.0041792066F, 0.0044507950F, 0.0047400328F, 0.0050480668F,
887   0.0053761186F, 0.0057254891F, 0.0060975636F, 0.0064938176F,
888   0.0069158225F, 0.0073652516F, 0.0078438871F, 0.0083536271F,
889   0.0088964928F, 0.009474637F, 0.010090352F, 0.010746080F,
890   0.011444421F, 0.012188144F, 0.012980198F, 0.013823725F,
891   0.014722068F, 0.015678791F, 0.016697687F, 0.017782797F,
892   0.018938423F, 0.020169149F, 0.021479854F, 0.022875735F,
893   0.024362330F, 0.025945531F, 0.027631618F, 0.029427276F,
894   0.031339626F, 0.033376252F, 0.035545228F, 0.037855157F,
895   0.040315199F, 0.042935108F, 0.045725273F, 0.048696758F,
896   0.051861348F, 0.055231591F, 0.058820850F, 0.062643361F,
897   0.066714279F, 0.071049749F, 0.075666962F, 0.080584227F,
898   0.085821044F, 0.091398179F, 0.097337747F, 0.10366330F,
899   0.11039993F, 0.11757434F, 0.12521498F, 0.13335215F,
900   0.14201813F, 0.15124727F, 0.16107617F, 0.17154380F,
901   0.18269168F, 0.19456402F, 0.20720788F, 0.22067342F,
902   0.23501402F, 0.25028656F, 0.26655159F, 0.28387361F,
903   0.30232132F, 0.32196786F, 0.34289114F, 0.36517414F,
904   0.38890521F, 0.41417847F, 0.44109412F, 0.46975890F,
905   0.50028648F, 0.53279791F, 0.56742212F, 0.60429640F,
906   0.64356699F, 0.68538959F, 0.72993007F, 0.77736504F,
907   0.82788260F, 0.88168307F, 0.9389798F, 1.F,
908 };
909 
910 /* this is for per-channel noise normalization */
apsort(const void * a,const void * b)911 static int apsort(const void *a, const void *b){
912   float f1=**(float**)a;
913   float f2=**(float**)b;
914   return (f1<f2)-(f1>f2);
915 }
916 
flag_lossless(int limit,float prepoint,float postpoint,float * mdct,float * floor,int * flag,int i,int jn)917 static void flag_lossless(int limit, float prepoint, float postpoint, float *mdct,
918                          float *floor, int *flag, int i, int jn){
919   int j;
920   for(j=0;j<jn;j++){
921     float point = j>=limit-i ? postpoint : prepoint;
922     float r = fabs(mdct[j])/floor[j];
923     if(r<point)
924       flag[j]=0;
925     else
926       flag[j]=1;
927   }
928 }
929 
930 /* Overload/Side effect: On input, the *q vector holds either the
931    quantized energy (for elements with the flag set) or the absolute
932    values of the *r vector (for elements with flag unset).  On output,
933    *q holds the quantized energy for all elements */
noise_normalize(vorbis_look_psy * p,int limit,float * r,float * q,float * f,int * flags,float acc,int i,int n,int * out)934 static float noise_normalize(vorbis_look_psy *p, int limit, float *r, float *q, float *f, int *flags, float acc, int i, int n, int *out){
935 
936   vorbis_info_psy *vi=p->vi;
937   float **sort = alloca(n*sizeof(*sort));
938   int j,count=0;
939   int start = (vi->normal_p ? vi->normal_start-i : n);
940   if(start>n)start=n;
941 
942   /* force classic behavior where only energy in the current band is considered */
943   acc=0.f;
944 
945   /* still responsible for populating *out where noise norm not in
946      effect.  There's no need to [re]populate *q in these areas */
947   for(j=0;j<start;j++){
948     if(!flags || !flags[j]){ /* lossless coupling already quantized.
949                                 Don't touch; requantizing based on
950                                 energy would be incorrect. */
951       float ve = q[j]/f[j];
952       if(r[j]<0)
953         out[j] = -rint(sqrt(ve));
954       else
955         out[j] = rint(sqrt(ve));
956     }
957   }
958 
959   /* sort magnitudes for noise norm portion of partition */
960   for(;j<n;j++){
961     if(!flags || !flags[j]){ /* can't noise norm elements that have
962                                 already been loslessly coupled; we can
963                                 only account for their energy error */
964       float ve = q[j]/f[j];
965       /* Despite all the new, more capable coupling code, for now we
966          implement noise norm as it has been up to this point. Only
967          consider promotions to unit magnitude from 0.  In addition
968          the only energy error counted is quantizations to zero. */
969       /* also-- the original point code only applied noise norm at > pointlimit */
970       if(ve<.25f && (!flags || j>=limit-i)){
971         acc += ve;
972         sort[count++]=q+j; /* q is fabs(r) for unflagged element */
973       }else{
974         /* For now: no acc adjustment for nonzero quantization.  populate *out and q as this value is final. */
975         if(r[j]<0)
976           out[j] = -rint(sqrt(ve));
977         else
978           out[j] = rint(sqrt(ve));
979         q[j] = out[j]*out[j]*f[j];
980       }
981     }/* else{
982         again, no energy adjustment for error in nonzero quant-- for now
983         }*/
984   }
985 
986   if(count){
987     /* noise norm to do */
988     qsort(sort,count,sizeof(*sort),apsort);
989     for(j=0;j<count;j++){
990       int k=sort[j]-q;
991       if(acc>=vi->normal_thresh){
992         out[k]=unitnorm(r[k]);
993         acc-=1.f;
994         q[k]=f[k];
995       }else{
996         out[k]=0;
997         q[k]=0.f;
998       }
999     }
1000   }
1001 
1002   return acc;
1003 }
1004 
1005 /* Noise normalization, quantization and coupling are not wholly
1006    seperable processes in depth>1 coupling. */
_vp_couple_quantize_normalize(int blobno,vorbis_info_psy_global * g,vorbis_look_psy * p,vorbis_info_mapping0 * vi,float ** mdct,int ** iwork,int * nonzero,int sliding_lowpass,int ch)1007 void _vp_couple_quantize_normalize(int blobno,
1008                                    vorbis_info_psy_global *g,
1009                                    vorbis_look_psy *p,
1010                                    vorbis_info_mapping0 *vi,
1011                                    float **mdct,
1012                                    int   **iwork,
1013                                    int    *nonzero,
1014                                    int     sliding_lowpass,
1015                                    int     ch){
1016 
1017   int i;
1018   int n = p->n;
1019   int partition=(p->vi->normal_p ? p->vi->normal_partition : 16);
1020   int limit = g->coupling_pointlimit[p->vi->blockflag][blobno];
1021   float prepoint=stereo_threshholds[g->coupling_prepointamp[blobno]];
1022   float postpoint=stereo_threshholds[g->coupling_postpointamp[blobno]];
1023   float de=0.1*p->m_val; /* a blend of the AoTuV M2 and M3 code here and below */
1024 
1025   /* mdct is our raw mdct output, floor not removed. */
1026   /* inout passes in the ifloor, passes back quantized result */
1027 
1028   /* unquantized energy (negative indicates amplitude has negative sign) */
1029   float **raw = alloca(ch*sizeof(*raw));
1030 
1031   /* dual pupose; quantized energy (if flag set), othersize fabs(raw) */
1032   float **quant = alloca(ch*sizeof(*quant));
1033 
1034   /* floor energy */
1035   float **floor = alloca(ch*sizeof(*floor));
1036 
1037   /* flags indicating raw/quantized status of elements in raw vector */
1038   int   **flag  = alloca(ch*sizeof(*flag));
1039 
1040   /* non-zero flag working vector */
1041   int    *nz    = alloca(ch*sizeof(*nz));
1042 
1043   /* energy surplus/defecit tracking */
1044   float  *acc   = alloca((ch+vi->coupling_steps)*sizeof(*acc));
1045 
1046   /* The threshold of a stereo is changed with the size of n */
1047   if(n > 1000)
1048     postpoint=stereo_threshholds_limited[g->coupling_postpointamp[blobno]];
1049 
1050   raw[0]   = alloca(ch*partition*sizeof(**raw));
1051   quant[0] = alloca(ch*partition*sizeof(**quant));
1052   floor[0] = alloca(ch*partition*sizeof(**floor));
1053   flag[0]  = alloca(ch*partition*sizeof(**flag));
1054 
1055   for(i=1;i<ch;i++){
1056     raw[i]   = &raw[0][partition*i];
1057     quant[i] = &quant[0][partition*i];
1058     floor[i] = &floor[0][partition*i];
1059     flag[i]  = &flag[0][partition*i];
1060   }
1061   for(i=0;i<ch+vi->coupling_steps;i++)
1062     acc[i]=0.f;
1063 
1064   for(i=0;i<n;i+=partition){
1065     int k,j,jn = partition > n-i ? n-i : partition;
1066     int step,track = 0;
1067 
1068     memcpy(nz,nonzero,sizeof(*nz)*ch);
1069 
1070     /* prefill */
1071     memset(flag[0],0,ch*partition*sizeof(**flag));
1072     for(k=0;k<ch;k++){
1073       int *iout = &iwork[k][i];
1074       if(nz[k]){
1075 
1076         for(j=0;j<jn;j++)
1077           floor[k][j] = FLOOR1_fromdB_LOOKUP[iout[j]];
1078 
1079         flag_lossless(limit,prepoint,postpoint,&mdct[k][i],floor[k],flag[k],i,jn);
1080 
1081         for(j=0;j<jn;j++){
1082           quant[k][j] = raw[k][j] = mdct[k][i+j]*mdct[k][i+j];
1083           if(mdct[k][i+j]<0.f) raw[k][j]*=-1.f;
1084           floor[k][j]*=floor[k][j];
1085         }
1086 
1087         acc[track]=noise_normalize(p,limit,raw[k],quant[k],floor[k],NULL,acc[track],i,jn,iout);
1088 
1089       }else{
1090         for(j=0;j<jn;j++){
1091           floor[k][j] = 1e-10f;
1092           raw[k][j] = 0.f;
1093           quant[k][j] = 0.f;
1094           flag[k][j] = 0;
1095           iout[j]=0;
1096         }
1097         acc[track]=0.f;
1098       }
1099       track++;
1100     }
1101 
1102     /* coupling */
1103     for(step=0;step<vi->coupling_steps;step++){
1104       int Mi = vi->coupling_mag[step];
1105       int Ai = vi->coupling_ang[step];
1106       int *iM = &iwork[Mi][i];
1107       int *iA = &iwork[Ai][i];
1108       float *reM = raw[Mi];
1109       float *reA = raw[Ai];
1110       float *qeM = quant[Mi];
1111       float *qeA = quant[Ai];
1112       float *floorM = floor[Mi];
1113       float *floorA = floor[Ai];
1114       int *fM = flag[Mi];
1115       int *fA = flag[Ai];
1116 
1117       if(nz[Mi] || nz[Ai]){
1118         nz[Mi] = nz[Ai] = 1;
1119 
1120         for(j=0;j<jn;j++){
1121 
1122           if(j<sliding_lowpass-i){
1123             if(fM[j] || fA[j]){
1124               /* lossless coupling */
1125 
1126               reM[j] = fabs(reM[j])+fabs(reA[j]);
1127               qeM[j] = qeM[j]+qeA[j];
1128               fM[j]=fA[j]=1;
1129 
1130               /* couple iM/iA */
1131               {
1132                 int A = iM[j];
1133                 int B = iA[j];
1134 
1135                 if(abs(A)>abs(B)){
1136                   iA[j]=(A>0?A-B:B-A);
1137                 }else{
1138                   iA[j]=(B>0?A-B:B-A);
1139                   iM[j]=B;
1140                 }
1141 
1142                 /* collapse two equivalent tuples to one */
1143                 if(iA[j]>=abs(iM[j])*2){
1144                   iA[j]= -iA[j];
1145                   iM[j]= -iM[j];
1146                 }
1147 
1148               }
1149 
1150             }else{
1151               /* lossy (point) coupling */
1152               if(j<limit-i){
1153                 /* dipole */
1154                 reM[j] += reA[j];
1155                 qeM[j] = fabs(reM[j]);
1156               }else{
1157                 /* AoTuV */
1158                 /** @ M2 **
1159                     The boost problem by the combination of noise normalization and point stereo is eased.
1160                     However, this is a temporary patch.
1161                     by Aoyumi @ 2004/04/18
1162                 */
1163                 float derate = (1.0 - de*((float)(j-limit+i) / (float)(n-limit)));
1164 
1165                 /* elliptical */
1166                 if(reM[j]+reA[j]<0){
1167                   reM[j] = - (qeM[j] = (fabs(reM[j])+fabs(reA[j]))*derate*derate);
1168                 }else{
1169                   reM[j] =   (qeM[j] = (fabs(reM[j])+fabs(reA[j]))*derate*derate);
1170                 }
1171               }
1172               reA[j]=qeA[j]=0.f;
1173               fA[j]=1;
1174               iA[j]=0;
1175             }
1176           }
1177           floorM[j]=floorA[j]=floorM[j]+floorA[j];
1178         }
1179         /* normalize the resulting mag vector */
1180         acc[track]=noise_normalize(p,limit,raw[Mi],quant[Mi],floor[Mi],flag[Mi],acc[track],i,jn,iM);
1181         track++;
1182       }
1183     }
1184   }
1185 
1186   for(i=0;i<vi->coupling_steps;i++){
1187     /* make sure coupling a zero and a nonzero channel results in two
1188        nonzero channels. */
1189     if(nonzero[vi->coupling_mag[i]] ||
1190        nonzero[vi->coupling_ang[i]]){
1191       nonzero[vi->coupling_mag[i]]=1;
1192       nonzero[vi->coupling_ang[i]]=1;
1193     }
1194   }
1195 }
1196