src/lib/dl/ext/vorbis/res0.c

   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: residue backend 0, 1 and 2 implementation
  14  last mod: $Id: res0.c 17556 2010-10-21 18:25:19Z tterribe $
  15
  16  ********************************************************************/
  17
  18 /* Slow, slow, slow, simpleminded and did I mention it was slow?  The
  19    encode/decode loops are coded for clarity and performance is not
  20    yet even a nagging little idea lurking in the shadows.  Oh and BTW,
  21    it's slow. */
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <math.h>
  26 #include <ext/libogg/ogg.h>
  27 #include "codec.h"
  28 #include "codec_internal.h"
  29 #include "registry.h"
  30 #include "codebook.h"
  31 #include "misc.h"
  32 #include "os.h"
  33
  34 //#define TRAIN_RES 1
  35 //#define TRAIN_RESAUX 1
  36
  37 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
  38 #include <stdio.h>
  39 #endif
  40
  41 typedef struct {
  42   vorbis_info_residue0 *info;
  43
  44   int         parts;
  45   int         stages;
  46   codebook   *fullbooks;
  47   codebook   *phrasebook;
  48   codebook ***partbooks;
  49
  50   int         partvals;
  51   int       **decodemap;
  52
  53   long      postbits;
  54   long      phrasebits;
  55   long      frames;
  56
  57 #if defined(TRAIN_RES) || defined(TRAIN_RESAUX)
  58   int        train_seq;
  59   long      *training_data[8][64];
  60   float      training_max[8][64];
  61   float      training_min[8][64];
  62   float     tmin;
  63   float     tmax;
  64   int       submap;
  65 #endif
  66
  67 } vorbis_look_residue0;
  68
  69 void res0_free_info(vorbis_info_residue *i){
  70   vorbis_info_residue0 *info=(vorbis_info_residue0 *)i;
  71   if(info){
  72     memset(info,0,sizeof(*info));
  73     _ogg_free(info);
  74   }
  75 }
  76
  77 void res0_free_look(vorbis_look_residue *i){
  78   int j;
  79   if(i){
  80
  81     vorbis_look_residue0 *look=(vorbis_look_residue0 *)i;
  82
  83 #ifdef TRAIN_RES
  84     {
  85       int j,k,l;
  86       for(j=0;j<look->parts;j++){
  87         /*fprintf(stderr,"partition %d: ",j);*/
  88         for(k=0;k<8;k++)
  89           if(look->training_data[k][j]){
  90             char buffer[80];
  91             FILE *of;
  92             codebook *statebook=look->partbooks[j][k];
  93
  94             /* long and short into the same bucket by current convention */
  95             sprintf(buffer,"res_sub%d_part%d_pass%d.vqd",look->submap,j,k);
  96             of=fopen(buffer,"a");
  97
  98             for(l=0;l<statebook->entries;l++)
  99               fprintf(of,"%d:%ld\n",l,look->training_data[k][j][l]);
 100
 101             fclose(of);
 102
 103             /*fprintf(stderr,"%d(%.2f|%.2f) ",k,
 104               look->training_min[k][j],look->training_max[k][j]);*/
 105
 106             _ogg_free(look->training_data[k][j]);
 107             look->training_data[k][j]=NULL;
 108           }
 109         /*fprintf(stderr,"\n");*/
 110       }
 111     }
 112     fprintf(stderr,"min/max residue: %g::%g\n",look->tmin,look->tmax);
 113
 114     /*fprintf(stderr,"residue bit usage %f:%f (%f total)\n",
 115             (float)look->phrasebits/look->frames,
 116             (float)look->postbits/look->frames,
 117             (float)(look->postbits+look->phrasebits)/look->frames);*/
 118 #endif
 119
 120
 121     /*vorbis_info_residue0 *info=look->info;
 122
 123     fprintf(stderr,
 124             "%ld frames encoded in %ld phrasebits and %ld residue bits "
 125             "(%g/frame) \n",look->frames,look->phrasebits,
 126             look->resbitsflat,
 127             (look->phrasebits+look->resbitsflat)/(float)look->frames);
 128
 129     for(j=0;j<look->parts;j++){
 130       long acc=0;
 131       fprintf(stderr,"\t[%d] == ",j);
 132       for(k=0;k<look->stages;k++)
 133         if((info->secondstages[j]>>k)&1){
 134           fprintf(stderr,"%ld,",look->resbits[j][k]);
 135           acc+=look->resbits[j][k];
 136         }
 137
 138       fprintf(stderr,":: (%ld vals) %1.2fbits/sample\n",look->resvals[j],
 139               acc?(float)acc/(look->resvals[j]*info->grouping):0);
 140     }
 141     fprintf(stderr,"\n");*/
 142
 143     for(j=0;j<look->parts;j++)
 144       if(look->partbooks[j])_ogg_free(look->partbooks[j]);
 145     _ogg_free(look->partbooks);
 146     for(j=0;j<look->partvals;j++)
 147       _ogg_free(look->decodemap[j]);
 148     _ogg_free(look->decodemap);
 149
 150     memset(look,0,sizeof(*look));
 151     _ogg_free(look);
 152   }
 153 }
 154
 155 static int ilog(unsigned int v){
 156   int ret=0;
 157   while(v){
 158     ret++;
 159     v>>=1;
 160   }
 161   return(ret);
 162 }
 163
 164 static int icount(unsigned int v){
 165   int ret=0;
 166   while(v){
 167     ret+=v&1;
 168     v>>=1;
 169   }
 170   return(ret);
 171 }
 172
 173
 174 void res0_pack(vorbis_info_residue *vr,oggpack_buffer *opb){
 175   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
 176   int j,acc=0;
 177   oggpack_write(opb,info->begin,24);
 178   oggpack_write(opb,info->end,24);
 179
 180   oggpack_write(opb,info->grouping-1,24);  /* residue vectors to group and
 181                                              code with a partitioned book */
 182   oggpack_write(opb,info->partitions-1,6); /* possible partition choices */
 183   oggpack_write(opb,info->groupbook,8);  /* group huffman book */
 184
 185   /* secondstages is a bitmask; as encoding progresses pass by pass, a
 186      bitmask of one indicates this partition class has bits to write
 187      this pass */
 188   for(j=0;j<info->partitions;j++){
 189     if(ilog(info->secondstages[j])>3){
 190       /* yes, this is a minor hack due to not thinking ahead */
 191       oggpack_write(opb,info->secondstages[j],3);
 192       oggpack_write(opb,1,1);
 193       oggpack_write(opb,info->secondstages[j]>>3,5);
 194     }else
 195       oggpack_write(opb,info->secondstages[j],4); /* trailing zero */
 196     acc+=icount(info->secondstages[j]);
 197   }
 198   for(j=0;j<acc;j++)
 199     oggpack_write(opb,info->booklist[j],8);
 200
 201 }
 202
 203 /* vorbis_info is for range checking */
 204 vorbis_info_residue *res0_unpack(vorbis_info *vi,oggpack_buffer *opb){
 205   int j,acc=0;
 206   vorbis_info_residue0 *info=_ogg_calloc(1,sizeof(*info));
 207   codec_setup_info     *ci=vi->codec_setup;
 208
 209   info->begin=oggpack_read(opb,24);
 210   info->end=oggpack_read(opb,24);
 211   info->grouping=oggpack_read(opb,24)+1;
 212   info->partitions=oggpack_read(opb,6)+1;
 213   info->groupbook=oggpack_read(opb,8);
 214
 215   /* check for premature EOP */
 216   if(info->groupbook<0)goto errout;
 217
 218   for(j=0;j<info->partitions;j++){
 219     int cascade=oggpack_read(opb,3);
 220     int cflag=oggpack_read(opb,1);
 221     if(cflag<0) goto errout;
 222     if(cflag){
 223       int c=oggpack_read(opb,5);
 224       if(c<0) goto errout;
 225       cascade|=(c<<3);
 226     }
 227     info->secondstages[j]=cascade;
 228
 229     acc+=icount(cascade);
 230   }
 231   for(j=0;j<acc;j++){
 232     int book=oggpack_read(opb,8);
 233     if(book<0) goto errout;
 234     info->booklist[j]=book;
 235   }
 236
 237   if(info->groupbook>=ci->books)goto errout;
 238   for(j=0;j<acc;j++){
 239     if(info->booklist[j]>=ci->books)goto errout;
 240     if(ci->book_param[info->booklist[j]]->maptype==0)goto errout;
 241   }
 242
 243   /* verify the phrasebook is not specifying an impossible or
 244      inconsistent partitioning scheme. */
 245   /* modify the phrasebook ranging check from r16327; an early beta
 246      encoder had a bug where it used an oversized phrasebook by
 247      accident.  These files should continue to be playable, but don't
 248      allow an exploit */
 249   {
 250     int entries = ci->book_param[info->groupbook]->entries;
 251     int dim = ci->book_param[info->groupbook]->dim;
 252     int partvals = 1;
 253     if (dim<1) goto errout;
 254     while(dim>0){
 255       partvals *= info->partitions;
 256       if(partvals > entries) goto errout;
 257       dim--;
 258     }
 259     info->partvals = partvals;
 260   }
 261
 262   return(info);
 263  errout:
 264   res0_free_info(info);
 265   return(NULL);
 266 }
 267
 268 vorbis_look_residue *res0_look(vorbis_dsp_state *vd,
 269                                vorbis_info_residue *vr){
 270   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
 271   vorbis_look_residue0 *look=_ogg_calloc(1,sizeof(*look));
 272   codec_setup_info     *ci=vd->vi->codec_setup;
 273
 274   int j,k,acc=0;
 275   int dim;
 276   int maxstage=0;
 277   look->info=info;
 278
 279   look->parts=info->partitions;
 280   look->fullbooks=ci->fullbooks;
 281   look->phrasebook=ci->fullbooks+info->groupbook;
 282   dim=look->phrasebook->dim;
 283
 284   look->partbooks=_ogg_calloc(look->parts,sizeof(*look->partbooks));
 285
 286   for(j=0;j<look->parts;j++){
 287     int stages=ilog(info->secondstages[j]);
 288     if(stages){
 289       if(stages>maxstage)maxstage=stages;
 290       look->partbooks[j]=_ogg_calloc(stages,sizeof(*look->partbooks[j]));
 291       for(k=0;k<stages;k++)
 292         if(info->secondstages[j]&(1<<k)){
 293           look->partbooks[j][k]=ci->fullbooks+info->booklist[acc++];
 294 #ifdef TRAIN_RES
 295           look->training_data[k][j]=_ogg_calloc(look->partbooks[j][k]->entries,
 296                                            sizeof(***look->training_data));
 297 #endif
 298         }
 299     }
 300   }
 301
 302   look->partvals=1;
 303   for(j=0;j<dim;j++)
 304       look->partvals*=look->parts;
 305
 306   look->stages=maxstage;
 307   look->decodemap=_ogg_malloc(look->partvals*sizeof(*look->decodemap));
 308   for(j=0;j<look->partvals;j++){
 309     long val=j;
 310     long mult=look->partvals/look->parts;
 311     look->decodemap[j]=_ogg_malloc(dim*sizeof(*look->decodemap[j]));
 312     for(k=0;k<dim;k++){
 313       long deco=val/mult;
 314       val-=deco*mult;
 315       mult/=look->parts;
 316       look->decodemap[j][k]=deco;
 317     }
 318   }
 319 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
 320   {
 321     static int train_seq=0;
 322     look->train_seq=train_seq++;
 323   }
 324 #endif
 325   return(look);
 326 }
 327
 328 /* break an abstraction and copy some code for performance purposes */
 329 static int local_book_besterror(codebook *book,int *a){
 330   int dim=book->dim;
 331   int i,j,o;
 332   int minval=book->minval;
 333   int del=book->delta;
 334   int qv=book->quantvals;
 335   int ze=(qv>>1);
 336   int index=0;
 337   /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */
 338   int p[8]={0,0,0,0,0,0,0,0};
 339
 340   if(del!=1){
 341     for(i=0,o=dim;i<dim;i++){
 342       int v = (a[--o]-minval+(del>>1))/del;
 343       int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));
 344       index = index*qv+ (m<0?0:(m>=qv?qv-1:m));
 345       p[o]=v*del+minval;
 346     }
 347   }else{
 348     for(i=0,o=dim;i<dim;i++){
 349       int v = a[--o]-minval;
 350       int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));
 351       index = index*qv+ (m<0?0:(m>=qv?qv-1:m));
 352       p[o]=v*del+minval;
 353     }
 354   }
 355
 356   if(book->c->lengthlist[index]<=0){
 357     const static_codebook *c=book->c;
 358     int best=-1;
 359     /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */
 360     int e[8]={0,0,0,0,0,0,0,0};
 361     int maxval = book->minval + book->delta*(book->quantvals-1);
 362     for(i=0;i<book->entries;i++){
 363       if(c->lengthlist[i]>0){
 364         int this=0;
 365         for(j=0;j<dim;j++){
 366           int val=(e[j]-a[j]);
 367           this+=val*val;
 368         }
 369         if(best==-1 || this<best){
 370           memcpy(p,e,sizeof(p));
 371           best=this;
 372           index=i;
 373         }
 374       }
 375       /* assumes the value patterning created by the tools in vq/ */
 376       j=0;
 377       while(e[j]>=maxval)
 378         e[j++]=0;
 379       if(e[j]>=0)
 380         e[j]+=book->delta;
 381       e[j]= -e[j];
 382     }
 383   }
 384
 385   if(index>-1){
 386     for(i=0;i<dim;i++)
 387       *a++ -= p[i];
 388   }
 389
 390   return(index);
 391 }
 392
 393 static int _encodepart(oggpack_buffer *opb,int *vec, int n,
 394                        codebook *book,long *acc){
 395   int i,bits=0;
 396   int dim=book->dim;
 397   int step=n/dim;
 398
 399   for(i=0;i<step;i++){
 400     int entry=local_book_besterror(book,vec+i*dim);
 401
 402 #ifdef TRAIN_RES
 403     if(entry>=0)
 404       acc[entry]++;
 405 #endif
 406
 407     bits+=vorbis_book_encode(book,entry,opb);
 408
 409   }
 410
 411   return(bits);
 412 }
 413
 414 static long **_01class(vorbis_block *vb,vorbis_look_residue *vl,
 415                        int **in,int ch){
 416   long i,j,k;
 417   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 418   vorbis_info_residue0 *info=look->info;
 419
 420   /* move all this setup out later */
 421   int samples_per_partition=info->grouping;
 422   int possible_partitions=info->partitions;
 423   int n=info->end-info->begin;
 424
 425   int partvals=n/samples_per_partition;
 426   long **partword=_vorbis_block_alloc(vb,ch*sizeof(*partword));
 427   float scale=100./samples_per_partition;
 428
 429   /* we find the partition type for each partition of each
 430      channel.  We'll go back and do the interleaved encoding in a
 431      bit.  For now, clarity */
 432
 433   for(i=0;i<ch;i++){
 434     partword[i]=_vorbis_block_alloc(vb,n/samples_per_partition*sizeof(*partword[i]));
 435     memset(partword[i],0,n/samples_per_partition*sizeof(*partword[i]));
 436   }
 437
 438   for(i=0;i<partvals;i++){
 439     int offset=i*samples_per_partition+info->begin;
 440     for(j=0;j<ch;j++){
 441       int max=0;
 442       int ent=0;
 443       for(k=0;k<samples_per_partition;k++){
 444         if(abs(in[j][offset+k])>max)max=abs(in[j][offset+k]);
 445         ent+=abs(in[j][offset+k]);
 446       }
 447       ent*=scale;
 448
 449       for(k=0;k<possible_partitions-1;k++)
 450         if(max<=info->classmetric1[k] &&
 451            (info->classmetric2[k]<0 || ent<info->classmetric2[k]))
 452           break;
 453
 454       partword[j][i]=k;
 455     }
 456   }
 457
 458 #ifdef TRAIN_RESAUX
 459   {
 460     FILE *of;
 461     char buffer[80];
 462
 463     for(i=0;i<ch;i++){
 464       sprintf(buffer,"resaux_%d.vqd",look->train_seq);
 465       of=fopen(buffer,"a");
 466       for(j=0;j<partvals;j++)
 467         fprintf(of,"%ld, ",partword[i][j]);
 468       fprintf(of,"\n");
 469       fclose(of);
 470     }
 471   }
 472 #endif
 473   look->frames++;
 474
 475   return(partword);
 476 }
 477
 478 /* designed for stereo or other modes where the partition size is an
 479    integer multiple of the number of channels encoded in the current
 480    submap */
 481 static long **_2class(vorbis_block *vb,vorbis_look_residue *vl,int **in,
 482                       int ch){
 483   long i,j,k,l;
 484   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 485   vorbis_info_residue0 *info=look->info;
 486
 487   /* move all this setup out later */
 488   int samples_per_partition=info->grouping;
 489   int possible_partitions=info->partitions;
 490   int n=info->end-info->begin;
 491
 492   int partvals=n/samples_per_partition;
 493   long **partword=_vorbis_block_alloc(vb,sizeof(*partword));
 494
 495 #if defined(TRAIN_RES) || defined (TRAIN_RESAUX)
 496   FILE *of;
 497   char buffer[80];
 498 #endif
 499
 500   partword[0]=_vorbis_block_alloc(vb,partvals*sizeof(*partword[0]));
 501   memset(partword[0],0,partvals*sizeof(*partword[0]));
 502
 503   for(i=0,l=info->begin/ch;i<partvals;i++){
 504     int magmax=0;
 505     int angmax=0;
 506     for(j=0;j<samples_per_partition;j+=ch){
 507       if(abs(in[0][l])>magmax)magmax=abs(in[0][l]);
 508       for(k=1;k<ch;k++)
 509         if(abs(in[k][l])>angmax)angmax=abs(in[k][l]);
 510       l++;
 511     }
 512
 513     for(j=0;j<possible_partitions-1;j++)
 514       if(magmax<=info->classmetric1[j] &&
 515          angmax<=info->classmetric2[j])
 516         break;
 517
 518     partword[0][i]=j;
 519
 520   }
 521
 522 #ifdef TRAIN_RESAUX
 523   sprintf(buffer,"resaux_%d.vqd",look->train_seq);
 524   of=fopen(buffer,"a");
 525   for(i=0;i<partvals;i++)
 526     fprintf(of,"%ld, ",partword[0][i]);
 527   fprintf(of,"\n");
 528   fclose(of);
 529 #endif
 530
 531   look->frames++;
 532
 533   return(partword);
 534 }
 535
 536 static int _01forward(oggpack_buffer *opb,
 537                       vorbis_block *vb,vorbis_look_residue *vl,
 538                       int **in,int ch,
 539                       long **partword,
 540                       int (*encode)(oggpack_buffer *,int *,int,
 541                                     codebook *,long *),
 542                       int submap){
 543   long i,j,k,s;
 544   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 545   vorbis_info_residue0 *info=look->info;
 546
 547 #ifdef TRAIN_RES
 548   look->submap=submap;
 549 #endif
 550
 551   /* move all this setup out later */
 552   int samples_per_partition=info->grouping;
 553   int possible_partitions=info->partitions;
 554   int partitions_per_word=look->phrasebook->dim;
 555   int n=info->end-info->begin;
 556
 557   int partvals=n/samples_per_partition;
 558   long resbits[128];
 559   long resvals[128];
 560
 561 #ifdef TRAIN_RES
 562   for(i=0;i<ch;i++)
 563     for(j=info->begin;j<info->end;j++){
 564       if(in[i][j]>look->tmax)look->tmax=in[i][j];
 565       if(in[i][j]<look->tmin)look->tmin=in[i][j];
 566     }
 567 #endif
 568
 569   memset(resbits,0,sizeof(resbits));
 570   memset(resvals,0,sizeof(resvals));
 571
 572   /* we code the partition words for each channel, then the residual
 573      words for a partition per channel until we've written all the
 574      residual words for that partition word.  Then write the next
 575      partition channel words... */
 576
 577   for(s=0;s<look->stages;s++){
 578
 579     for(i=0;i<partvals;){
 580
 581       /* first we encode a partition codeword for each channel */
 582       if(s==0){
 583         for(j=0;j<ch;j++){
 584           long val=partword[j][i];
 585           for(k=1;k<partitions_per_word;k++){
 586             val*=possible_partitions;
 587             if(i+k<partvals)
 588               val+=partword[j][i+k];
 589           }
 590
 591           /* training hack */
 592           if(val<look->phrasebook->entries)
 593             look->phrasebits+=vorbis_book_encode(look->phrasebook,val,opb);
 594 #if 0 /*def TRAIN_RES*/
 595           else
 596             fprintf(stderr,"!");
 597 #endif
 598
 599         }
 600       }
 601
 602       /* now we encode interleaved residual values for the partitions */
 603       for(k=0;k<partitions_per_word && i<partvals;k++,i++){
 604         long offset=i*samples_per_partition+info->begin;
 605
 606         for(j=0;j<ch;j++){
 607           if(s==0)resvals[partword[j][i]]+=samples_per_partition;
 608           if(info->secondstages[partword[j][i]]&(1<<s)){
 609             codebook *statebook=look->partbooks[partword[j][i]][s];
 610             if(statebook){
 611               int ret;
 612               long *accumulator=NULL;
 613
 614 #ifdef TRAIN_RES
 615               accumulator=look->training_data[s][partword[j][i]];
 616               {
 617                 int l;
 618                 int *samples=in[j]+offset;
 619                 for(l=0;l<samples_per_partition;l++){
 620                   if(samples[l]<look->training_min[s][partword[j][i]])
 621                     look->training_min[s][partword[j][i]]=samples[l];
 622                   if(samples[l]>look->training_max[s][partword[j][i]])
 623                     look->training_max[s][partword[j][i]]=samples[l];
 624                 }
 625               }
 626 #endif
 627
 628               ret=encode(opb,in[j]+offset,samples_per_partition,
 629                          statebook,accumulator);
 630
 631               look->postbits+=ret;
 632               resbits[partword[j][i]]+=ret;
 633             }
 634           }
 635         }
 636       }
 637     }
 638   }
 639
 640   /*{
 641     long total=0;
 642     long totalbits=0;
 643     fprintf(stderr,"%d :: ",vb->mode);
 644     for(k=0;k<possible_partitions;k++){
 645     fprintf(stderr,"%ld/%1.2g, ",resvals[k],(float)resbits[k]/resvals[k]);
 646     total+=resvals[k];
 647     totalbits+=resbits[k];
 648     }
 649
 650     fprintf(stderr,":: %ld:%1.2g\n",total,(double)totalbits/total);
 651     }*/
 652
 653   return(0);
 654 }
 655
 656 /* a truncated packet here just means 'stop working'; it's not an error */
 657 static int _01inverse(vorbis_block *vb,vorbis_look_residue *vl,
 658                       float **in,int ch,
 659                       long (*decodepart)(codebook *, float *,
 660                                          oggpack_buffer *,int)){
 661
 662   long i,j,k,l,s;
 663   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 664   vorbis_info_residue0 *info=look->info;
 665
 666   /* move all this setup out later */
 667   int samples_per_partition=info->grouping;
 668   int partitions_per_word=look->phrasebook->dim;
 669   int max=vb->pcmend>>1;
 670   int end=(info->end<max?info->end:max);
 671   int n=end-info->begin;
 672
 673   if(n>0){
 674     int partvals=n/samples_per_partition;
 675     int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 676     int ***partword=alloca(ch*sizeof(*partword));
 677
 678     for(j=0;j<ch;j++)
 679       partword[j]=_vorbis_block_alloc(vb,partwords*sizeof(*partword[j]));
 680
 681     for(s=0;s<look->stages;s++){
 682
 683       /* each loop decodes on partition codeword containing
 684          partitions_per_word partitions */
 685       for(i=0,l=0;i<partvals;l++){
 686         if(s==0){
 687           /* fetch the partition word for each channel */
 688           for(j=0;j<ch;j++){
 689             int temp=vorbis_book_decode(look->phrasebook,&vb->opb);
 690
 691             if(temp==-1 || temp>=info->partvals)goto eopbreak;
 692             partword[j][l]=look->decodemap[temp];
 693             if(partword[j][l]==NULL)goto errout;
 694           }
 695         }
 696
 697         /* now we decode residual values for the partitions */
 698         for(k=0;k<partitions_per_word && i<partvals;k++,i++)
 699           for(j=0;j<ch;j++){
 700             long offset=info->begin+i*samples_per_partition;
 701             if(info->secondstages[partword[j][l][k]]&(1<<s)){
 702               codebook *stagebook=look->partbooks[partword[j][l][k]][s];
 703               if(stagebook){
 704                 if(decodepart(stagebook,in[j]+offset,&vb->opb,
 705                               samples_per_partition)==-1)goto eopbreak;
 706               }
 707             }
 708           }
 709       }
 710     }
 711   }
 712  errout:
 713  eopbreak:
 714   return(0);
 715 }
 716
 717 int res0_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 718                  float **in,int *nonzero,int ch){
 719   int i,used=0;
 720   for(i=0;i<ch;i++)
 721     if(nonzero[i])
 722       in[used++]=in[i];
 723   if(used)
 724     return(_01inverse(vb,vl,in,used,vorbis_book_decodevs_add));
 725   else
 726     return(0);
 727 }
 728
 729 int res1_forward(oggpack_buffer *opb,vorbis_block *vb,vorbis_look_residue *vl,
 730                  int **in,int *nonzero,int ch, long **partword, int submap){
 731   int i,used=0;
 732   for(i=0;i<ch;i++)
 733     if(nonzero[i])
 734       in[used++]=in[i];
 735
 736   if(used){
 737     return _01forward(opb,vb,vl,in,used,partword,_encodepart,submap);
 738   }else{
 739     return(0);
 740   }
 741 }
 742
 743 long **res1_class(vorbis_block *vb,vorbis_look_residue *vl,
 744                   int **in,int *nonzero,int ch){
 745   int i,used=0;
 746   for(i=0;i<ch;i++)
 747     if(nonzero[i])
 748       in[used++]=in[i];
 749   if(used)
 750     return(_01class(vb,vl,in,used));
 751   else
 752     return(0);
 753 }
 754
 755 int res1_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 756                  float **in,int *nonzero,int ch){
 757   int i,used=0;
 758   for(i=0;i<ch;i++)
 759     if(nonzero[i])
 760       in[used++]=in[i];
 761   if(used)
 762     return(_01inverse(vb,vl,in,used,vorbis_book_decodev_add));
 763   else
 764     return(0);
 765 }
 766
 767 long **res2_class(vorbis_block *vb,vorbis_look_residue *vl,
 768                   int **in,int *nonzero,int ch){
 769   int i,used=0;
 770   for(i=0;i<ch;i++)
 771     if(nonzero[i])used++;
 772   if(used)
 773     return(_2class(vb,vl,in,ch));
 774   else
 775     return(0);
 776 }
 777
 778 /* res2 is slightly more different; all the channels are interleaved
 779    into a single vector and encoded. */
 780
 781 int res2_forward(oggpack_buffer *opb,
 782                  vorbis_block *vb,vorbis_look_residue *vl,
 783                  int **in,int *nonzero,int ch, long **partword,int submap){
 784   long i,j,k,n=vb->pcmend/2,used=0;
 785
 786   /* don't duplicate the code; use a working vector hack for now and
 787      reshape ourselves into a single channel res1 */
 788   /* ugly; reallocs for each coupling pass :-( */
 789   int *work=_vorbis_block_alloc(vb,ch*n*sizeof(*work));
 790   for(i=0;i<ch;i++){
 791     int *pcm=in[i];
 792     if(nonzero[i])used++;
 793     for(j=0,k=i;j<n;j++,k+=ch)
 794       work[k]=pcm[j];
 795   }
 796
 797   if(used){
 798     return _01forward(opb,vb,vl,&work,1,partword,_encodepart,submap);
 799   }else{
 800     return(0);
 801   }
 802 }
 803
 804 /* duplicate code here as speed is somewhat more important */
 805 int res2_inverse(vorbis_block *vb,vorbis_look_residue *vl,
 806                  float **in,int *nonzero,int ch){
 807   long i,k,l,s;
 808   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 809   vorbis_info_residue0 *info=look->info;
 810
 811   /* move all this setup out later */
 812   int samples_per_partition=info->grouping;
 813   int partitions_per_word=look->phrasebook->dim;
 814   int max=(vb->pcmend*ch)>>1;
 815   int end=(info->end<max?info->end:max);
 816   int n=end-info->begin;
 817
 818   if(n>0){
 819     int partvals=n/samples_per_partition;
 820     int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 821     int **partword=_vorbis_block_alloc(vb,partwords*sizeof(*partword));
 822
 823     for(i=0;i<ch;i++)if(nonzero[i])break;
 824     if(i==ch)return(0); /* no nonzero vectors */
 825
 826     for(s=0;s<look->stages;s++){
 827       for(i=0,l=0;i<partvals;l++){
 828
 829         if(s==0){
 830           /* fetch the partition word */
 831           int temp=vorbis_book_decode(look->phrasebook,&vb->opb);
 832           if(temp==-1 || temp>=info->partvals)goto eopbreak;
 833           partword[l]=look->decodemap[temp];
 834           if(partword[l]==NULL)goto errout;
 835         }
 836
 837         /* now we decode residual values for the partitions */
 838         for(k=0;k<partitions_per_word && i<partvals;k++,i++)
 839           if(info->secondstages[partword[l][k]]&(1<<s)){
 840             codebook *stagebook=look->partbooks[partword[l][k]][s];
 841
 842             if(stagebook){
 843               if(vorbis_book_decodevv_add(stagebook,in,
 844                                           i*samples_per_partition+info->begin,ch,
 845                                           &vb->opb,samples_per_partition)==-1)
 846                 goto eopbreak;
 847             }
 848           }
 849       }
 850     }
 851   }
 852  errout:
 853  eopbreak:
 854   return(0);
 855 }
 856
 857
 858 const vorbis_func_residue residue0_exportbundle={
 859   NULL,
 860   &res0_unpack,
 861   &res0_look,
 862   &res0_free_info,
 863   &res0_free_look,
 864   NULL,
 865   NULL,
 866   &res0_inverse
 867 };
 868
 869 const vorbis_func_residue residue1_exportbundle={
 870   &res0_pack,
 871   &res0_unpack,
 872   &res0_look,
 873   &res0_free_info,
 874   &res0_free_look,
 875   &res1_class,
 876   &res1_forward,
 877   &res1_inverse
 878 };
 879
 880 const vorbis_func_residue residue2_exportbundle={
 881   &res0_pack,
 882   &res0_unpack,
 883   &res0_look,
 884   &res0_free_info,
 885   &res0_free_look,
 886   &res2_class,
 887   &res2_forward,
 888   &res2_inverse
 889 };