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