/********************************************************************

 *                                                                  *

 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *

 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *

 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *

 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *

 *                                                                  *

 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2010             *

 * by the Xiph.Org Foundation https://xiph.org/                     *

 *                                                                  *

 ********************************************************************

 function: residue backend 0, 1 and 2 implementation

 ********************************************************************/

/* Slow, slow, slow, simpleminded and did I mention it was slow?  The

   encode/decode loops are coded for clarity and performance is not

   yet even a nagging little idea lurking in the shadows.  Oh and BTW,

   it's slow. */

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <ogg/ogg.h>

#include "vorbis/codec.h"

#include "codec_internal.h"

#include "registry.h"

#include "codebook.h"

#include "misc.h"

#include "os.h"

#if defined(TRAIN_RES) || defined (TRAIN_RESAUX)

#include <stdio.h>

#endif

typedef struct {

  vorbis_info_residue0 *info;

  int            parts;

  int            stages;

  codebook      *fullbooks;

  dec_codebook  *decbooks;

  int            phrasebook;

  int          **partbooks;

  int            partvals;

  int          **decodemap;

  long           postbits;

  long           phrasebits;

  long           frames;

#if defined(TRAIN_RES) || defined(TRAIN_RESAUX)

  int            train_seq;

  long          *training_data[8][64];

  float          training_max[8][64];

  float          training_min[8][64];

  float          tmin;

  float          tmax;

  int            submap;

#endif

} vorbis_look_residue0;

void res0_free_info(vorbis_info_residue *i){

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)i;

  if(info){

    memset(info,0,sizeof(*info));

    _ogg_free(info);

  }

}

void res0_free_look(vorbis_look_residue *i){

  int j;

  if(i){

    vorbis_look_residue0 *look=(vorbis_look_residue0 *)i;

#ifdef TRAIN_RES

    {

      int j,k,l;

      for(j=0;j<look->parts;j++){

        /*fprintf(stderr,"partition %d: ",j);*/

        for(k=0;k<8;k++)

          if(look->training_data[k][j]){

            char buffer[80];

            FILE *of;

            codebook *statebook=look->fullbooks+look->partbooks[j][k];

            /* long and short into the same bucket by current convention */

            sprintf(buffer,"res_sub%d_part%d_pass%d.vqd",look->submap,j,k);

            of=fopen(buffer,"a");

            for(l=0;l<statebook->entries;l++)

              fprintf(of,"%d:%ld\n",l,look->training_data[k][j][l]);

            fclose(of);

            /*fprintf(stderr,"%d(%.2f|%.2f) ",k,

              look->training_min[k][j],look->training_max[k][j]);*/

            _ogg_free(look->training_data[k][j]);

            look->training_data[k][j]=NULL;

          }

        /*fprintf(stderr,"\n");*/

      }

    }

    fprintf(stderr,"min/max residue: %g::%g\n",look->tmin,look->tmax);

    /*fprintf(stderr,"residue bit usage %f:%f (%f total)\n",

            (float)look->phrasebits/look->frames,

            (float)look->postbits/look->frames,

            (float)(look->postbits+look->phrasebits)/look->frames);*/

#endif

    /*vorbis_info_residue0 *info=look->info;

    fprintf(stderr,

            "%ld frames encoded in %ld phrasebits and %ld residue bits "

            "(%g/frame) \n",look->frames,look->phrasebits,

            look->resbitsflat,

            (look->phrasebits+look->resbitsflat)/(float)look->frames);

    for(j=0;j<look->parts;j++){

      long acc=0;

      fprintf(stderr,"\t[%d] == ",j);

      for(k=0;k<look->stages;k++)

        if((info->secondstages[j]>>k)&1){

          fprintf(stderr,"%ld,",look->resbits[j][k]);

          acc+=look->resbits[j][k];

        }

      fprintf(stderr,":: (%ld vals) %1.2fbits/sample\n",look->resvals[j],

              acc?(float)acc/(look->resvals[j]*info->grouping):0);

    }

    fprintf(stderr,"\n");*/

    for(j=0;j<look->parts;j++)

      if(look->partbooks[j])_ogg_free(look->partbooks[j]);

    _ogg_free(look->partbooks);

    for(j=0;j<look->partvals;j++)

      _ogg_free(look->decodemap[j]);

    _ogg_free(look->decodemap);

    memset(look,0,sizeof(*look));

    _ogg_free(look);

  }

}

static int icount(unsigned int v){

  int ret=0;

  while(v){

    ret+=v&1;

    v>>=1;

  }

  return(ret);

}

void res0_pack(vorbis_info_residue *vr,oggpack_buffer *opb){

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;

  int j,acc=0;

  oggpack_write(opb,info->begin,24);

  oggpack_write(opb,info->end,24);

  oggpack_write(opb,info->grouping-1,24);  /* residue vectors to group and

                                             code with a partitioned book */

  oggpack_write(opb,info->partitions-1,6); /* possible partition choices */

  oggpack_write(opb,info->groupbook,8);  /* group huffman book */

  /* secondstages is a bitmask; as encoding progresses pass by pass, a

     bitmask of one indicates this partition class has bits to write

     this pass */

  for(j=0;j<info->partitions;j++){

    if(ov_ilog(info->secondstages[j])>3){

      /* yes, this is a minor hack due to not thinking ahead */

      oggpack_write(opb,info->secondstages[j],3);

      oggpack_write(opb,1,1);

      oggpack_write(opb,info->secondstages[j]>>3,5);

    }else

      oggpack_write(opb,info->secondstages[j],4); /* trailing zero */

    acc+=icount(info->secondstages[j]);

  }

  for(j=0;j<acc;j++)

    oggpack_write(opb,info->booklist[j],8);

}

/* vorbis_info is for range checking */

vorbis_info_residue *res0_unpack(vorbis_info *vi,oggpack_buffer *opb){

  int j,acc=0;

  vorbis_info_residue0 *info=_ogg_calloc(1,sizeof(*info));

  codec_setup_info     *ci=vi->codec_setup;

  info->begin=oggpack_read(opb,24);

  info->end=oggpack_read(opb,24);

  info->grouping=oggpack_read(opb,24)+1;

  info->partitions=oggpack_read(opb,6)+1;

  info->groupbook=oggpack_read(opb,8);

  /* check for premature EOP */

  if(info->groupbook<0)goto errout;

  for(j=0;j<info->partitions;j++){

    int cascade=oggpack_read(opb,3);

    int cflag=oggpack_read(opb,1);

    if(cflag<0) goto errout;

    if(cflag){

      int c=oggpack_read(opb,5);

      if(c<0) goto errout;

      cascade|=(c<<3);

    }

    info->secondstages[j]=cascade;

    acc+=icount(cascade);

  }

  for(j=0;j<acc;j++){

    int book=oggpack_read(opb,8);

    if(book<0) goto errout;

    info->booklist[j]=book;

  }

  if(info->groupbook>=ci->books)goto errout;

  for(j=0;j<acc;j++){

    if(info->booklist[j]>=ci->books)goto errout;

    if(ci->decbooks[info->booklist[j]].maptype==0)goto errout;

  }

  /* verify the phrasebook is not specifying an impossible or

     inconsistent partitioning scheme. */

  /* modify the phrasebook ranging check from r16327; an early beta

     encoder had a bug where it used an oversized phrasebook by

     accident.  These files should continue to be playable, but don't

     allow an exploit */

  {

    int entries = ci->decbooks[info->groupbook].entries;

    int dim = ci->decbooks[info->groupbook].dim;

    int partvals = 1;

    if (dim<1) goto errout;

    while(dim>0){

      partvals *= info->partitions;

      if(partvals > entries) goto errout;

      dim--;

    }

    info->partvals = partvals;

  }

  return(info);

 errout:

  res0_free_info(info);

  return(NULL);

}

vorbis_look_residue *res0_look(vorbis_dsp_state *vd,

                               vorbis_info_residue *vr){

  vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;

  vorbis_look_residue0 *look=_ogg_calloc(1,sizeof(*look));

  codec_setup_info     *ci=vd->vi->codec_setup;

  int j,k,acc=0;

  int dim;

  int maxstage=0;

  look->info=info;

  look->parts=info->partitions;

  look->fullbooks=ci->fullbooks;

  look->decbooks=ci->decbooks;

  look->phrasebook=info->groupbook;

  dim=look->fullbooks?

   look->fullbooks[look->phrasebook].dim:look->decbooks[look->phrasebook].dim;

  look->partbooks=_ogg_calloc(look->parts,sizeof(*look->partbooks));

  for(j=0;j<look->parts;j++){

    int stages=ov_ilog(info->secondstages[j]);

    if(stages){

      if(stages>maxstage)maxstage=stages;

      look->partbooks[j]=_ogg_calloc(stages,sizeof(*look->partbooks[j]));

      for(k=0;k<stages;k++)

        if(info->secondstages[j]&(1<<k)){

          look->partbooks[j][k]=info->booklist[acc++];

#ifdef TRAIN_RES

          look->training_data[k][j]=_ogg_calloc(

           look->fullbooks[look->partbooks[j][k]].entries,

           sizeof(***look->training_data));

#endif

        }else{

          look->partbooks[j][k]=-1;

        }

    }

  }

  look->partvals=1;

  for(j=0;j<dim;j++)

      look->partvals*=look->parts;

  look->stages=maxstage;

  look->decodemap=_ogg_malloc(look->partvals*sizeof(*look->decodemap));

  for(j=0;j<look->partvals;j++){

    long val=j;

    long mult=look->partvals/look->parts;

    look->decodemap[j]=_ogg_malloc(dim*sizeof(*look->decodemap[j]));

    for(k=0;k<dim;k++){

      long deco=val/mult;

      val-=deco*mult;

      mult/=look->parts;

      look->decodemap[j][k]=deco;

    }

  }

#if defined(TRAIN_RES) || defined (TRAIN_RESAUX)

  {

    static int train_seq=0;

    look->train_seq=train_seq++;

  }

#endif

  return(look);

}

/* break an abstraction and copy some code for performance purposes */

static int local_book_besterror(codebook *book,int *a){

  int dim=book->dim;

  int i,j,o;

  int minval=book->minval;

  int del=book->delta;

  int qv=book->quantvals;

  int ze=(qv>>1);

  int index=0;

  /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */

  int p[8]={0,0,0,0,0,0,0,0};

  if(del!=1){

    for(i=0,o=dim;i<dim;i++){

      int v = (a[--o]-minval+(del>>1))/del;

      int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));

      index = index*qv+ (m<0?0:(m>=qv?qv-1:m));

      p[o]=v*del+minval;

    }

  }else{

    for(i=0,o=dim;i<dim;i++){

      int v = a[--o]-minval;

      int m = (v<ze ? ((ze-v)<<1)-1 : ((v-ze)<<1));

      index = index*qv+ (m<0?0:(m>=qv?qv-1:m));

      p[o]=v*del+minval;

    }

  }

  if(book->c->lengthlist[index]<=0){

    const static_codebook *c=book->c;

    int best=-1;

    /* assumes integer/centered encoder codebook maptype 1 no more than dim 8 */

    int e[8]={0,0,0,0,0,0,0,0};

    int maxval = book->minval + book->delta*(book->quantvals-1);

    for(i=0;i<book->entries;i++){

      if(c->lengthlist[i]>0){

        int this=0;

        for(j=0;j<dim;j++){

          int val=(e[j]-a[j]);

          this+=val*val;

        }

        if(best==-1 || this<best){

          memcpy(p,e,sizeof(p));

          best=this;

          index=i;

        }

      }

      /* assumes the value patterning created by the tools in vq/ */

      j=0;

      while(e[j]>=maxval)

        e[j++]=0;

      if(e[j]>=0)

        e[j]+=book->delta;

      e[j]= -e[j];

    }

  }

  if(index>-1){

    for(i=0;i<dim;i++)

      *a++ -= p[i];

  }

  return(index);

}

#ifdef TRAIN_RES

static int _encodepart(oggpack_buffer *opb,int *vec, int n,

                       codebook *book,long *acc){

#else

static int _encodepart(oggpack_buffer *opb,int *vec, int n,

                       codebook *book){

#endif

  int i,bits=0;

  int dim=book->dim;

  int step=n/dim;

  for(i=0;i<step;i++){

    int entry=local_book_besterror(book,vec+i*dim);

#ifdef TRAIN_RES

    if(entry>=0)

      acc[entry]++;

#endif

    bits+=vorbis_book_encode(book,entry,opb);

  }

  return(bits);

}

static long **_01class(vorbis_block *vb,vorbis_look_residue *vl,

                       int **in,int ch){

  long i,j,k;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int possible_partitions=info->partitions;

  int n=info->end-info->begin;

  int partvals=n/samples_per_partition;

  long **partword=_vorbis_block_alloc(vb,ch*sizeof(*partword));

  float scale=100./samples_per_partition;

  /* we find the partition type for each partition of each

     channel.  We'll go back and do the interleaved encoding in a

     bit.  For now, clarity */

  for(i=0;i<ch;i++){

    partword[i]=_vorbis_block_alloc(vb,n/samples_per_partition*sizeof(*partword[i]));

    memset(partword[i],0,n/samples_per_partition*sizeof(*partword[i]));

  }

  for(i=0;i<partvals;i++){

    int offset=i*samples_per_partition+info->begin;

    for(j=0;j<ch;j++){

      int max=0;

      int ent=0;

      for(k=0;k<samples_per_partition;k++){

        if(abs(in[j][offset+k])>max)max=abs(in[j][offset+k]);

        ent+=abs(in[j][offset+k]);

      }

      ent*=scale;

      for(k=0;k<possible_partitions-1;k++)

        if(max<=info->classmetric1[k] &&

           (info->classmetric2[k]<0 || ent<info->classmetric2[k]))

          break;

      partword[j][i]=k;

    }

  }

#ifdef TRAIN_RESAUX

  {

    FILE *of;

    char buffer[80];

    for(i=0;i<ch;i++){

      sprintf(buffer,"resaux_%d.vqd",look->train_seq);

      of=fopen(buffer,"a");

      for(j=0;j<partvals;j++)

        fprintf(of,"%ld, ",partword[i][j]);

      fprintf(of,"\n");

      fclose(of);

    }

  }

#endif

  look->frames++;

  return(partword);

}

/* designed for stereo or other modes where the partition size is an

   integer multiple of the number of channels encoded in the current

   submap */

static long **_2class(vorbis_block *vb,vorbis_look_residue *vl,int **in,

                      int ch){

  long i,j,k,l;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int possible_partitions=info->partitions;

  int n=info->end-info->begin;

  int partvals=n/samples_per_partition;

  long **partword=_vorbis_block_alloc(vb,sizeof(*partword));

#if defined(TRAIN_RES) || defined (TRAIN_RESAUX)

  FILE *of;

  char buffer[80];

#endif

  partword[0]=_vorbis_block_alloc(vb,partvals*sizeof(*partword[0]));

  memset(partword[0],0,partvals*sizeof(*partword[0]));

  for(i=0,l=info->begin/ch;i<partvals;i++){

    int magmax=0;

    int angmax=0;

    for(j=0;j<samples_per_partition;j+=ch){

      if(abs(in[0][l])>magmax)magmax=abs(in[0][l]);

      for(k=1;k<ch;k++)

        if(abs(in[k][l])>angmax)angmax=abs(in[k][l]);

      l++;

    }

    for(j=0;j<possible_partitions-1;j++)

      if(magmax<=info->classmetric1[j] &&

         angmax<=info->classmetric2[j])

        break;

    partword[0][i]=j;

  }

#ifdef TRAIN_RESAUX

  sprintf(buffer,"resaux_%d.vqd",look->train_seq);

  of=fopen(buffer,"a");

  for(i=0;i<partvals;i++)

    fprintf(of,"%ld, ",partword[0][i]);

  fprintf(of,"\n");

  fclose(of);

#endif

  look->frames++;

  return(partword);

}

static int _01forward(oggpack_buffer *opb,

                      vorbis_look_residue *vl,

                      int **in,int ch,

                      long **partword,

#ifdef TRAIN_RES

                      int (*encode)(oggpack_buffer *,int *,int,

                                    codebook *,long *),

                      int submap

#else

                      int (*encode)(oggpack_buffer *,int *,int,

                                    codebook *)

#endif

){

  long i,j,k,s;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  codebook *phrasebook=look->fullbooks+look->phrasebook;

#ifdef TRAIN_RES

  look->submap=submap;

#endif

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int possible_partitions=info->partitions;

  int partitions_per_word=phrasebook->dim;

  int n=info->end-info->begin;

  int partvals=n/samples_per_partition;

  long resbits[128];

  long resvals[128];

#ifdef TRAIN_RES

  for(i=0;i<ch;i++)

    for(j=info->begin;j<info->end;j++){

      if(in[i][j]>look->tmax)look->tmax=in[i][j];

      if(in[i][j]<look->tmin)look->tmin=in[i][j];

    }

#endif

  memset(resbits,0,sizeof(resbits));

  memset(resvals,0,sizeof(resvals));

  /* we code the partition words for each channel, then the residual

     words for a partition per channel until we've written all the

     residual words for that partition word.  Then write the next

     partition channel words... */

  for(s=0;s<look->stages;s++){

    for(i=0;i<partvals;){

      /* first we encode a partition codeword for each channel */

      if(s==0){

        for(j=0;j<ch;j++){

          long val=partword[j][i];

          for(k=1;k<partitions_per_word;k++){

            val*=possible_partitions;

            if(i+k<partvals)

              val+=partword[j][i+k];

          }

          /* training hack */

          if(val<phrasebook->entries)

            look->phrasebits+=vorbis_book_encode(phrasebook,val,opb);

#if 0 /*def TRAIN_RES*/

          else

            fprintf(stderr,"!");

#endif

        }

      }

      /* now we encode interleaved residual values for the partitions */

      for(k=0;k<partitions_per_word && i<partvals;k++,i++){

        long offset=i*samples_per_partition+info->begin;

        for(j=0;j<ch;j++){

          if(s==0)resvals[partword[j][i]]+=samples_per_partition;

          if(info->secondstages[partword[j][i]]&(1<<s)){

            int statebooknum=look->partbooks[partword[j][i]][s];

            if(statebooknum>=0){

              codebook *statebook=look->fullbooks+statebooknum;

              int ret;

#ifdef TRAIN_RES

              long *accumulator=NULL;

              accumulator=look->training_data[s][partword[j][i]];

              {

                int l;

                int *samples=in[j]+offset;

                for(l=0;l<samples_per_partition;l++){

                  if(samples[l]<look->training_min[s][partword[j][i]])

                    look->training_min[s][partword[j][i]]=samples[l];

                  if(samples[l]>look->training_max[s][partword[j][i]])

                    look->training_max[s][partword[j][i]]=samples[l];

                }

              }

              ret=encode(opb,in[j]+offset,samples_per_partition,

                         statebook,accumulator);

#else

              ret=encode(opb,in[j]+offset,samples_per_partition,

                         statebook);

#endif

              look->postbits+=ret;

              resbits[partword[j][i]]+=ret;

            }

          }

        }

      }

    }

  }

  return(0);

}

/* a truncated packet here just means 'stop working'; it's not an error */

static int _01inverse(vorbis_block *vb,vorbis_look_residue *vl,

                      float **in,int ch,

                      long (*decodepart)(dec_codebook *, float *,

                                         oggpack_buffer *,int)){

  long i,j,k,l,s;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  dec_codebook *phrasebook=look->decbooks+look->phrasebook;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int partitions_per_word=phrasebook->dim;

  int max=vb->pcmend>>1;

  int end=(info->end<max?info->end:max);

  int n=end-info->begin;

  if(n>0){

    int partvals=n/samples_per_partition;

    int partwords=(partvals+partitions_per_word-1)/partitions_per_word;

    int ***partword=alloca(ch*sizeof(*partword));

    for(j=0;j<ch;j++)

      partword[j]=_vorbis_block_alloc(vb,partwords*sizeof(*partword[j]));

    for(s=0;s<look->stages;s++){

      /* each loop decodes on partition codeword containing

         partitions_per_word partitions */

      for(i=0,l=0;i<partvals;l++){

        if(s==0){

          /* fetch the partition word for each channel */

          for(j=0;j<ch;j++){

            int temp=vorbis_book_decode(phrasebook,&vb->opb);

            if(temp==-1 || temp>=info->partvals)goto eopbreak;

            partword[j][l]=look->decodemap[temp];

            if(partword[j][l]==NULL)goto errout;

          }

        }

        /* now we decode residual values for the partitions */

        for(k=0;k<partitions_per_word && i<partvals;k++,i++)

          for(j=0;j<ch;j++){

            long offset=info->begin+i*samples_per_partition;

            if(info->secondstages[partword[j][l][k]]&(1<<s)){

              int stagebooknum=look->partbooks[partword[j][l][k]][s];

              if(stagebooknum>=0){

                dec_codebook *stagebook=look->decbooks+stagebooknum;

                if(decodepart(stagebook,in[j]+offset,&vb->opb,

                              samples_per_partition)==-1)goto eopbreak;

              }

            }

          }

      }

    }

  }

 errout:

 eopbreak:

  return(0);

}

int res0_inverse(vorbis_block *vb,vorbis_look_residue *vl,

                 float **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used)

    return(_01inverse(vb,vl,in,used,vorbis_book_decodevs_add));

  else

    return(0);

}

int res1_forward(oggpack_buffer *opb,vorbis_block *vb,vorbis_look_residue *vl,

                 int **in,int *nonzero,int ch, long **partword, int submap){

  int i,used=0;

  (void)vb;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used){

#ifdef TRAIN_RES

    return _01forward(opb,vl,in,used,partword,_encodepart,submap);

#else

    (void)submap;

    return _01forward(opb,vl,in,used,partword,_encodepart);

#endif

  }else{

    return(0);

  }

}

long **res1_class(vorbis_block *vb,vorbis_look_residue *vl,

                  int **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used)

    return(_01class(vb,vl,in,used));

  else

    return(0);

}

int res1_inverse(vorbis_block *vb,vorbis_look_residue *vl,

                 float **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])

      in[used++]=in[i];

  if(used)

    return(_01inverse(vb,vl,in,used,vorbis_book_decodev_add));

  else

    return(0);

}

long **res2_class(vorbis_block *vb,vorbis_look_residue *vl,

                  int **in,int *nonzero,int ch){

  int i,used=0;

  for(i=0;i<ch;i++)

    if(nonzero[i])used++;

  if(used)

    return(_2class(vb,vl,in,ch));

  else

    return(0);

}

/* res2 is slightly more different; all the channels are interleaved

   into a single vector and encoded. */

int res2_forward(oggpack_buffer *opb,

                 vorbis_block *vb,vorbis_look_residue *vl,

                 int **in,int *nonzero,int ch, long **partword,int submap){

  long i,j,k,n=vb->pcmend/2,used=0;

  /* don't duplicate the code; use a working vector hack for now and

     reshape ourselves into a single channel res1 */

  /* ugly; reallocs for each coupling pass :-( */

  int *work=_vorbis_block_alloc(vb,ch*n*sizeof(*work));

  for(i=0;i<ch;i++){

    int *pcm=in[i];

    if(nonzero[i])used++;

    for(j=0,k=i;j<n;j++,k+=ch)

      work[k]=pcm[j];

  }

  if(used){

#ifdef TRAIN_RES

    return _01forward(opb,vl,&work,1,partword,_encodepart,submap);

#else

    (void)submap;

    return _01forward(opb,vl,&work,1,partword,_encodepart);

#endif

  }else{

    return(0);

  }

}

/* duplicate code here as speed is somewhat more important */

int res2_inverse(vorbis_block *vb,vorbis_look_residue *vl,

                 float **in,int *nonzero,int ch){

  long i,k,l,s;

  vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;

  vorbis_info_residue0 *info=look->info;

  dec_codebook *phrasebook=look->decbooks+look->phrasebook;

  /* move all this setup out later */

  int samples_per_partition=info->grouping;

  int partitions_per_word=phrasebook->dim;

  int max=(vb->pcmend*ch)>>1;

  int end=(info->end<max?info->end:max);

  int n=end-info->begin;

  if(n>0){

    int partvals=n/samples_per_partition;

    int partwords=(partvals+partitions_per_word-1)/partitions_per_word;

    int **partword=_vorbis_block_alloc(vb,partwords*sizeof(*partword));

    for(i=0;i<ch;i++)if(nonzero[i])break;

    if(i==ch)return(0); /* no nonzero vectors */

    for(s=0;s<look->stages;s++){

      for(i=0,l=0;i<partvals;l++){

        if(s==0){

          /* fetch the partition word */

          int temp=vorbis_book_decode(phrasebook,&vb->opb);

          if(temp==-1 || temp>=info->partvals)goto eopbreak;

          partword[l]=look->decodemap[temp];

          if(partword[l]==NULL)goto errout;

        }

        /* now we decode residual values for the partitions */

        for(k=0;k<partitions_per_word && i<partvals;k++,i++)

          if(info->secondstages[partword[l][k]]&(1<<s)){

            int stagebooknum=look->partbooks[partword[l][k]][s];

            if(stagebooknum>=0){

              dec_codebook *stagebook=look->decbooks+stagebooknum;

              if(vorbis_book_decodevv_add(stagebook,in,

                                          i*samples_per_partition+info->begin,ch,

                                          &vb->opb,samples_per_partition)==-1)

                goto eopbreak;

            }

          }

      }

    }

  }

 errout:

 eopbreak:

  return(0);

}

const vorbis_func_residue residue0_exportbundle={

  NULL,

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  NULL,

  NULL,

  &res0_inverse

};

const vorbis_func_residue residue1_exportbundle={

  &res0_pack,

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  &res1_class,

  &res1_forward,

  &res1_inverse

};

const vorbis_func_residue residue2_exportbundle={

  &res0_pack,

  &res0_unpack,

  &res0_look,

  &res0_free_info,

  &res0_free_look,

  &res2_class,

  &res2_forward,

  &res2_inverse

};