vx32

res0.c (23187B)

---

 /********************************************************************
  *                                                                  *
  * 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 1994-2002             *
  * by the XIPHOPHORUS Company http://www.xiph.org/                  *
  *                                                                  *
  ********************************************************************
 
  function: residue backend 0, 1 and 2 implementation
  last mod: $Id: res0.c 1919 2005-07-24 14:18:04Z baford $
 
  ********************************************************************/
 
 /* 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"
 
 #ifdef TRAIN_RES
 #include <stdio.h>
 #endif 
 
 typedef struct {
   vorbis_info_residue0 *info;
   
   int         parts;
   int         stages;
   codebook   *fullbooks;
   codebook   *phrasebook;
   codebook ***partbooks;
 
   int         partvals;
   int       **decodemap;
 
   long      postbits;
   long      phrasebits;
   long      frames;
 
 #ifdef TRAIN_RES
   int        train_seq;
   long      *training_data[8][64];
   float      training_max[8][64];
   float      training_min[8][64];
   float     tmin;
   float     tmax;
 #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->partbooks[j][k];
 	    
 	    /* long and short into the same bucket by current convention */
 	    sprintf(buffer,"res_part%d_pass%d.vqd",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]);
 	  }
 	/*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 ilog(unsigned int v){
   int ret=0;
   while(v){
     ret++;
     v>>=1;
   }
   return(ret);
 }
 
 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(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);
 
   for(j=0;j<info->partitions;j++){
     int cascade=oggpack_read(opb,3);
     if(oggpack_read(opb,1))
       cascade|=(oggpack_read(opb,5)<<3);
     info->secondstages[j]=cascade;
 
     acc+=icount(cascade);
   }
   for(j=0;j<acc;j++)
     info->booklist[j]=oggpack_read(opb,8);
 
   if(info->groupbook>=ci->books)goto errout;
   for(j=0;j<acc;j++)
     if(info->booklist[j]>=ci->books)goto errout;
 
   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->phrasebook=ci->fullbooks+info->groupbook;
   dim=look->phrasebook->dim;
 
   look->partbooks=_ogg_calloc(look->parts,sizeof(*look->partbooks));
 
   for(j=0;j<look->parts;j++){
     int stages=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]=ci->fullbooks+info->booklist[acc++];
 #ifdef TRAIN_RES
 	  look->training_data[k][j]=calloc(look->partbooks[j][k]->entries,
 					   sizeof(***look->training_data));
 #endif
 	}
     }
   }
 
   look->partvals=rint(pow((float)look->parts,(float)dim));
   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;
     }
   }
 #ifdef TRAIN_RES
   {
     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,float *a){
   int dim=book->dim,i,k,o;
   int best=0;
   encode_aux_threshmatch *tt=book->c->thresh_tree;
 
   /* find the quant val of each scalar */
   for(k=0,o=dim;k<dim;++k){
     float val=a[--o];
     i=tt->threshvals>>1;
 
     if(val<tt->quantthresh[i]){      
       if(val<tt->quantthresh[i-1]){
 	for(--i;i>0;--i)
 	  if(val>=tt->quantthresh[i-1])
 	    break;
       }
     }else{
       
       for(++i;i<tt->threshvals-1;++i)
 	if(val<tt->quantthresh[i])break;
       
     }
     
     best=(best*tt->quantvals)+tt->quantmap[i];
   }
   /* regular lattices are easy :-) */
   
   if(book->c->lengthlist[best]<=0){
     const static_codebook *c=book->c;
     int i,j;
     float bestf=0.f;
     float *e=book->valuelist;
     best=-1;
     for(i=0;i<book->entries;i++){
       if(c->lengthlist[i]>0){
 	float this=0.f;
 	for(j=0;j<dim;j++){
 	  float val=(e[j]-a[j]);
 	  this+=val*val;
 	}
 	if(best==-1 || this<bestf){
 	  bestf=this;
 	  best=i;
 	}
       }
       e+=dim;
     }
   }
 
   {
     float *ptr=book->valuelist+best*dim;
     for(i=0;i<dim;i++)
       *a++ -= *ptr++;
   }
 
   return(best);
 }
 
 static int _encodepart(oggpack_buffer *opb,float *vec, int n,
 		       codebook *book,long *acc){
   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
     acc[entry]++;
 #endif
 
     bits+=vorbis_book_encode(book,entry,opb);
   }
 
   return(bits);
 }
 
 static long **_01class(vorbis_block *vb,vorbis_look_residue *vl,
 		       float **in,int ch){
   long i,j,k;
   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
   vorbis_info_residue0 *info=look->info;
   vorbis_info           *vi=vb->vd->vi;
   codec_setup_info      *ci=vi->codec_setup;
 
   /* 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++){
       float max=0.;
       float ent=0.;
       for(k=0;k<samples_per_partition;k++){
 	if(fabs(in[j][offset+k])>max)max=fabs(in[j][offset+k]);
 	ent+=fabs(rint(in[j][offset+k]));
       }
       ent*=scale;
       
       for(k=0;k<possible_partitions-1;k++)
 	if(max<=info->classmetric1[k] &&
 	   (info->classmetric2[k]<0 || (int)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,float **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));
 
 #ifdef TRAIN_RES
   FILE *of;
   char buffer[80];
 #endif
   
   partword[0]=_vorbis_block_alloc(vb,n*ch/samples_per_partition*sizeof(*partword[0]));
   memset(partword[0],0,n*ch/samples_per_partition*sizeof(*partword[0]));
 
   for(i=0,l=info->begin/ch;i<partvals;i++){
     float magmax=0.f;
     float angmax=0.f;
     for(j=0;j<samples_per_partition;j+=ch){
       if(fabs(in[0][l])>magmax)magmax=fabs(in[0][l]);
       for(k=1;k<ch;k++)
 	if(fabs(in[k][l])>angmax)angmax=fabs(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(vorbis_block *vb,vorbis_look_residue *vl,
 		      float **in,int ch,
 		      long **partword,
 		      int (*encode)(oggpack_buffer *,float *,int,
 				    codebook *,long *)){
   long i,j,k,s;
   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
   vorbis_info_residue0 *info=look->info;
 
   vorbis_dsp_state      *vd=vb->vd;
 
   /* move all this setup out later */
   int samples_per_partition=info->grouping;
   int possible_partitions=info->partitions;
   int partitions_per_word=look->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<look->phrasebook->entries)
 	    look->phrasebits+=vorbis_book_encode(look->phrasebook,val,&vb->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)){
 	    codebook *statebook=look->partbooks[partword[j][i]][s];
 	    if(statebook){
 	      int ret;
 	      long *accumulator=NULL;
 
 #ifdef TRAIN_RES
 	      accumulator=look->training_data[s][partword[j][i]];
 	      {
 		int l;
 		float *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];
 		}
 	      }
 #endif
 	      
 	      ret=encode(&vb->opb,in[j]+offset,samples_per_partition,
 			 statebook,accumulator);
 
 	      look->postbits+=ret;
 	      resbits[partword[j][i]]+=ret;
 	    }
 	  }
 	}
       }
     }
   }
 
   /*{
     long total=0;
     long totalbits=0;
     fprintf(stderr,"%d :: ",vb->mode);
     for(k=0;k<possible_partitions;k++){
       fprintf(stderr,"%ld/%1.2g, ",resvals[k],(float)resbits[k]/resvals[k]);
       total+=resvals[k];
       totalbits+=resbits[k];
       }
     
     fprintf(stderr,":: %ld:%1.2g\n",total,(double)totalbits/total);
     }*/
   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)(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;
 
   /* move all this setup out later */
   int samples_per_partition=info->grouping;
   int partitions_per_word=look->phrasebook->dim;
   int n=info->end-info->begin;
   
   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_pre_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(look->phrasebook,&vb->opb);
 	  if(temp==-1)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)){
 	    codebook *stagebook=look->partbooks[partword[j][l][k]][s];
 	    if(stagebook){
 	      if(decodepart(stagebook,in[j]+offset,&vb->opb,
 			    samples_per_partition)==-1)goto eopbreak;
 	    }
 	  }
 	}
     } 
   }
   
  errout:
  eopbreak:
   return(0);
 }
 
 #if 0
 /* residue 0 and 1 are just slight variants of one another. 0 is
    interleaved, 1 is not */
 long **res0_class(vorbis_block *vb,vorbis_look_residue *vl,
 		  float **in,int *nonzero,int ch){
   /* we encode only the nonzero parts of a bundle */
   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,_interleaved_testhack));*/
     return(_01class(vb,vl,in,used));
   else
     return(0);
 }
 
 int res0_forward(vorbis_block *vb,vorbis_look_residue *vl,
 		 float **in,float **out,int *nonzero,int ch,
 		 long **partword){
   /* we encode only the nonzero parts of a bundle */
   int i,j,used=0,n=vb->pcmend/2;
   for(i=0;i<ch;i++)
     if(nonzero[i]){
       if(out)
 	for(j=0;j<n;j++)
 	  out[i][j]+=in[i][j];
       in[used++]=in[i];
     }
   if(used){
     int ret=_01forward(vb,vl,in,used,partword,
 		      _interleaved_encodepart);
     if(out){
       used=0;
       for(i=0;i<ch;i++)
 	if(nonzero[i]){
 	  for(j=0;j<n;j++)
 	    out[i][j]-=in[used][j];
 	  used++;
 	}
     }
     return(ret);
   }else{
     return(0);
   }
 }
 #endif
 
 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(vorbis_block *vb,vorbis_look_residue *vl,
 		 float **in,float **out,int *nonzero,int ch,
 		 long **partword){
   int i,j,used=0,n=vb->pcmend/2;
   for(i=0;i<ch;i++)
     if(nonzero[i]){
       if(out)
 	for(j=0;j<n;j++)
 	  out[i][j]+=in[i][j];
       in[used++]=in[i];
     }
 
   if(used){
     int ret=_01forward(vb,vl,in,used,partword,_encodepart);
     if(out){
       used=0;
       for(i=0;i<ch;i++)
 	if(nonzero[i]){
 	  for(j=0;j<n;j++)
 	    out[i][j]-=in[used][j];
 	  used++;
 	}
     }
     return(ret);
   }else{
     return(0);
   }
 }
 
 long **res1_class(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(_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,
 		  float **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(vorbis_block *vb,vorbis_look_residue *vl,
 		 float **in,float **out,int *nonzero,int ch,
 		 long **partword){
   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 :-( */
   float *work=_vorbis_block_alloc(vb,ch*n*sizeof(*work));
   for(i=0;i<ch;i++){
     float *pcm=in[i];
     if(nonzero[i])used++;
     for(j=0,k=i;j<n;j++,k+=ch)
       work[k]=pcm[j];
   }
   
   if(used){
     int ret=_01forward(vb,vl,&work,1,partword,_encodepart);
     /* update the sofar vector */
     if(out){
       for(i=0;i<ch;i++){
 	float *pcm=in[i];
 	float *sofar=out[i];
 	for(j=0,k=i;j<n;j++,k+=ch)
 	  sofar[j]+=pcm[j]-work[k];
 	
       }
     }
     return(ret);
   }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;
 
   /* move all this setup out later */
   int samples_per_partition=info->grouping;
   int partitions_per_word=look->phrasebook->dim;
   int n=info->end-info->begin;
 
   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(look->phrasebook,&vb->opb);
 	if(temp==-1)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)){
 	  codebook *stagebook=look->partbooks[partword[l][k]][s];
 	  
 	  if(stagebook){
 	    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);
 }
 
 
 vorbis_func_residue residue0_exportbundle={
   NULL,
   &res0_unpack,
   &res0_look,
   &res0_free_info,
   &res0_free_look,
   NULL,
   NULL,
   &res0_inverse
 };
 
 vorbis_func_residue residue1_exportbundle={
   &res0_pack,
   &res0_unpack,
   &res0_look,
   &res0_free_info,
   &res0_free_look,
   &res1_class,
   &res1_forward,
   &res1_inverse
 };
 
 vorbis_func_residue residue2_exportbundle={
   &res0_pack,
   &res0_unpack,
   &res0_look,
   &res0_free_info,
   &res0_free_look,
   &res2_class,
   &res2_forward,
   &res2_inverse
 };