lib/res0.c

   1 /********************************************************************
   2  *                                                                  *
   3  * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE.  *
   4  * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
   5  * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE.    *
   6  * PLEASE READ THESE TERMS DISTRIBUTING.                            *
   7  *                                                                  *
   8  * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000             *
   9  * by Monty <monty@xiph.org> and The XIPHOPHORUS Company            *
  10  * http://www.xiph.org/                                             *
  11  *                                                                  *
  12  ********************************************************************
  13
  14  function: residue backend 0 implementation
  15  last mod: $Id: res0.c,v 1.14 2000/06/14 08:19:22 xiphmont Exp $
  16
  17  ********************************************************************/
  18
  19 /* Slow, slow, slow, simpleminded and did I mention it was slow?  The
  20    encode/decode loops are coded for clarity and performance is not
  21    yet even a nagging little idea lurking in the shadows.  Oh and BTW,
  22    it's slow. */
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <math.h>
  27 #include <stdio.h>
  28 #include "vorbis/codec.h"
  29 #include "bitwise.h"
  30 #include "registry.h"
  31 #include "bookinternal.h"
  32 #include "sharedbook.h"
  33 #include "misc.h"
  34 #include "os.h"
  35
  36 typedef struct {
  37   vorbis_info_residue0 *info;
  38
  39   int         parts;
  40   codebook   *phrasebook;
  41   codebook ***partbooks;
  42
  43   int         partvals;
  44   int       **decodemap;
  45 } vorbis_look_residue0;
  46
  47 void free_info(vorbis_info_residue *i){
  48   if(i){
  49     memset(i,0,sizeof(vorbis_info_residue0));
  50     free(i);
  51   }
  52 }
  53
  54 void free_look(vorbis_look_residue *i){
  55   int j;
  56   if(i){
  57     vorbis_look_residue0 *look=(vorbis_look_residue0 *)i;
  58     for(j=0;j<look->parts;j++)
  59       if(look->partbooks[j])free(look->partbooks[j]);
  60     free(look->partbooks);
  61     for(j=0;j<look->partvals;j++)
  62       free(look->decodemap[j]);
  63     free(look->decodemap);
  64     memset(i,0,sizeof(vorbis_look_residue0));
  65     free(i);
  66   }
  67 }
  68
  69 void pack(vorbis_info_residue *vr,oggpack_buffer *opb){
  70   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
  71   int j,acc=0;
  72   _oggpack_write(opb,info->begin,24);
  73   _oggpack_write(opb,info->end,24);
  74
  75   _oggpack_write(opb,info->grouping-1,24);  /* residue vectors to group and
  76                                              code with a partitioned book */
  77   _oggpack_write(opb,info->partitions-1,6); /* possible partition choices */
  78   _oggpack_write(opb,info->groupbook,8);  /* group huffman book */
  79   for(j=0;j<info->partitions;j++){
  80     _oggpack_write(opb,info->secondstages[j],4); /* zero *is* a valid choice */
  81     acc+=info->secondstages[j];
  82   }
  83   for(j=0;j<acc;j++)
  84     _oggpack_write(opb,info->booklist[j],8);
  85
  86 }
  87
  88 /* vorbis_info is for range checking */
  89 vorbis_info_residue *unpack(vorbis_info *vi,oggpack_buffer *opb){
  90   int j,acc=0;
  91   vorbis_info_residue0 *info=calloc(1,sizeof(vorbis_info_residue0));
  92
  93   info->begin=_oggpack_read(opb,24);
  94   info->end=_oggpack_read(opb,24);
  95   info->grouping=_oggpack_read(opb,24)+1;
  96   info->partitions=_oggpack_read(opb,6)+1;
  97   info->groupbook=_oggpack_read(opb,8);
  98   for(j=0;j<info->partitions;j++){
  99     acc+=info->secondstages[j]=_oggpack_read(opb,4);
 100   }
 101   for(j=0;j<acc;j++)
 102     info->booklist[j]=_oggpack_read(opb,8);
 103
 104   if(info->groupbook>=vi->books)goto errout;
 105   for(j=0;j<acc;j++)
 106     if(info->booklist[j]>=vi->books)goto errout;
 107
 108   return(info);
 109  errout:
 110   free_info(info);
 111   return(NULL);
 112 }
 113
 114 vorbis_look_residue *look (vorbis_dsp_state *vd,vorbis_info_mode *vm,
 115                           vorbis_info_residue *vr){
 116   vorbis_info_residue0 *info=(vorbis_info_residue0 *)vr;
 117   vorbis_look_residue0 *look=calloc(1,sizeof(vorbis_look_residue0));
 118   int j,k,acc=0;
 119   int dim;
 120   look->info=info;
 121
 122   look->parts=info->partitions;
 123   look->phrasebook=vd->fullbooks+info->groupbook;
 124   dim=look->phrasebook->dim;
 125
 126   look->partbooks=calloc(look->parts,sizeof(codebook **));
 127
 128   for(j=0;j<look->parts;j++){
 129     int stages=info->secondstages[j];
 130     if(stages){
 131       look->partbooks[j]=malloc(stages*sizeof(codebook *));
 132       for(k=0;k<stages;k++)
 133         look->partbooks[j][k]=vd->fullbooks+info->booklist[acc++];
 134     }
 135   }
 136
 137   look->partvals=rint(pow(look->parts,dim));
 138   look->decodemap=malloc(look->partvals*sizeof(int *));
 139   for(j=0;j<look->partvals;j++){
 140     long val=j;
 141     long mult=look->partvals/look->parts;
 142     look->decodemap[j]=malloc(dim*sizeof(int));
 143     for(k=0;k<dim;k++){
 144       long deco=val/mult;
 145       val-=deco*mult;
 146       mult/=look->parts;
 147       look->decodemap[j][k]=deco;
 148     }
 149   }
 150
 151   return(look);
 152 }
 153
 154
 155 /* does not guard against invalid settings; eg, a subn of 16 and a
 156    subgroup request of 32.  Max subn of 128 */
 157 static int _testhack(double *vec,int n,vorbis_look_residue0 *look,
 158                      int auxparts,int auxpartnum){
 159   vorbis_info_residue0 *info=look->info;
 160   int i,j=0;
 161   double max,localmax=0.;
 162   double temp[128];
 163   double entropy[8];
 164
 165   /* setup */
 166   for(i=0;i<n;i++)temp[i]=fabs(rint(vec[i]));
 167
 168   /* handle case subgrp==1 outside */
 169   for(i=0;i<n;i++)
 170     if(temp[i]>localmax)localmax=temp[i];
 171   max=localmax;
 172
 173   while(1){
 174     entropy[j]=localmax;
 175     n>>=1;
 176     j++;
 177
 178     if(n<=0)break;
 179     for(i=0;i<n;i++){
 180       temp[i]+=temp[i+n];
 181     }
 182     localmax=0.;
 183     for(i=0;i<n;i++)
 184       if(temp[i]>localmax)localmax=temp[i];
 185   }
 186
 187   for(i=0;i<auxparts-1;i++)
 188     if(auxpartnum<info->blimit[i] &&
 189        entropy[info->subgrp[i]]<=info->entmax[i] &&
 190        max<=info->ampmax[i])
 191       break;
 192
 193   return(i);
 194 }
 195
 196 static int _encodepart(oggpack_buffer *opb,double *vec, int n,
 197                        int stages, codebook **books){
 198   int i,j,bits=0;
 199
 200   for(j=0;j<stages;j++){
 201     int dim=books[j]->dim;
 202     int step=n/dim;
 203     for(i=0;i<step;i++)
 204       bits+=vorbis_book_encodevs(books[j],vec+i,opb,step,0);
 205
 206   }
 207
 208   return(bits);
 209 }
 210
 211 static int _decodepart(oggpack_buffer *opb,double *work,double *vec, int n,
 212                        int stages, codebook **books){
 213   int i,j;
 214
 215   memset(work,0,sizeof(double)*n);
 216   for(j=0;j<stages;j++){
 217     int dim=books[j]->dim;
 218     int step=n/dim;
 219     for(i=0;i<step;i++)
 220       vorbis_book_decodevs(books[j],work+i,opb,step,0);
 221   }
 222
 223   for(i=0;i<n;i++)
 224     vec[i]*=work[i];
 225
 226   return(0);
 227 }
 228
 229 int forward(vorbis_block *vb,vorbis_look_residue *vl,
 230             double **in,int ch){
 231   long i,j,k,l;
 232   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 233   vorbis_info_residue0 *info=look->info;
 234
 235   /* move all this setup out later */
 236   int samples_per_partition=info->grouping;
 237   int possible_partitions=info->partitions;
 238   int partitions_per_word=look->phrasebook->dim;
 239   int n=info->end-info->begin;
 240   long phrasebits=0,resbitsT=0;
 241   long *resbits=alloca(sizeof(long)*possible_partitions);
 242   long *resvals=alloca(sizeof(long)*possible_partitions);
 243
 244   int partvals=n/samples_per_partition;
 245   int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 246   long **partword=_vorbis_block_alloc(vb,ch*sizeof(long *));
 247
 248   partvals=partwords*partitions_per_word;
 249
 250   /* we find the patition type for each partition of each
 251      channel.  We'll go back and do the interleaved encoding in a
 252      bit.  For now, clarity */
 253
 254   memset(resbits,0,sizeof(long)*possible_partitions);
 255   memset(resvals,0,sizeof(long)*possible_partitions);
 256
 257   for(i=0;i<ch;i++){
 258     partword[i]=_vorbis_block_alloc(vb,n/samples_per_partition*sizeof(long));
 259     memset(partword[i],0,n/samples_per_partition*sizeof(long));
 260   }
 261
 262   for(i=info->begin,l=0;i<info->end;i+=samples_per_partition,l++){
 263     for(j=0;j<ch;j++)
 264       /* do the partition decision based on the number of 'bits'
 265          needed to encode the block */
 266       partword[j][l]=
 267         _testhack(in[j]+i,samples_per_partition,look,possible_partitions,l);
 268
 269   }
 270   /* we code the partition words for each channel, then the residual
 271      words for a partition per channel until we've written all the
 272      residual words for that partition word.  Then write the next
 273      parition channel words... */
 274
 275   for(i=info->begin,l=0;i<info->end;){
 276     /* first we encode a partition codeword for each channel */
 277     for(j=0;j<ch;j++){
 278       long val=partword[j][l];
 279       for(k=1;k<partitions_per_word;k++)
 280         val= val*possible_partitions+partword[j][l+k];
 281       phrasebits+=vorbis_book_encode(look->phrasebook,val,&vb->opb);
 282     }
 283     /* now we encode interleaved residual values for the partitions */
 284     for(k=0;k<partitions_per_word;k++,l++,i+=samples_per_partition)
 285       for(j=0;j<ch;j++){
 286         resbits[partword[j][l]]+=
 287           _encodepart(&vb->opb,in[j]+i,samples_per_partition,
 288                       info->secondstages[partword[j][l]],
 289                       look->partbooks[partword[j][l]]);
 290         resvals[partword[j][l]]+=samples_per_partition;
 291       }
 292
 293   }
 294
 295   for(i=0;i<possible_partitions;i++)resbitsT+=resbits[i];
 296   /*fprintf(stderr,
 297           "Encoded %ld res vectors in %ld phrasing and %ld res bits\n\t",
 298           ch*(info->end-info->begin),phrasebits,resbitsT);
 299   for(i=0;i<possible_partitions;i++)
 300     fprintf(stderr,"%ld(%ld):%ld ",i,resvals[i],resbits[i]);
 301     fprintf(stderr,"\n");*/
 302
 303   return(0);
 304 }
 305
 306 int inverse(vorbis_block *vb,vorbis_look_residue *vl,double **in,int ch){
 307   long i,j,k,l;
 308   vorbis_look_residue0 *look=(vorbis_look_residue0 *)vl;
 309   vorbis_info_residue0 *info=look->info;
 310
 311   /* move all this setup out later */
 312   int samples_per_partition=info->grouping;
 313   int partitions_per_word=look->phrasebook->dim;
 314   int n=info->end-info->begin;
 315
 316   int partvals=n/samples_per_partition;
 317   int partwords=(partvals+partitions_per_word-1)/partitions_per_word;
 318   int **partword=alloca(ch*sizeof(long *));
 319   double *work=alloca(sizeof(double)*samples_per_partition);
 320   partvals=partwords*partitions_per_word;
 321
 322   for(i=info->begin,l=0;i<info->end;){
 323     /* fetch the partition word for each channel */
 324     for(j=0;j<ch;j++){
 325       int temp=vorbis_book_decode(look->phrasebook,&vb->opb);
 326       partword[j]=look->decodemap[temp];
 327       if(partword[j]==NULL)exit(1);
 328     }
 329
 330     /* now we decode interleaved residual values for the partitions */
 331     for(k=0;k<partitions_per_word;k++,l++,i+=samples_per_partition)
 332       for(j=0;j<ch;j++){
 333         int part=partword[j][k];
 334         _decodepart(&vb->opb,work,in[j]+i,samples_per_partition,
 335                     info->secondstages[part],
 336                     look->partbooks[part]);
 337       }
 338   }
 339
 340   return(0);
 341 }
 342
 343 vorbis_func_residue residue0_exportbundle={
 344   &pack,
 345   &unpack,
 346   &look,
 347   &free_info,
 348   &free_look,
 349   &forward,
 350   &inverse
 351 };