vrshoot

diff libs/vorbis/floor1.c @ 0:b2f14e535253

initial commit
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 01 Feb 2014 19:58:19 +0200
parents
children
line diff
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libs/vorbis/floor1.c	Sat Feb 01 19:58:19 2014 +0200
     1.3 @@ -0,0 +1,1100 @@
     1.4 +/********************************************************************
     1.5 + *                                                                  *
     1.6 + * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
     1.7 + * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
     1.8 + * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
     1.9 + * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
    1.10 + *                                                                  *
    1.11 + * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
    1.12 + * by the Xiph.Org Foundation http://www.xiph.org/                  *
    1.13 + *                                                                  *
    1.14 + ********************************************************************
    1.15 +
    1.16 + function: floor backend 1 implementation
    1.17 + last mod: $Id: floor1.c 18151 2012-01-20 07:35:26Z xiphmont $
    1.18 +
    1.19 + ********************************************************************/
    1.20 +
    1.21 +#include <stdlib.h>
    1.22 +#include <string.h>
    1.23 +#include <math.h>
    1.24 +#include <ogg/ogg.h>
    1.25 +#include "vorbis/codec.h"
    1.26 +#include "codec_internal.h"
    1.27 +#include "registry.h"
    1.28 +#include "codebook.h"
    1.29 +#include "misc.h"
    1.30 +#include "scales.h"
    1.31 +
    1.32 +#include <stdio.h>
    1.33 +
    1.34 +#define floor1_rangedB 140 /* floor 1 fixed at -140dB to 0dB range */
    1.35 +
    1.36 +typedef struct lsfit_acc{
    1.37 +  int x0;
    1.38 +  int x1;
    1.39 +
    1.40 +  int xa;
    1.41 +  int ya;
    1.42 +  int x2a;
    1.43 +  int y2a;
    1.44 +  int xya;
    1.45 +  int an;
    1.46 +
    1.47 +  int xb;
    1.48 +  int yb;
    1.49 +  int x2b;
    1.50 +  int y2b;
    1.51 +  int xyb;
    1.52 +  int bn;
    1.53 +} lsfit_acc;
    1.54 +
    1.55 +/***********************************************/
    1.56 +
    1.57 +static void floor1_free_info(vorbis_info_floor *i){
    1.58 +  vorbis_info_floor1 *info=(vorbis_info_floor1 *)i;
    1.59 +  if(info){
    1.60 +    memset(info,0,sizeof(*info));
    1.61 +    _ogg_free(info);
    1.62 +  }
    1.63 +}
    1.64 +
    1.65 +static void floor1_free_look(vorbis_look_floor *i){
    1.66 +  vorbis_look_floor1 *look=(vorbis_look_floor1 *)i;
    1.67 +  if(look){
    1.68 +    /*fprintf(stderr,"floor 1 bit usage %f:%f (%f total)\n",
    1.69 +            (float)look->phrasebits/look->frames,
    1.70 +            (float)look->postbits/look->frames,
    1.71 +            (float)(look->postbits+look->phrasebits)/look->frames);*/
    1.72 +
    1.73 +    memset(look,0,sizeof(*look));
    1.74 +    _ogg_free(look);
    1.75 +  }
    1.76 +}
    1.77 +
    1.78 +static int ilog(unsigned int v){
    1.79 +  int ret=0;
    1.80 +  while(v){
    1.81 +    ret++;
    1.82 +    v>>=1;
    1.83 +  }
    1.84 +  return(ret);
    1.85 +}
    1.86 +
    1.87 +static int ilog2(unsigned int v){
    1.88 +  int ret=0;
    1.89 +  if(v)--v;
    1.90 +  while(v){
    1.91 +    ret++;
    1.92 +    v>>=1;
    1.93 +  }
    1.94 +  return(ret);
    1.95 +}
    1.96 +
    1.97 +static void floor1_pack (vorbis_info_floor *i,oggpack_buffer *opb){
    1.98 +  vorbis_info_floor1 *info=(vorbis_info_floor1 *)i;
    1.99 +  int j,k;
   1.100 +  int count=0;
   1.101 +  int rangebits;
   1.102 +  int maxposit=info->postlist[1];
   1.103 +  int maxclass=-1;
   1.104 +
   1.105 +  /* save out partitions */
   1.106 +  oggpack_write(opb,info->partitions,5); /* only 0 to 31 legal */
   1.107 +  for(j=0;j<info->partitions;j++){
   1.108 +    oggpack_write(opb,info->partitionclass[j],4); /* only 0 to 15 legal */
   1.109 +    if(maxclass<info->partitionclass[j])maxclass=info->partitionclass[j];
   1.110 +  }
   1.111 +
   1.112 +  /* save out partition classes */
   1.113 +  for(j=0;j<maxclass+1;j++){
   1.114 +    oggpack_write(opb,info->class_dim[j]-1,3); /* 1 to 8 */
   1.115 +    oggpack_write(opb,info->class_subs[j],2); /* 0 to 3 */
   1.116 +    if(info->class_subs[j])oggpack_write(opb,info->class_book[j],8);
   1.117 +    for(k=0;k<(1<<info->class_subs[j]);k++)
   1.118 +      oggpack_write(opb,info->class_subbook[j][k]+1,8);
   1.119 +  }
   1.120 +
   1.121 +  /* save out the post list */
   1.122 +  oggpack_write(opb,info->mult-1,2);     /* only 1,2,3,4 legal now */
   1.123 +  oggpack_write(opb,ilog2(maxposit),4);
   1.124 +  rangebits=ilog2(maxposit);
   1.125 +
   1.126 +  for(j=0,k=0;j<info->partitions;j++){
   1.127 +    count+=info->class_dim[info->partitionclass[j]];
   1.128 +    for(;k<count;k++)
   1.129 +      oggpack_write(opb,info->postlist[k+2],rangebits);
   1.130 +  }
   1.131 +}
   1.132 +
   1.133 +static int icomp(const void *a,const void *b){
   1.134 +  return(**(int **)a-**(int **)b);
   1.135 +}
   1.136 +
   1.137 +static vorbis_info_floor *floor1_unpack (vorbis_info *vi,oggpack_buffer *opb){
   1.138 +  codec_setup_info     *ci=vi->codec_setup;
   1.139 +  int j,k,count=0,maxclass=-1,rangebits;
   1.140 +
   1.141 +  vorbis_info_floor1 *info=_ogg_calloc(1,sizeof(*info));
   1.142 +  /* read partitions */
   1.143 +  info->partitions=oggpack_read(opb,5); /* only 0 to 31 legal */
   1.144 +  for(j=0;j<info->partitions;j++){
   1.145 +    info->partitionclass[j]=oggpack_read(opb,4); /* only 0 to 15 legal */
   1.146 +    if(info->partitionclass[j]<0)goto err_out;
   1.147 +    if(maxclass<info->partitionclass[j])maxclass=info->partitionclass[j];
   1.148 +  }
   1.149 +
   1.150 +  /* read partition classes */
   1.151 +  for(j=0;j<maxclass+1;j++){
   1.152 +    info->class_dim[j]=oggpack_read(opb,3)+1; /* 1 to 8 */
   1.153 +    info->class_subs[j]=oggpack_read(opb,2); /* 0,1,2,3 bits */
   1.154 +    if(info->class_subs[j]<0)
   1.155 +      goto err_out;
   1.156 +    if(info->class_subs[j])info->class_book[j]=oggpack_read(opb,8);
   1.157 +    if(info->class_book[j]<0 || info->class_book[j]>=ci->books)
   1.158 +      goto err_out;
   1.159 +    for(k=0;k<(1<<info->class_subs[j]);k++){
   1.160 +      info->class_subbook[j][k]=oggpack_read(opb,8)-1;
   1.161 +      if(info->class_subbook[j][k]<-1 || info->class_subbook[j][k]>=ci->books)
   1.162 +        goto err_out;
   1.163 +    }
   1.164 +  }
   1.165 +
   1.166 +  /* read the post list */
   1.167 +  info->mult=oggpack_read(opb,2)+1;     /* only 1,2,3,4 legal now */
   1.168 +  rangebits=oggpack_read(opb,4);
   1.169 +  if(rangebits<0)goto err_out;
   1.170 +
   1.171 +  for(j=0,k=0;j<info->partitions;j++){
   1.172 +    count+=info->class_dim[info->partitionclass[j]];
   1.173 +    if(count>VIF_POSIT) goto err_out;
   1.174 +    for(;k<count;k++){
   1.175 +      int t=info->postlist[k+2]=oggpack_read(opb,rangebits);
   1.176 +      if(t<0 || t>=(1<<rangebits))
   1.177 +        goto err_out;
   1.178 +    }
   1.179 +  }
   1.180 +  info->postlist[0]=0;
   1.181 +  info->postlist[1]=1<<rangebits;
   1.182 +
   1.183 +  /* don't allow repeated values in post list as they'd result in
   1.184 +     zero-length segments */
   1.185 +  {
   1.186 +    int *sortpointer[VIF_POSIT+2];
   1.187 +    for(j=0;j<count+2;j++)sortpointer[j]=info->postlist+j;
   1.188 +    qsort(sortpointer,count+2,sizeof(*sortpointer),icomp);
   1.189 +
   1.190 +    for(j=1;j<count+2;j++)
   1.191 +      if(*sortpointer[j-1]==*sortpointer[j])goto err_out;
   1.192 +  }
   1.193 +
   1.194 +  return(info);
   1.195 +
   1.196 + err_out:
   1.197 +  floor1_free_info(info);
   1.198 +  return(NULL);
   1.199 +}
   1.200 +
   1.201 +static vorbis_look_floor *floor1_look(vorbis_dsp_state *vd,
   1.202 +                                      vorbis_info_floor *in){
   1.203 +
   1.204 +  int *sortpointer[VIF_POSIT+2];
   1.205 +  vorbis_info_floor1 *info=(vorbis_info_floor1 *)in;
   1.206 +  vorbis_look_floor1 *look=_ogg_calloc(1,sizeof(*look));
   1.207 +  int i,j,n=0;
   1.208 +
   1.209 +  look->vi=info;
   1.210 +  look->n=info->postlist[1];
   1.211 +
   1.212 +  /* we drop each position value in-between already decoded values,
   1.213 +     and use linear interpolation to predict each new value past the
   1.214 +     edges.  The positions are read in the order of the position
   1.215 +     list... we precompute the bounding positions in the lookup.  Of
   1.216 +     course, the neighbors can change (if a position is declined), but
   1.217 +     this is an initial mapping */
   1.218 +
   1.219 +  for(i=0;i<info->partitions;i++)n+=info->class_dim[info->partitionclass[i]];
   1.220 +  n+=2;
   1.221 +  look->posts=n;
   1.222 +
   1.223 +  /* also store a sorted position index */
   1.224 +  for(i=0;i<n;i++)sortpointer[i]=info->postlist+i;
   1.225 +  qsort(sortpointer,n,sizeof(*sortpointer),icomp);
   1.226 +
   1.227 +  /* points from sort order back to range number */
   1.228 +  for(i=0;i<n;i++)look->forward_index[i]=sortpointer[i]-info->postlist;
   1.229 +  /* points from range order to sorted position */
   1.230 +  for(i=0;i<n;i++)look->reverse_index[look->forward_index[i]]=i;
   1.231 +  /* we actually need the post values too */
   1.232 +  for(i=0;i<n;i++)look->sorted_index[i]=info->postlist[look->forward_index[i]];
   1.233 +
   1.234 +  /* quantize values to multiplier spec */
   1.235 +  switch(info->mult){
   1.236 +  case 1: /* 1024 -> 256 */
   1.237 +    look->quant_q=256;
   1.238 +    break;
   1.239 +  case 2: /* 1024 -> 128 */
   1.240 +    look->quant_q=128;
   1.241 +    break;
   1.242 +  case 3: /* 1024 -> 86 */
   1.243 +    look->quant_q=86;
   1.244 +    break;
   1.245 +  case 4: /* 1024 -> 64 */
   1.246 +    look->quant_q=64;
   1.247 +    break;
   1.248 +  }
   1.249 +
   1.250 +  /* discover our neighbors for decode where we don't use fit flags
   1.251 +     (that would push the neighbors outward) */
   1.252 +  for(i=0;i<n-2;i++){
   1.253 +    int lo=0;
   1.254 +    int hi=1;
   1.255 +    int lx=0;
   1.256 +    int hx=look->n;
   1.257 +    int currentx=info->postlist[i+2];
   1.258 +    for(j=0;j<i+2;j++){
   1.259 +      int x=info->postlist[j];
   1.260 +      if(x>lx && x<currentx){
   1.261 +        lo=j;
   1.262 +        lx=x;
   1.263 +      }
   1.264 +      if(x<hx && x>currentx){
   1.265 +        hi=j;
   1.266 +        hx=x;
   1.267 +      }
   1.268 +    }
   1.269 +    look->loneighbor[i]=lo;
   1.270 +    look->hineighbor[i]=hi;
   1.271 +  }
   1.272 +
   1.273 +  return(look);
   1.274 +}
   1.275 +
   1.276 +static int render_point(int x0,int x1,int y0,int y1,int x){
   1.277 +  y0&=0x7fff; /* mask off flag */
   1.278 +  y1&=0x7fff;
   1.279 +
   1.280 +  {
   1.281 +    int dy=y1-y0;
   1.282 +    int adx=x1-x0;
   1.283 +    int ady=abs(dy);
   1.284 +    int err=ady*(x-x0);
   1.285 +
   1.286 +    int off=err/adx;
   1.287 +    if(dy<0)return(y0-off);
   1.288 +    return(y0+off);
   1.289 +  }
   1.290 +}
   1.291 +
   1.292 +static int vorbis_dBquant(const float *x){
   1.293 +  int i= *x*7.3142857f+1023.5f;
   1.294 +  if(i>1023)return(1023);
   1.295 +  if(i<0)return(0);
   1.296 +  return i;
   1.297 +}
   1.298 +
   1.299 +static const float FLOOR1_fromdB_LOOKUP[256]={
   1.300 +  1.0649863e-07F, 1.1341951e-07F, 1.2079015e-07F, 1.2863978e-07F,
   1.301 +  1.3699951e-07F, 1.4590251e-07F, 1.5538408e-07F, 1.6548181e-07F,
   1.302 +  1.7623575e-07F, 1.8768855e-07F, 1.9988561e-07F, 2.128753e-07F,
   1.303 +  2.2670913e-07F, 2.4144197e-07F, 2.5713223e-07F, 2.7384213e-07F,
   1.304 +  2.9163793e-07F, 3.1059021e-07F, 3.3077411e-07F, 3.5226968e-07F,
   1.305 +  3.7516214e-07F, 3.9954229e-07F, 4.2550680e-07F, 4.5315863e-07F,
   1.306 +  4.8260743e-07F, 5.1396998e-07F, 5.4737065e-07F, 5.8294187e-07F,
   1.307 +  6.2082472e-07F, 6.6116941e-07F, 7.0413592e-07F, 7.4989464e-07F,
   1.308 +  7.9862701e-07F, 8.5052630e-07F, 9.0579828e-07F, 9.6466216e-07F,
   1.309 +  1.0273513e-06F, 1.0941144e-06F, 1.1652161e-06F, 1.2409384e-06F,
   1.310 +  1.3215816e-06F, 1.4074654e-06F, 1.4989305e-06F, 1.5963394e-06F,
   1.311 +  1.7000785e-06F, 1.8105592e-06F, 1.9282195e-06F, 2.0535261e-06F,
   1.312 +  2.1869758e-06F, 2.3290978e-06F, 2.4804557e-06F, 2.6416497e-06F,
   1.313 +  2.8133190e-06F, 2.9961443e-06F, 3.1908506e-06F, 3.3982101e-06F,
   1.314 +  3.6190449e-06F, 3.8542308e-06F, 4.1047004e-06F, 4.3714470e-06F,
   1.315 +  4.6555282e-06F, 4.9580707e-06F, 5.2802740e-06F, 5.6234160e-06F,
   1.316 +  5.9888572e-06F, 6.3780469e-06F, 6.7925283e-06F, 7.2339451e-06F,
   1.317 +  7.7040476e-06F, 8.2047000e-06F, 8.7378876e-06F, 9.3057248e-06F,
   1.318 +  9.9104632e-06F, 1.0554501e-05F, 1.1240392e-05F, 1.1970856e-05F,
   1.319 +  1.2748789e-05F, 1.3577278e-05F, 1.4459606e-05F, 1.5399272e-05F,
   1.320 +  1.6400004e-05F, 1.7465768e-05F, 1.8600792e-05F, 1.9809576e-05F,
   1.321 +  2.1096914e-05F, 2.2467911e-05F, 2.3928002e-05F, 2.5482978e-05F,
   1.322 +  2.7139006e-05F, 2.8902651e-05F, 3.0780908e-05F, 3.2781225e-05F,
   1.323 +  3.4911534e-05F, 3.7180282e-05F, 3.9596466e-05F, 4.2169667e-05F,
   1.324 +  4.4910090e-05F, 4.7828601e-05F, 5.0936773e-05F, 5.4246931e-05F,
   1.325 +  5.7772202e-05F, 6.1526565e-05F, 6.5524908e-05F, 6.9783085e-05F,
   1.326 +  7.4317983e-05F, 7.9147585e-05F, 8.4291040e-05F, 8.9768747e-05F,
   1.327 +  9.5602426e-05F, 0.00010181521F, 0.00010843174F, 0.00011547824F,
   1.328 +  0.00012298267F, 0.00013097477F, 0.00013948625F, 0.00014855085F,
   1.329 +  0.00015820453F, 0.00016848555F, 0.00017943469F, 0.00019109536F,
   1.330 +  0.00020351382F, 0.00021673929F, 0.00023082423F, 0.00024582449F,
   1.331 +  0.00026179955F, 0.00027881276F, 0.00029693158F, 0.00031622787F,
   1.332 +  0.00033677814F, 0.00035866388F, 0.00038197188F, 0.00040679456F,
   1.333 +  0.00043323036F, 0.00046138411F, 0.00049136745F, 0.00052329927F,
   1.334 +  0.00055730621F, 0.00059352311F, 0.00063209358F, 0.00067317058F,
   1.335 +  0.00071691700F, 0.00076350630F, 0.00081312324F, 0.00086596457F,
   1.336 +  0.00092223983F, 0.00098217216F, 0.0010459992F, 0.0011139742F,
   1.337 +  0.0011863665F, 0.0012634633F, 0.0013455702F, 0.0014330129F,
   1.338 +  0.0015261382F, 0.0016253153F, 0.0017309374F, 0.0018434235F,
   1.339 +  0.0019632195F, 0.0020908006F, 0.0022266726F, 0.0023713743F,
   1.340 +  0.0025254795F, 0.0026895994F, 0.0028643847F, 0.0030505286F,
   1.341 +  0.0032487691F, 0.0034598925F, 0.0036847358F, 0.0039241906F,
   1.342 +  0.0041792066F, 0.0044507950F, 0.0047400328F, 0.0050480668F,
   1.343 +  0.0053761186F, 0.0057254891F, 0.0060975636F, 0.0064938176F,
   1.344 +  0.0069158225F, 0.0073652516F, 0.0078438871F, 0.0083536271F,
   1.345 +  0.0088964928F, 0.009474637F, 0.010090352F, 0.010746080F,
   1.346 +  0.011444421F, 0.012188144F, 0.012980198F, 0.013823725F,
   1.347 +  0.014722068F, 0.015678791F, 0.016697687F, 0.017782797F,
   1.348 +  0.018938423F, 0.020169149F, 0.021479854F, 0.022875735F,
   1.349 +  0.024362330F, 0.025945531F, 0.027631618F, 0.029427276F,
   1.350 +  0.031339626F, 0.033376252F, 0.035545228F, 0.037855157F,
   1.351 +  0.040315199F, 0.042935108F, 0.045725273F, 0.048696758F,
   1.352 +  0.051861348F, 0.055231591F, 0.058820850F, 0.062643361F,
   1.353 +  0.066714279F, 0.071049749F, 0.075666962F, 0.080584227F,
   1.354 +  0.085821044F, 0.091398179F, 0.097337747F, 0.10366330F,
   1.355 +  0.11039993F, 0.11757434F, 0.12521498F, 0.13335215F,
   1.356 +  0.14201813F, 0.15124727F, 0.16107617F, 0.17154380F,
   1.357 +  0.18269168F, 0.19456402F, 0.20720788F, 0.22067342F,
   1.358 +  0.23501402F, 0.25028656F, 0.26655159F, 0.28387361F,
   1.359 +  0.30232132F, 0.32196786F, 0.34289114F, 0.36517414F,
   1.360 +  0.38890521F, 0.41417847F, 0.44109412F, 0.46975890F,
   1.361 +  0.50028648F, 0.53279791F, 0.56742212F, 0.60429640F,
   1.362 +  0.64356699F, 0.68538959F, 0.72993007F, 0.77736504F,
   1.363 +  0.82788260F, 0.88168307F, 0.9389798F, 1.F,
   1.364 +};
   1.365 +
   1.366 +static void render_line(int n, int x0,int x1,int y0,int y1,float *d){
   1.367 +  int dy=y1-y0;
   1.368 +  int adx=x1-x0;
   1.369 +  int ady=abs(dy);
   1.370 +  int base=dy/adx;
   1.371 +  int sy=(dy<0?base-1:base+1);
   1.372 +  int x=x0;
   1.373 +  int y=y0;
   1.374 +  int err=0;
   1.375 +
   1.376 +  ady-=abs(base*adx);
   1.377 +
   1.378 +  if(n>x1)n=x1;
   1.379 +
   1.380 +  if(x<n)
   1.381 +    d[x]*=FLOOR1_fromdB_LOOKUP[y];
   1.382 +
   1.383 +  while(++x<n){
   1.384 +    err=err+ady;
   1.385 +    if(err>=adx){
   1.386 +      err-=adx;
   1.387 +      y+=sy;
   1.388 +    }else{
   1.389 +      y+=base;
   1.390 +    }
   1.391 +    d[x]*=FLOOR1_fromdB_LOOKUP[y];
   1.392 +  }
   1.393 +}
   1.394 +
   1.395 +static void render_line0(int n, int x0,int x1,int y0,int y1,int *d){
   1.396 +  int dy=y1-y0;
   1.397 +  int adx=x1-x0;
   1.398 +  int ady=abs(dy);
   1.399 +  int base=dy/adx;
   1.400 +  int sy=(dy<0?base-1:base+1);
   1.401 +  int x=x0;
   1.402 +  int y=y0;
   1.403 +  int err=0;
   1.404 +
   1.405 +  ady-=abs(base*adx);
   1.406 +
   1.407 +  if(n>x1)n=x1;
   1.408 +
   1.409 +  if(x<n)
   1.410 +    d[x]=y;
   1.411 +
   1.412 +  while(++x<n){
   1.413 +    err=err+ady;
   1.414 +    if(err>=adx){
   1.415 +      err-=adx;
   1.416 +      y+=sy;
   1.417 +    }else{
   1.418 +      y+=base;
   1.419 +    }
   1.420 +    d[x]=y;
   1.421 +  }
   1.422 +}
   1.423 +
   1.424 +/* the floor has already been filtered to only include relevant sections */
   1.425 +static int accumulate_fit(const float *flr,const float *mdct,
   1.426 +                          int x0, int x1,lsfit_acc *a,
   1.427 +                          int n,vorbis_info_floor1 *info){
   1.428 +  long i;
   1.429 +
   1.430 +  int xa=0,ya=0,x2a=0,y2a=0,xya=0,na=0, xb=0,yb=0,x2b=0,y2b=0,xyb=0,nb=0;
   1.431 +
   1.432 +  memset(a,0,sizeof(*a));
   1.433 +  a->x0=x0;
   1.434 +  a->x1=x1;
   1.435 +  if(x1>=n)x1=n-1;
   1.436 +
   1.437 +  for(i=x0;i<=x1;i++){
   1.438 +    int quantized=vorbis_dBquant(flr+i);
   1.439 +    if(quantized){
   1.440 +      if(mdct[i]+info->twofitatten>=flr[i]){
   1.441 +        xa  += i;
   1.442 +        ya  += quantized;
   1.443 +        x2a += i*i;
   1.444 +        y2a += quantized*quantized;
   1.445 +        xya += i*quantized;
   1.446 +        na++;
   1.447 +      }else{
   1.448 +        xb  += i;
   1.449 +        yb  += quantized;
   1.450 +        x2b += i*i;
   1.451 +        y2b += quantized*quantized;
   1.452 +        xyb += i*quantized;
   1.453 +        nb++;
   1.454 +      }
   1.455 +    }
   1.456 +  }
   1.457 +
   1.458 +  a->xa=xa;
   1.459 +  a->ya=ya;
   1.460 +  a->x2a=x2a;
   1.461 +  a->y2a=y2a;
   1.462 +  a->xya=xya;
   1.463 +  a->an=na;
   1.464 +
   1.465 +  a->xb=xb;
   1.466 +  a->yb=yb;
   1.467 +  a->x2b=x2b;
   1.468 +  a->y2b=y2b;
   1.469 +  a->xyb=xyb;
   1.470 +  a->bn=nb;
   1.471 +
   1.472 +  return(na);
   1.473 +}
   1.474 +
   1.475 +static int fit_line(lsfit_acc *a,int fits,int *y0,int *y1,
   1.476 +                    vorbis_info_floor1 *info){
   1.477 +  double xb=0,yb=0,x2b=0,y2b=0,xyb=0,bn=0;
   1.478 +  int i;
   1.479 +  int x0=a[0].x0;
   1.480 +  int x1=a[fits-1].x1;
   1.481 +
   1.482 +  for(i=0;i<fits;i++){
   1.483 +    double weight = (a[i].bn+a[i].an)*info->twofitweight/(a[i].an+1)+1.;
   1.484 +
   1.485 +    xb+=a[i].xb + a[i].xa * weight;
   1.486 +    yb+=a[i].yb + a[i].ya * weight;
   1.487 +    x2b+=a[i].x2b + a[i].x2a * weight;
   1.488 +    y2b+=a[i].y2b + a[i].y2a * weight;
   1.489 +    xyb+=a[i].xyb + a[i].xya * weight;
   1.490 +    bn+=a[i].bn + a[i].an * weight;
   1.491 +  }
   1.492 +
   1.493 +  if(*y0>=0){
   1.494 +    xb+=   x0;
   1.495 +    yb+=  *y0;
   1.496 +    x2b+=  x0 *  x0;
   1.497 +    y2b+= *y0 * *y0;
   1.498 +    xyb+= *y0 *  x0;
   1.499 +    bn++;
   1.500 +  }
   1.501 +
   1.502 +  if(*y1>=0){
   1.503 +    xb+=   x1;
   1.504 +    yb+=  *y1;
   1.505 +    x2b+=  x1 *  x1;
   1.506 +    y2b+= *y1 * *y1;
   1.507 +    xyb+= *y1 *  x1;
   1.508 +    bn++;
   1.509 +  }
   1.510 +
   1.511 +  {
   1.512 +    double denom=(bn*x2b-xb*xb);
   1.513 +
   1.514 +    if(denom>0.){
   1.515 +      double a=(yb*x2b-xyb*xb)/denom;
   1.516 +      double b=(bn*xyb-xb*yb)/denom;
   1.517 +      *y0=rint(a+b*x0);
   1.518 +      *y1=rint(a+b*x1);
   1.519 +
   1.520 +      /* limit to our range! */
   1.521 +      if(*y0>1023)*y0=1023;
   1.522 +      if(*y1>1023)*y1=1023;
   1.523 +      if(*y0<0)*y0=0;
   1.524 +      if(*y1<0)*y1=0;
   1.525 +
   1.526 +      return 0;
   1.527 +    }else{
   1.528 +      *y0=0;
   1.529 +      *y1=0;
   1.530 +      return 1;
   1.531 +    }
   1.532 +  }
   1.533 +}
   1.534 +
   1.535 +static int inspect_error(int x0,int x1,int y0,int y1,const float *mask,
   1.536 +                         const float *mdct,
   1.537 +                         vorbis_info_floor1 *info){
   1.538 +  int dy=y1-y0;
   1.539 +  int adx=x1-x0;
   1.540 +  int ady=abs(dy);
   1.541 +  int base=dy/adx;
   1.542 +  int sy=(dy<0?base-1:base+1);
   1.543 +  int x=x0;
   1.544 +  int y=y0;
   1.545 +  int err=0;
   1.546 +  int val=vorbis_dBquant(mask+x);
   1.547 +  int mse=0;
   1.548 +  int n=0;
   1.549 +
   1.550 +  ady-=abs(base*adx);
   1.551 +
   1.552 +  mse=(y-val);
   1.553 +  mse*=mse;
   1.554 +  n++;
   1.555 +  if(mdct[x]+info->twofitatten>=mask[x]){
   1.556 +    if(y+info->maxover<val)return(1);
   1.557 +    if(y-info->maxunder>val)return(1);
   1.558 +  }
   1.559 +
   1.560 +  while(++x<x1){
   1.561 +    err=err+ady;
   1.562 +    if(err>=adx){
   1.563 +      err-=adx;
   1.564 +      y+=sy;
   1.565 +    }else{
   1.566 +      y+=base;
   1.567 +    }
   1.568 +
   1.569 +    val=vorbis_dBquant(mask+x);
   1.570 +    mse+=((y-val)*(y-val));
   1.571 +    n++;
   1.572 +    if(mdct[x]+info->twofitatten>=mask[x]){
   1.573 +      if(val){
   1.574 +        if(y+info->maxover<val)return(1);
   1.575 +        if(y-info->maxunder>val)return(1);
   1.576 +      }
   1.577 +    }
   1.578 +  }
   1.579 +
   1.580 +  if(info->maxover*info->maxover/n>info->maxerr)return(0);
   1.581 +  if(info->maxunder*info->maxunder/n>info->maxerr)return(0);
   1.582 +  if(mse/n>info->maxerr)return(1);
   1.583 +  return(0);
   1.584 +}
   1.585 +
   1.586 +static int post_Y(int *A,int *B,int pos){
   1.587 +  if(A[pos]<0)
   1.588 +    return B[pos];
   1.589 +  if(B[pos]<0)
   1.590 +    return A[pos];
   1.591 +
   1.592 +  return (A[pos]+B[pos])>>1;
   1.593 +}
   1.594 +
   1.595 +int *floor1_fit(vorbis_block *vb,vorbis_look_floor1 *look,
   1.596 +                          const float *logmdct,   /* in */
   1.597 +                          const float *logmask){
   1.598 +  long i,j;
   1.599 +  vorbis_info_floor1 *info=look->vi;
   1.600 +  long n=look->n;
   1.601 +  long posts=look->posts;
   1.602 +  long nonzero=0;
   1.603 +  lsfit_acc fits[VIF_POSIT+1];
   1.604 +  int fit_valueA[VIF_POSIT+2]; /* index by range list position */
   1.605 +  int fit_valueB[VIF_POSIT+2]; /* index by range list position */
   1.606 +
   1.607 +  int loneighbor[VIF_POSIT+2]; /* sorted index of range list position (+2) */
   1.608 +  int hineighbor[VIF_POSIT+2];
   1.609 +  int *output=NULL;
   1.610 +  int memo[VIF_POSIT+2];
   1.611 +
   1.612 +  for(i=0;i<posts;i++)fit_valueA[i]=-200; /* mark all unused */
   1.613 +  for(i=0;i<posts;i++)fit_valueB[i]=-200; /* mark all unused */
   1.614 +  for(i=0;i<posts;i++)loneighbor[i]=0; /* 0 for the implicit 0 post */
   1.615 +  for(i=0;i<posts;i++)hineighbor[i]=1; /* 1 for the implicit post at n */
   1.616 +  for(i=0;i<posts;i++)memo[i]=-1;      /* no neighbor yet */
   1.617 +
   1.618 +  /* quantize the relevant floor points and collect them into line fit
   1.619 +     structures (one per minimal division) at the same time */
   1.620 +  if(posts==0){
   1.621 +    nonzero+=accumulate_fit(logmask,logmdct,0,n,fits,n,info);
   1.622 +  }else{
   1.623 +    for(i=0;i<posts-1;i++)
   1.624 +      nonzero+=accumulate_fit(logmask,logmdct,look->sorted_index[i],
   1.625 +                              look->sorted_index[i+1],fits+i,
   1.626 +                              n,info);
   1.627 +  }
   1.628 +
   1.629 +  if(nonzero){
   1.630 +    /* start by fitting the implicit base case.... */
   1.631 +    int y0=-200;
   1.632 +    int y1=-200;
   1.633 +    fit_line(fits,posts-1,&y0,&y1,info);
   1.634 +
   1.635 +    fit_valueA[0]=y0;
   1.636 +    fit_valueB[0]=y0;
   1.637 +    fit_valueB[1]=y1;
   1.638 +    fit_valueA[1]=y1;
   1.639 +
   1.640 +    /* Non degenerate case */
   1.641 +    /* start progressive splitting.  This is a greedy, non-optimal
   1.642 +       algorithm, but simple and close enough to the best
   1.643 +       answer. */
   1.644 +    for(i=2;i<posts;i++){
   1.645 +      int sortpos=look->reverse_index[i];
   1.646 +      int ln=loneighbor[sortpos];
   1.647 +      int hn=hineighbor[sortpos];
   1.648 +
   1.649 +      /* eliminate repeat searches of a particular range with a memo */
   1.650 +      if(memo[ln]!=hn){
   1.651 +        /* haven't performed this error search yet */
   1.652 +        int lsortpos=look->reverse_index[ln];
   1.653 +        int hsortpos=look->reverse_index[hn];
   1.654 +        memo[ln]=hn;
   1.655 +
   1.656 +        {
   1.657 +          /* A note: we want to bound/minimize *local*, not global, error */
   1.658 +          int lx=info->postlist[ln];
   1.659 +          int hx=info->postlist[hn];
   1.660 +          int ly=post_Y(fit_valueA,fit_valueB,ln);
   1.661 +          int hy=post_Y(fit_valueA,fit_valueB,hn);
   1.662 +
   1.663 +          if(ly==-1 || hy==-1){
   1.664 +            exit(1);
   1.665 +          }
   1.666 +
   1.667 +          if(inspect_error(lx,hx,ly,hy,logmask,logmdct,info)){
   1.668 +            /* outside error bounds/begin search area.  Split it. */
   1.669 +            int ly0=-200;
   1.670 +            int ly1=-200;
   1.671 +            int hy0=-200;
   1.672 +            int hy1=-200;
   1.673 +            int ret0=fit_line(fits+lsortpos,sortpos-lsortpos,&ly0,&ly1,info);
   1.674 +            int ret1=fit_line(fits+sortpos,hsortpos-sortpos,&hy0,&hy1,info);
   1.675 +
   1.676 +            if(ret0){
   1.677 +              ly0=ly;
   1.678 +              ly1=hy0;
   1.679 +            }
   1.680 +            if(ret1){
   1.681 +              hy0=ly1;
   1.682 +              hy1=hy;
   1.683 +            }
   1.684 +
   1.685 +            if(ret0 && ret1){
   1.686 +              fit_valueA[i]=-200;
   1.687 +              fit_valueB[i]=-200;
   1.688 +            }else{
   1.689 +              /* store new edge values */
   1.690 +              fit_valueB[ln]=ly0;
   1.691 +              if(ln==0)fit_valueA[ln]=ly0;
   1.692 +              fit_valueA[i]=ly1;
   1.693 +              fit_valueB[i]=hy0;
   1.694 +              fit_valueA[hn]=hy1;
   1.695 +              if(hn==1)fit_valueB[hn]=hy1;
   1.696 +
   1.697 +              if(ly1>=0 || hy0>=0){
   1.698 +                /* store new neighbor values */
   1.699 +                for(j=sortpos-1;j>=0;j--)
   1.700 +                  if(hineighbor[j]==hn)
   1.701 +                    hineighbor[j]=i;
   1.702 +                  else
   1.703 +                    break;
   1.704 +                for(j=sortpos+1;j<posts;j++)
   1.705 +                  if(loneighbor[j]==ln)
   1.706 +                    loneighbor[j]=i;
   1.707 +                  else
   1.708 +                    break;
   1.709 +              }
   1.710 +            }
   1.711 +          }else{
   1.712 +            fit_valueA[i]=-200;
   1.713 +            fit_valueB[i]=-200;
   1.714 +          }
   1.715 +        }
   1.716 +      }
   1.717 +    }
   1.718 +
   1.719 +    output=_vorbis_block_alloc(vb,sizeof(*output)*posts);
   1.720 +
   1.721 +    output[0]=post_Y(fit_valueA,fit_valueB,0);
   1.722 +    output[1]=post_Y(fit_valueA,fit_valueB,1);
   1.723 +
   1.724 +    /* fill in posts marked as not using a fit; we will zero
   1.725 +       back out to 'unused' when encoding them so long as curve
   1.726 +       interpolation doesn't force them into use */
   1.727 +    for(i=2;i<posts;i++){
   1.728 +      int ln=look->loneighbor[i-2];
   1.729 +      int hn=look->hineighbor[i-2];
   1.730 +      int x0=info->postlist[ln];
   1.731 +      int x1=info->postlist[hn];
   1.732 +      int y0=output[ln];
   1.733 +      int y1=output[hn];
   1.734 +
   1.735 +      int predicted=render_point(x0,x1,y0,y1,info->postlist[i]);
   1.736 +      int vx=post_Y(fit_valueA,fit_valueB,i);
   1.737 +
   1.738 +      if(vx>=0 && predicted!=vx){
   1.739 +        output[i]=vx;
   1.740 +      }else{
   1.741 +        output[i]= predicted|0x8000;
   1.742 +      }
   1.743 +    }
   1.744 +  }
   1.745 +
   1.746 +  return(output);
   1.747 +
   1.748 +}
   1.749 +
   1.750 +int *floor1_interpolate_fit(vorbis_block *vb,vorbis_look_floor1 *look,
   1.751 +                          int *A,int *B,
   1.752 +                          int del){
   1.753 +
   1.754 +  long i;
   1.755 +  long posts=look->posts;
   1.756 +  int *output=NULL;
   1.757 +
   1.758 +  if(A && B){
   1.759 +    output=_vorbis_block_alloc(vb,sizeof(*output)*posts);
   1.760 +
   1.761 +    /* overly simpleminded--- look again post 1.2 */
   1.762 +    for(i=0;i<posts;i++){
   1.763 +      output[i]=((65536-del)*(A[i]&0x7fff)+del*(B[i]&0x7fff)+32768)>>16;
   1.764 +      if(A[i]&0x8000 && B[i]&0x8000)output[i]|=0x8000;
   1.765 +    }
   1.766 +  }
   1.767 +
   1.768 +  return(output);
   1.769 +}
   1.770 +
   1.771 +
   1.772 +int floor1_encode(oggpack_buffer *opb,vorbis_block *vb,
   1.773 +                  vorbis_look_floor1 *look,
   1.774 +                  int *post,int *ilogmask){
   1.775 +
   1.776 +  long i,j;
   1.777 +  vorbis_info_floor1 *info=look->vi;
   1.778 +  long posts=look->posts;
   1.779 +  codec_setup_info *ci=vb->vd->vi->codec_setup;
   1.780 +  int out[VIF_POSIT+2];
   1.781 +  static_codebook **sbooks=ci->book_param;
   1.782 +  codebook *books=ci->fullbooks;
   1.783 +
   1.784 +  /* quantize values to multiplier spec */
   1.785 +  if(post){
   1.786 +    for(i=0;i<posts;i++){
   1.787 +      int val=post[i]&0x7fff;
   1.788 +      switch(info->mult){
   1.789 +      case 1: /* 1024 -> 256 */
   1.790 +        val>>=2;
   1.791 +        break;
   1.792 +      case 2: /* 1024 -> 128 */
   1.793 +        val>>=3;
   1.794 +        break;
   1.795 +      case 3: /* 1024 -> 86 */
   1.796 +        val/=12;
   1.797 +        break;
   1.798 +      case 4: /* 1024 -> 64 */
   1.799 +        val>>=4;
   1.800 +        break;
   1.801 +      }
   1.802 +      post[i]=val | (post[i]&0x8000);
   1.803 +    }
   1.804 +
   1.805 +    out[0]=post[0];
   1.806 +    out[1]=post[1];
   1.807 +
   1.808 +    /* find prediction values for each post and subtract them */
   1.809 +    for(i=2;i<posts;i++){
   1.810 +      int ln=look->loneighbor[i-2];
   1.811 +      int hn=look->hineighbor[i-2];
   1.812 +      int x0=info->postlist[ln];
   1.813 +      int x1=info->postlist[hn];
   1.814 +      int y0=post[ln];
   1.815 +      int y1=post[hn];
   1.816 +
   1.817 +      int predicted=render_point(x0,x1,y0,y1,info->postlist[i]);
   1.818 +
   1.819 +      if((post[i]&0x8000) || (predicted==post[i])){
   1.820 +        post[i]=predicted|0x8000; /* in case there was roundoff jitter
   1.821 +                                     in interpolation */
   1.822 +        out[i]=0;
   1.823 +      }else{
   1.824 +        int headroom=(look->quant_q-predicted<predicted?
   1.825 +                      look->quant_q-predicted:predicted);
   1.826 +
   1.827 +        int val=post[i]-predicted;
   1.828 +
   1.829 +        /* at this point the 'deviation' value is in the range +/- max
   1.830 +           range, but the real, unique range can always be mapped to
   1.831 +           only [0-maxrange).  So we want to wrap the deviation into
   1.832 +           this limited range, but do it in the way that least screws
   1.833 +           an essentially gaussian probability distribution. */
   1.834 +
   1.835 +        if(val<0)
   1.836 +          if(val<-headroom)
   1.837 +            val=headroom-val-1;
   1.838 +          else
   1.839 +            val=-1-(val<<1);
   1.840 +        else
   1.841 +          if(val>=headroom)
   1.842 +            val= val+headroom;
   1.843 +          else
   1.844 +            val<<=1;
   1.845 +
   1.846 +        out[i]=val;
   1.847 +        post[ln]&=0x7fff;
   1.848 +        post[hn]&=0x7fff;
   1.849 +      }
   1.850 +    }
   1.851 +
   1.852 +    /* we have everything we need. pack it out */
   1.853 +    /* mark nontrivial floor */
   1.854 +    oggpack_write(opb,1,1);
   1.855 +
   1.856 +    /* beginning/end post */
   1.857 +    look->frames++;
   1.858 +    look->postbits+=ilog(look->quant_q-1)*2;
   1.859 +    oggpack_write(opb,out[0],ilog(look->quant_q-1));
   1.860 +    oggpack_write(opb,out[1],ilog(look->quant_q-1));
   1.861 +
   1.862 +
   1.863 +    /* partition by partition */
   1.864 +    for(i=0,j=2;i<info->partitions;i++){
   1.865 +      int class=info->partitionclass[i];
   1.866 +      int cdim=info->class_dim[class];
   1.867 +      int csubbits=info->class_subs[class];
   1.868 +      int csub=1<<csubbits;
   1.869 +      int bookas[8]={0,0,0,0,0,0,0,0};
   1.870 +      int cval=0;
   1.871 +      int cshift=0;
   1.872 +      int k,l;
   1.873 +
   1.874 +      /* generate the partition's first stage cascade value */
   1.875 +      if(csubbits){
   1.876 +        int maxval[8];
   1.877 +        for(k=0;k<csub;k++){
   1.878 +          int booknum=info->class_subbook[class][k];
   1.879 +          if(booknum<0){
   1.880 +            maxval[k]=1;
   1.881 +          }else{
   1.882 +            maxval[k]=sbooks[info->class_subbook[class][k]]->entries;
   1.883 +          }
   1.884 +        }
   1.885 +        for(k=0;k<cdim;k++){
   1.886 +          for(l=0;l<csub;l++){
   1.887 +            int val=out[j+k];
   1.888 +            if(val<maxval[l]){
   1.889 +              bookas[k]=l;
   1.890 +              break;
   1.891 +            }
   1.892 +          }
   1.893 +          cval|= bookas[k]<<cshift;
   1.894 +          cshift+=csubbits;
   1.895 +        }
   1.896 +        /* write it */
   1.897 +        look->phrasebits+=
   1.898 +          vorbis_book_encode(books+info->class_book[class],cval,opb);
   1.899 +
   1.900 +#ifdef TRAIN_FLOOR1
   1.901 +        {
   1.902 +          FILE *of;
   1.903 +          char buffer[80];
   1.904 +          sprintf(buffer,"line_%dx%ld_class%d.vqd",
   1.905 +                  vb->pcmend/2,posts-2,class);
   1.906 +          of=fopen(buffer,"a");
   1.907 +          fprintf(of,"%d\n",cval);
   1.908 +          fclose(of);
   1.909 +        }
   1.910 +#endif
   1.911 +      }
   1.912 +
   1.913 +      /* write post values */
   1.914 +      for(k=0;k<cdim;k++){
   1.915 +        int book=info->class_subbook[class][bookas[k]];
   1.916 +        if(book>=0){
   1.917 +          /* hack to allow training with 'bad' books */
   1.918 +          if(out[j+k]<(books+book)->entries)
   1.919 +            look->postbits+=vorbis_book_encode(books+book,
   1.920 +                                               out[j+k],opb);
   1.921 +          /*else
   1.922 +            fprintf(stderr,"+!");*/
   1.923 +
   1.924 +#ifdef TRAIN_FLOOR1
   1.925 +          {
   1.926 +            FILE *of;
   1.927 +            char buffer[80];
   1.928 +            sprintf(buffer,"line_%dx%ld_%dsub%d.vqd",
   1.929 +                    vb->pcmend/2,posts-2,class,bookas[k]);
   1.930 +            of=fopen(buffer,"a");
   1.931 +            fprintf(of,"%d\n",out[j+k]);
   1.932 +            fclose(of);
   1.933 +          }
   1.934 +#endif
   1.935 +        }
   1.936 +      }
   1.937 +      j+=cdim;
   1.938 +    }
   1.939 +
   1.940 +    {
   1.941 +      /* generate quantized floor equivalent to what we'd unpack in decode */
   1.942 +      /* render the lines */
   1.943 +      int hx=0;
   1.944 +      int lx=0;
   1.945 +      int ly=post[0]*info->mult;
   1.946 +      int n=ci->blocksizes[vb->W]/2;
   1.947 +
   1.948 +      for(j=1;j<look->posts;j++){
   1.949 +        int current=look->forward_index[j];
   1.950 +        int hy=post[current]&0x7fff;
   1.951 +        if(hy==post[current]){
   1.952 +
   1.953 +          hy*=info->mult;
   1.954 +          hx=info->postlist[current];
   1.955 +
   1.956 +          render_line0(n,lx,hx,ly,hy,ilogmask);
   1.957 +
   1.958 +          lx=hx;
   1.959 +          ly=hy;
   1.960 +        }
   1.961 +      }
   1.962 +      for(j=hx;j<vb->pcmend/2;j++)ilogmask[j]=ly; /* be certain */
   1.963 +      return(1);
   1.964 +    }
   1.965 +  }else{
   1.966 +    oggpack_write(opb,0,1);
   1.967 +    memset(ilogmask,0,vb->pcmend/2*sizeof(*ilogmask));
   1.968 +    return(0);
   1.969 +  }
   1.970 +}
   1.971 +
   1.972 +static void *floor1_inverse1(vorbis_block *vb,vorbis_look_floor *in){
   1.973 +  vorbis_look_floor1 *look=(vorbis_look_floor1 *)in;
   1.974 +  vorbis_info_floor1 *info=look->vi;
   1.975 +  codec_setup_info   *ci=vb->vd->vi->codec_setup;
   1.976 +
   1.977 +  int i,j,k;
   1.978 +  codebook *books=ci->fullbooks;
   1.979 +
   1.980 +  /* unpack wrapped/predicted values from stream */
   1.981 +  if(oggpack_read(&vb->opb,1)==1){
   1.982 +    int *fit_value=_vorbis_block_alloc(vb,(look->posts)*sizeof(*fit_value));
   1.983 +
   1.984 +    fit_value[0]=oggpack_read(&vb->opb,ilog(look->quant_q-1));
   1.985 +    fit_value[1]=oggpack_read(&vb->opb,ilog(look->quant_q-1));
   1.986 +
   1.987 +    /* partition by partition */
   1.988 +    for(i=0,j=2;i<info->partitions;i++){
   1.989 +      int class=info->partitionclass[i];
   1.990 +      int cdim=info->class_dim[class];
   1.991 +      int csubbits=info->class_subs[class];
   1.992 +      int csub=1<<csubbits;
   1.993 +      int cval=0;
   1.994 +
   1.995 +      /* decode the partition's first stage cascade value */
   1.996 +      if(csubbits){
   1.997 +        cval=vorbis_book_decode(books+info->class_book[class],&vb->opb);
   1.998 +
   1.999 +        if(cval==-1)goto eop;
  1.1000 +      }
  1.1001 +
  1.1002 +      for(k=0;k<cdim;k++){
  1.1003 +        int book=info->class_subbook[class][cval&(csub-1)];
  1.1004 +        cval>>=csubbits;
  1.1005 +        if(book>=0){
  1.1006 +          if((fit_value[j+k]=vorbis_book_decode(books+book,&vb->opb))==-1)
  1.1007 +            goto eop;
  1.1008 +        }else{
  1.1009 +          fit_value[j+k]=0;
  1.1010 +        }
  1.1011 +      }
  1.1012 +      j+=cdim;
  1.1013 +    }
  1.1014 +
  1.1015 +    /* unwrap positive values and reconsitute via linear interpolation */
  1.1016 +    for(i=2;i<look->posts;i++){
  1.1017 +      int predicted=render_point(info->postlist[look->loneighbor[i-2]],
  1.1018 +                                 info->postlist[look->hineighbor[i-2]],
  1.1019 +                                 fit_value[look->loneighbor[i-2]],
  1.1020 +                                 fit_value[look->hineighbor[i-2]],
  1.1021 +                                 info->postlist[i]);
  1.1022 +      int hiroom=look->quant_q-predicted;
  1.1023 +      int loroom=predicted;
  1.1024 +      int room=(hiroom<loroom?hiroom:loroom)<<1;
  1.1025 +      int val=fit_value[i];
  1.1026 +
  1.1027 +      if(val){
  1.1028 +        if(val>=room){
  1.1029 +          if(hiroom>loroom){
  1.1030 +            val = val-loroom;
  1.1031 +          }else{
  1.1032 +            val = -1-(val-hiroom);
  1.1033 +          }
  1.1034 +        }else{
  1.1035 +          if(val&1){
  1.1036 +            val= -((val+1)>>1);
  1.1037 +          }else{
  1.1038 +            val>>=1;
  1.1039 +          }
  1.1040 +        }
  1.1041 +
  1.1042 +        fit_value[i]=(val+predicted)&0x7fff;
  1.1043 +        fit_value[look->loneighbor[i-2]]&=0x7fff;
  1.1044 +        fit_value[look->hineighbor[i-2]]&=0x7fff;
  1.1045 +
  1.1046 +      }else{
  1.1047 +        fit_value[i]=predicted|0x8000;
  1.1048 +      }
  1.1049 +
  1.1050 +    }
  1.1051 +
  1.1052 +    return(fit_value);
  1.1053 +  }
  1.1054 + eop:
  1.1055 +  return(NULL);
  1.1056 +}
  1.1057 +
  1.1058 +static int floor1_inverse2(vorbis_block *vb,vorbis_look_floor *in,void *memo,
  1.1059 +                          float *out){
  1.1060 +  vorbis_look_floor1 *look=(vorbis_look_floor1 *)in;
  1.1061 +  vorbis_info_floor1 *info=look->vi;
  1.1062 +
  1.1063 +  codec_setup_info   *ci=vb->vd->vi->codec_setup;
  1.1064 +  int                  n=ci->blocksizes[vb->W]/2;
  1.1065 +  int j;
  1.1066 +
  1.1067 +  if(memo){
  1.1068 +    /* render the lines */
  1.1069 +    int *fit_value=(int *)memo;
  1.1070 +    int hx=0;
  1.1071 +    int lx=0;
  1.1072 +    int ly=fit_value[0]*info->mult;
  1.1073 +    /* guard lookup against out-of-range values */
  1.1074 +    ly=(ly<0?0:ly>255?255:ly);
  1.1075 +
  1.1076 +    for(j=1;j<look->posts;j++){
  1.1077 +      int current=look->forward_index[j];
  1.1078 +      int hy=fit_value[current]&0x7fff;
  1.1079 +      if(hy==fit_value[current]){
  1.1080 +
  1.1081 +        hx=info->postlist[current];
  1.1082 +        hy*=info->mult;
  1.1083 +        /* guard lookup against out-of-range values */
  1.1084 +        hy=(hy<0?0:hy>255?255:hy);
  1.1085 +
  1.1086 +        render_line(n,lx,hx,ly,hy,out);
  1.1087 +
  1.1088 +        lx=hx;
  1.1089 +        ly=hy;
  1.1090 +      }
  1.1091 +    }
  1.1092 +    for(j=hx;j<n;j++)out[j]*=FLOOR1_fromdB_LOOKUP[ly]; /* be certain */
  1.1093 +    return(1);
  1.1094 +  }
  1.1095 +  memset(out,0,sizeof(*out)*n);
  1.1096 +  return(0);
  1.1097 +}
  1.1098 +
  1.1099 +/* export hooks */
  1.1100 +const vorbis_func_floor floor1_exportbundle={
  1.1101 +  &floor1_pack,&floor1_unpack,&floor1_look,&floor1_free_info,
  1.1102 +  &floor1_free_look,&floor1_inverse1,&floor1_inverse2
  1.1103 +};