/********************************************************************
* *
* THIS FILE IS PART OF THE OggVorbis 'TREMOR' 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 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2003 *
* BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
* *
********************************************************************
function: residue backend 0, 1 and 2 implementation
********************************************************************/
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "ogg.h"
#include "ivorbiscodec.h"
#include "codec_internal.h"
#include "codebook.h"
#include "misc.h"
#include "os.h"
void res_clear_info(vorbis_info_residue *info){
if(info){
if(info->stagemasks)_ogg_free(info->stagemasks);
if(info->stagebooks)_ogg_free(info->stagebooks);
memset(info,0,sizeof(*info));
}
}
static int ilog(unsigned int v){
int ret=0;
while(v){
ret++;
v>>=1;
}
return(ret);
}
/* vorbis_info is for range checking */
int res_unpack(vorbis_info_residue *info,
vorbis_info *vi,oggpack_buffer *opb){
int j,k;
codec_setup_info *ci=(codec_setup_info *)vi->codec_setup;
memset(info,0,sizeof(*info));
info->type=oggpack_read(opb,16);
if(info->type>2 || info->type<0)goto errout;
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);
if(info->groupbook>=ci->books)goto errout;
info->stagemasks=_ogg_malloc(info->partitions*sizeof(*info->stagemasks));
info->stagebooks=_ogg_malloc(info->partitions*8*sizeof(*info->stagebooks));
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->stagemasks[j]=cascade;
}
for(j=0;j<info->partitions;j++){
for(k=0;k<8;k++){
if((info->stagemasks[j]>>k)&1){
unsigned char book=oggpack_read(opb,8);
if(book>=ci->books)goto errout;
info->stagebooks[j*8+k]=book;
if(k+1>info->stages)info->stages=k+1;
}else
info->stagebooks[j*8+k]=0xff;
}
}
if(oggpack_eop(opb))goto errout;
return 0;
errout:
res_clear_info(info);
return 1;
}
int res_inverse(vorbis_dsp_state *vd,vorbis_info_residue *info,
ogg_int32_t **in,int *nonzero,int ch){
int i,j,k,s,used=0;
codec_setup_info *ci=(codec_setup_info *)vd->vi->codec_setup;
codebook *phrasebook=ci->book_param+info->groupbook;
int samples_per_partition=info->grouping;
int partitions_per_word=phrasebook->dim;
int pcmend=ci->blocksizes[vd->W];
if(info->type<2){
int max=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;
for(i=0;i<ch;i++)
if(nonzero[i])
in[used++]=in[i];
ch=used;
if(used){
char **partword=(char **)alloca(ch*sizeof(*partword));
for(j=0;j<ch;j++)
partword[j]=(char *)alloca(partwords*partitions_per_word*
sizeof(*partword[j]));
for(s=0;s<info->stages;s++){
for(i=0;i<partvals;){
if(s==0){
/* fetch the partition word for each channel */
partword[0][i+partitions_per_word-1]=1;
for(k=partitions_per_word-2;k>=0;k--)
partword[0][i+k]=partword[0][i+k+1]*info->partitions;
for(j=1;j<ch;j++)
for(k=partitions_per_word-1;k>=0;k--)
partword[j][i+k]=partword[j-1][i+k];
for(j=0;j<ch;j++){
int temp=vorbis_book_decode(phrasebook,&vd->opb);
if(oggpack_eop(&vd->opb))goto eopbreak;
/* this can be done quickly in assembly due to the quotient
always being at most six bits */
for(k=0;k<partitions_per_word;k++){
ogg_uint32_t div=partword[j][i+k];
partword[j][i+k]=temp/div;
temp-=partword[j][i+k]*div;
}
}
}
/* 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->stagemasks[partword[j][i]]&(1<<s)){
codebook *stagebook=ci->book_param+
info->stagebooks[(partword[j][i]<<3)+s];
if(info->type){
if(vorbis_book_decodev_add(stagebook,in[j]+offset,&vd->opb,
samples_per_partition,-8)==-1)
goto eopbreak;
}else{
if(vorbis_book_decodevs_add(stagebook,in[j]+offset,&vd->opb,
samples_per_partition,-8)==-1)
goto eopbreak;
}
}
}
}
}
}
}
}else{
int max=(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;
char *partword=
(char *)alloca(partwords*partitions_per_word*sizeof(*partword));
int beginoff=info->begin/ch;
for(i=0;i<ch;i++)if(nonzero[i])break;
if(i==ch)return(0); /* no nonzero vectors */
samples_per_partition/=ch;
for(s=0;s<info->stages;s++){
for(i=0;i<partvals;){
if(s==0){
int temp;
partword[i+partitions_per_word-1]=1;
for(k=partitions_per_word-2;k>=0;k--)
partword[i+k]=partword[i+k+1]*info->partitions;
/* fetch the partition word */
temp=vorbis_book_decode(phrasebook,&vd->opb);
if(temp==-1)goto eopbreak;
/* this can be done quickly in assembly due to the quotient
always being at most six bits */
for(k=0;k<partitions_per_word;k++){
ogg_uint32_t div=partword[i+k];
partword[i+k]=temp/div;
temp-=partword[i+k]*div;
}
}
/* now we decode residual values for the partitions */
for(k=0;k<partitions_per_word && i<partvals;k++,i++){
if(info->stagemasks[partword[i]]&(1<<s)){
codebook *stagebook=ci->book_param+
info->stagebooks[(partword[i]<<3)+s];
if(vorbis_book_decodevv_add(stagebook,in,
i*samples_per_partition+beginoff,ch,
&vd->opb,
samples_per_partition,-8)==-1)
goto eopbreak;
}
}
}
}
}
}
errout:
eopbreak:
return 0;
}