st/libs/libvorbis-1.1.2/vq/latticehint.c

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2008-04-04 00:00:00 +00:00
/********************************************************************
* *
* 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 1994-2001 *
* by the XIPHOPHORUS Company http://www.xiph.org/ *
* *
********************************************************************
function: utility main for building thresh/pigeonhole encode hints
last mod: $Id: latticehint.c 7187 2004-07-20 07:24:27Z xiphmont $
********************************************************************/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <errno.h>
#include "../lib/scales.h"
#include "bookutil.h"
#include "vqgen.h"
#include "vqsplit.h"
/* The purpose of this util is to build encode hints for lattice
codebooks so that brute forcing each codebook entry isn't needed.
Threshhold hints are for books in which each scalar in the vector
is independant (eg, residue) and pigeonhole lookups provide a
minimum error fit for words where the scalars are interdependant
(each affecting the fit of the next in sequence) as in an LSP
sequential book (or can be used along with a sparse threshhold map,
like a splitting tree that need not be trained)
If the input book is non-sequential, a threshhold hint is built.
If the input book is sequential, a pigeonholing hist is built.
If the book is sparse, a pigeonholing hint is built, possibly in addition
to the threshhold hint
command line:
latticehint book.vqh [threshlist]
latticehint produces book.vqh on stdout */
static int longsort(const void *a, const void *b){
return(**((long **)a)-**((long **)b));
}
static int addtosearch(int entry,long **tempstack,long *tempcount,int add){
long *ptr=tempstack[entry];
long i=tempcount[entry];
if(ptr){
while(i--)
if(*ptr++==add)return(0);
tempstack[entry]=_ogg_realloc(tempstack[entry],
(tempcount[entry]+1)*sizeof(long));
}else{
tempstack[entry]=_ogg_malloc(sizeof(long));
}
tempstack[entry][tempcount[entry]++]=add;
return(1);
}
static void setvals(int dim,encode_aux_pigeonhole *p,
long *temptrack,float *tempmin,float *tempmax,
int seqp){
int i;
float last=0.f;
for(i=0;i<dim;i++){
tempmin[i]=(temptrack[i])*p->del+p->min+last;
tempmax[i]=tempmin[i]+p->del;
if(seqp)last=tempmin[i];
}
}
/* note that things are currently set up such that input fits that
quantize outside the pigeonmap are dropped and brute-forced. So we
can ignore the <0 and >=n boundary cases in min/max error */
static float minerror(int dim,float *a,encode_aux_pigeonhole *p,
long *temptrack,float *tempmin,float *tempmax){
int i;
float err=0.f;
for(i=0;i<dim;i++){
float eval=0.f;
if(a[i]<tempmin[i]){
eval=tempmin[i]-a[i];
}else if(a[i]>tempmax[i]){
eval=a[i]-tempmax[i];
}
err+=eval*eval;
}
return(err);
}
static float maxerror(int dim,float *a,encode_aux_pigeonhole *p,
long *temptrack,float *tempmin,float *tempmax){
int i;
float err=0.f,eval;
for(i=0;i<dim;i++){
if(a[i]<tempmin[i]){
eval=tempmax[i]-a[i];
}else if(a[i]>tempmax[i]){
eval=a[i]-tempmin[i];
}else{
float t1=a[i]-tempmin[i];
eval=tempmax[i]-a[i];
if(t1>eval)eval=t1;
}
err+=eval*eval;
}
return(err);
}
int main(int argc,char *argv[]){
codebook *b;
static_codebook *c;
int entries=-1,dim=-1;
float min,del;
char *name;
long i,j;
float *suggestions;
int suggcount=0;
if(argv[1]==NULL){
fprintf(stderr,"Need a lattice book on the command line.\n");
exit(1);
}
{
char *ptr;
char *filename=strdup(argv[1]);
b=codebook_load(filename);
c=(static_codebook *)(b->c);
ptr=strrchr(filename,'.');
if(ptr){
*ptr='\0';
name=strdup(filename);
}else{
name=strdup(filename);
}
}
if(c->maptype!=1){
fprintf(stderr,"Provided book is not a latticebook.\n");
exit(1);
}
entries=b->entries;
dim=b->dim;
min=_float32_unpack(c->q_min);
del=_float32_unpack(c->q_delta);
/* Do we want to gen a threshold hint? */
if(c->q_sequencep==0){
/* yes. Discard any preexisting threshhold hint */
long quantvals=_book_maptype1_quantvals(c);
long **quantsort=alloca(quantvals*sizeof(long *));
encode_aux_threshmatch *t=_ogg_calloc(1,sizeof(encode_aux_threshmatch));
c->thresh_tree=t;
fprintf(stderr,"Adding threshold hint to %s...\n",name);
/* partial/complete suggestions */
if(argv[2]){
char *ptr=strdup(argv[2]);
suggestions=alloca(sizeof(float)*quantvals);
for(suggcount=0;ptr && suggcount<quantvals;suggcount++){
char *ptr2=strchr(ptr,',');
if(ptr2)*ptr2++='\0';
suggestions[suggcount]=atof(ptr);
ptr=ptr2;
}
}
/* simplest possible threshold hint only */
t->quantthresh=_ogg_calloc(quantvals-1,sizeof(float));
t->quantmap=_ogg_calloc(quantvals,sizeof(int));
t->threshvals=quantvals;
t->quantvals=quantvals;
/* the quantvals may not be in order; sort em first */
for(i=0;i<quantvals;i++)quantsort[i]=c->quantlist+i;
qsort(quantsort,quantvals,sizeof(long *),longsort);
/* ok, gen the map and thresholds */
for(i=0;i<quantvals;i++)t->quantmap[i]=quantsort[i]-c->quantlist;
for(i=0;i<quantvals-1;i++){
float v1=*(quantsort[i])*del+min;
float v2=*(quantsort[i+1])*del+min;
for(j=0;j<suggcount;j++)
if(v1<suggestions[j] && suggestions[j]<v2){
t->quantthresh[i]=suggestions[j];
break;
}
if(j==suggcount){
t->quantthresh[i]=(v1+v2)*.5;
}
}
}
/* Do we want to gen a pigeonhole hint? */
#if 0
for(i=0;i<entries;i++)if(c->lengthlist[i]==0)break;
if(c->q_sequencep || i<entries){
long **tempstack;
long *tempcount;
long *temptrack;
float *tempmin;
float *tempmax;
long totalstack=0;
long pigeons;
long subpigeons;
long quantvals=_book_maptype1_quantvals(c);
int changep=1,factor;
encode_aux_pigeonhole *p=_ogg_calloc(1,sizeof(encode_aux_pigeonhole));
c->pigeon_tree=p;
fprintf(stderr,"Adding pigeonhole hint to %s...\n",name);
/* the idea is that we quantize uniformly, even in a nonuniform
lattice, so that quantization of one scalar has a predictable
result on the next sequential scalar in a greedy matching
algorithm. We generate a lookup based on the quantization of
the vector (pigeonmap groups quantized entries together) and
list the entries that could possible be the best fit for any
given member of that pigeonhole. The encode process then has a
much smaller list to brute force */
/* find our pigeonhole-specific quantization values, fill in the
quant value->pigeonhole map */
factor=3;
p->del=del;
p->min=min;
p->quantvals=quantvals;
{
int max=0;
for(i=0;i<quantvals;i++)if(max<c->quantlist[i])max=c->quantlist[i];
p->mapentries=max;
}
p->pigeonmap=_ogg_malloc(p->mapentries*sizeof(long));
p->quantvals=(quantvals+factor-1)/factor;
/* pigeonhole roughly on the boundaries of the quantvals; the
exact pigeonhole grouping is an optimization issue, not a
correctness issue */
for(i=0;i<p->mapentries;i++){
float thisval=del*i+min; /* middle of the quant zone */
int quant=0;
float err=fabs(c->quantlist[0]*del+min-thisval);
for(j=1;j<quantvals;j++){
float thiserr=fabs(c->quantlist[j]*del+min-thisval);
if(thiserr<err){
quant=j/factor;
err=thiserr;
}
}
p->pigeonmap[i]=quant;
}
/* pigeonmap complete. Now do the grungy business of finding the
entries that could possibly be the best fit for a value appearing
in the pigeonhole. The trick that allows the below to work is the
uniform quantization; even though the scalars may be 'sequential'
(each a delta from the last), the uniform quantization means that
the error variance is *not* dependant. Given a pigeonhole and an
entry, we can find the minimum and maximum possible errors
(relative to the entry) for any point that could appear in the
pigeonhole */
/* must iterate over both pigeonholes and entries */
/* temporarily (in order to avoid thinking hard), we grow each
pigeonhole seperately, the build a stack of 'em later */
pigeons=1;
subpigeons=1;
for(i=0;i<dim;i++)subpigeons*=p->mapentries;
for(i=0;i<dim;i++)pigeons*=p->quantvals;
temptrack=_ogg_calloc(dim,sizeof(long));
tempmin=_ogg_calloc(dim,sizeof(float));
tempmax=_ogg_calloc(dim,sizeof(float));
tempstack=_ogg_calloc(pigeons,sizeof(long *));
tempcount=_ogg_calloc(pigeons,sizeof(long));
while(1){
float errorpost=-1;
char buffer[80];
/* map our current pigeonhole to a 'big pigeonhole' so we know
what list we're after */
int entry=0;
for(i=dim-1;i>=0;i--)entry=entry*p->quantvals+p->pigeonmap[temptrack[i]];
setvals(dim,p,temptrack,tempmin,tempmax,c->q_sequencep);
sprintf(buffer,"Building pigeonhole search list [%ld]...",totalstack);
/* Search all entries to find the one with the minimum possible
maximum error. Record that error */
for(i=0;i<entries;i++){
if(c->lengthlist[i]>0){
float this=maxerror(dim,b->valuelist+i*dim,p,
temptrack,tempmin,tempmax);
if(errorpost==-1 || this<errorpost)errorpost=this;
spinnit(buffer,subpigeons);
}
}
/* Our search list will contain all entries with a minimum
possible error <= our errorpost */
for(i=0;i<entries;i++)
if(c->lengthlist[i]>0){
spinnit(buffer,subpigeons);
if(minerror(dim,b->valuelist+i*dim,p,
temptrack,tempmin,tempmax)<errorpost)
totalstack+=addtosearch(entry,tempstack,tempcount,i);
}
for(i=0;i<dim;i++){
temptrack[i]++;
if(temptrack[i]<p->mapentries)break;
temptrack[i]=0;
}
if(i==dim)break;
subpigeons--;
}
fprintf(stderr,"\r "
"\rTotal search list size (all entries): %ld\n",totalstack);
/* pare the index of lists for improbable quantizations (where
improbable is determined by c->lengthlist; we assume that
pigeonholing is in sync with the codeword cells, which it is */
/*for(i=0;i<entries;i++){
float probability= 1.f/(1<<c->lengthlist[i]);
if(c->lengthlist[i]==0 || probability*entries<cutoff){
totalstack-=tempcount[i];
tempcount[i]=0;
}
}*/
/* pare the list of shortlists; merge contained and similar lists
together */
p->fitmap=_ogg_malloc(pigeons*sizeof(long));
for(i=0;i<pigeons;i++)p->fitmap[i]=-1;
while(changep){
char buffer[80];
changep=0;
for(i=0;i<pigeons;i++){
if(p->fitmap[i]<0 && tempcount[i]){
for(j=i+1;j<pigeons;j++){
if(p->fitmap[j]<0 && tempcount[j]){
/* is one list a superset, or are they sufficiently similar? */
int amiss=0,bmiss=0,ii,jj;
for(ii=0;ii<tempcount[i];ii++){
for(jj=0;jj<tempcount[j];jj++)
if(tempstack[i][ii]==tempstack[j][jj])break;
if(jj==tempcount[j])amiss++;
}
for(jj=0;jj<tempcount[j];jj++){
for(ii=0;ii<tempcount[i];ii++)
if(tempstack[i][ii]==tempstack[j][jj])break;
if(ii==tempcount[i])bmiss++;
}
if(amiss==0 ||
bmiss==0 ||
(amiss*2<tempcount[i] && bmiss*2<tempcount[j] &&
tempcount[i]+bmiss<entries/30)){
/*superset/similar Add all of one to the other. */
for(jj=0;jj<tempcount[j];jj++)
totalstack+=addtosearch(i,tempstack,tempcount,
tempstack[j][jj]);
totalstack-=tempcount[j];
p->fitmap[j]=i;
changep=1;
}
}
}
sprintf(buffer,"Consolidating [%ld total, %s]... ",totalstack,
changep?"reit":"nochange");
spinnit(buffer,pigeons-i);
}
}
}
/* repack the temp stack in final form */
fprintf(stderr,"\r "
"\rFinal total list size: %ld\n",totalstack);
p->fittotal=totalstack;
p->fitlist=_ogg_malloc((totalstack+1)*sizeof(long));
p->fitlength=_ogg_malloc(pigeons*sizeof(long));
{
long usage=0;
for(i=0;i<pigeons;i++){
if(p->fitmap[i]==-1){
if(tempcount[i])
memcpy(p->fitlist+usage,tempstack[i],tempcount[i]*sizeof(long));
p->fitmap[i]=usage;
p->fitlength[i]=tempcount[i];
usage+=tempcount[i];
if(usage>totalstack){
fprintf(stderr,"Internal error; usage>totalstack\n");
exit(1);
}
}else{
p->fitlength[i]=p->fitlength[p->fitmap[i]];
p->fitmap[i]=p->fitmap[p->fitmap[i]];
}
}
}
}
#endif
write_codebook(stdout,name,c);
fprintf(stderr,"\r "
"\nDone.\n");
exit(0);
}