libs/libvorbis-1.3.2/vq/latticebuild.c

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2017-01-10 04:08:49 +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 Xiph.Org Foundation http://www.xiph.org/ *
* *
********************************************************************
function: utility main for building codebooks from lattice descriptions
last mod: $Id: latticebuild.c 16037 2009-05-26 21:10:58Z xiphmont $
********************************************************************/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <errno.h>
#include "bookutil.h"
/* The purpose of this util is just to finish packaging the
description into a static codebook. It used to count hits for a
histogram, but I've divorced that out to add some flexibility (it
currently generates an equal probability codebook)
command line:
latticebuild description.vql
the lattice description file contains two lines:
<n> <dim> <multiplicitavep> <sequentialp>
<value_0> <value_1> <value_2> ... <value_n-1>
a threshmap (or pigeonmap) struct is generated by latticehint;
there are fun tricks one can do with the threshmap and cascades,
but the utils don't know them...
entropy encoding is done by feeding an entry list collected from a
training set and feeding it to latticetune along with the book.
latticebuild produces a codebook on stdout */
static int ilog(unsigned int v){
int ret=0;
while(v){
ret++;
v>>=1;
}
return(ret);
}
int main(int argc,char *argv[]){
codebook b;
static_codebook c;
double *quantlist;
long *hits;
int entries=-1,dim=-1,quantvals=-1,addmul=-1,sequencep=0;
FILE *in=NULL;
char *line,*name;
long i,j;
memset(&b,0,sizeof(b));
memset(&c,0,sizeof(c));
if(argv[1]==NULL){
fprintf(stderr,"Need a lattice description file on the command line.\n");
exit(1);
}
{
char *ptr;
char *filename=_ogg_calloc(strlen(argv[1])+4,1);
strcpy(filename,argv[1]);
in=fopen(filename,"r");
if(!in){
fprintf(stderr,"Could not open input file %s\n",filename);
exit(1);
}
ptr=strrchr(filename,'.');
if(ptr){
*ptr='\0';
name=strdup(filename);
}else{
name=strdup(filename);
}
}
/* read the description */
line=get_line(in);
if(sscanf(line,"%d %d %d %d",&quantvals,&dim,&addmul,&sequencep)!=4){
if(sscanf(line,"%d %d %d",&quantvals,&dim,&addmul)!=3){
fprintf(stderr,"Syntax error reading description file (line 1)\n");
exit(1);
}
}
entries=pow(quantvals,dim);
c.dim=dim;
c.entries=entries;
c.lengthlist=_ogg_malloc(entries*sizeof(long));
c.maptype=1;
c.q_sequencep=sequencep;
c.quantlist=_ogg_calloc(quantvals,sizeof(long));
quantlist=_ogg_malloc(sizeof(double)*c.dim*c.entries);
hits=_ogg_malloc(c.entries*sizeof(long));
for(j=0;j<entries;j++)hits[j]=1;
for(j=0;j<entries;j++)c.lengthlist[j]=1;
reset_next_value();
line=setup_line(in);
for(j=0;j<quantvals;j++){
char *temp;
if(!line || sscanf(line,"%lf",quantlist+j)!=1){
fprintf(stderr,"Ran out of data on line 2 of description file\n");
exit(1);
}
temp=strchr(line,',');
if(!temp)temp=strchr(line,' ');
if(temp)temp++;
line=temp;
}
/* gen a real quant list from the more easily human-grokked input */
{
double min=quantlist[0];
double mindel=-1;
int fac=1;
for(j=1;j<quantvals;j++)if(quantlist[j]<min)min=quantlist[j];
for(j=0;j<quantvals;j++)
for(i=j+1;i<quantvals;i++)
if(mindel==-1 || fabs(quantlist[j]-quantlist[i])<mindel)
mindel=fabs(quantlist[j]-quantlist[i]);
j=0;
while(j<quantvals){
for(j=0;j<quantvals;j++){
double test=fac*(quantlist[j]-min)/mindel;
if( fabs(rint(test)-test)>.00001f) break;
}
if(fac>100)break;
if(j<quantvals)fac++;
}
mindel/=fac;
fprintf(stderr,"min=%g mindel=%g\n",min,mindel);
c.q_min=_float32_pack(min);
c.q_delta=_float32_pack(mindel);
c.q_quant=0;
min=_float32_unpack(c.q_min);
mindel=_float32_unpack(c.q_delta);
for(j=0;j<quantvals;j++){
c.quantlist[j]=rint((quantlist[j]-min)/mindel);
if(ilog(c.quantlist[j])>c.q_quant)c.q_quant=ilog(c.quantlist[j]);
}
}
/* build the [default] codeword lengths */
memset(c.lengthlist,0,sizeof(long)*entries);
for(i=0;i<entries;i++)hits[i]=1;
build_tree_from_lengths(entries,hits,c.lengthlist);
/* save the book in C header form */
write_codebook(stdout,name,&c);
fprintf(stderr,"\r "
"\nDone.\n");
exit(0);
}