99d2599b79
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@5996 a1c6a512-1295-4272-9138-f99709370657
84 lines
2.1 KiB
C
84 lines
2.1 KiB
C
/********************************************************************
|
|
* *
|
|
* 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 1994-2002 *
|
|
* BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
|
|
* *
|
|
********************************************************************
|
|
|
|
function: window functions
|
|
|
|
********************************************************************/
|
|
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
#include "os.h"
|
|
#include "misc.h"
|
|
#include "window.h"
|
|
#include "window_lookup.h"
|
|
|
|
const void *_vorbis_window(int type, int left){
|
|
|
|
switch(type){
|
|
case 0:
|
|
|
|
switch(left){
|
|
case 32:
|
|
return vwin64;
|
|
case 64:
|
|
return vwin128;
|
|
case 128:
|
|
return vwin256;
|
|
case 256:
|
|
return vwin512;
|
|
case 512:
|
|
return vwin1024;
|
|
case 1024:
|
|
return vwin2048;
|
|
case 2048:
|
|
return vwin4096;
|
|
case 4096:
|
|
return vwin8192;
|
|
default:
|
|
return(0);
|
|
}
|
|
break;
|
|
default:
|
|
return(0);
|
|
}
|
|
}
|
|
|
|
void _vorbis_apply_window(ogg_int32_t *d,const void *window_p[2],
|
|
long *blocksizes,
|
|
int lW,int W,int nW){
|
|
|
|
LOOKUP_T *window[2]={window_p[0],window_p[1]};
|
|
long n=blocksizes[W];
|
|
long ln=blocksizes[lW];
|
|
long rn=blocksizes[nW];
|
|
|
|
long leftbegin=n/4-ln/4;
|
|
long leftend=leftbegin+ln/2;
|
|
|
|
long rightbegin=n/2+n/4-rn/4;
|
|
long rightend=rightbegin+rn/2;
|
|
|
|
int i,p;
|
|
|
|
for(i=0;i<leftbegin;i++)
|
|
d[i]=0;
|
|
|
|
for(p=0;i<leftend;i++,p++)
|
|
d[i]=MULT31(d[i],window[lW][p]);
|
|
|
|
for(i=rightbegin,p=rn/2-1;i<rightend;i++,p--)
|
|
d[i]=MULT31(d[i],window[nW][p]);
|
|
|
|
for(;i<n;i++)
|
|
d[i]=0;
|
|
}
|