mapping0.c

在x86平台上运行不可信任代码的sandbox。

/********************************************************************
 *                                                                  *
 * 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 1994-2002             *
 * by the XIPHOPHORUS Company http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: channel mapping 0 implementation
 last mod: $Id: mapping0.c 1919 2005-07-24 14:18:04Z baford $

 ********************************************************************/

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <ogg/ogg.h>
#include "vorbis/codec.h"
#include "codec_internal.h"
#include "codebook.h"
#include "window.h"
#include "registry.h"
#include "psy.h"
#include "misc.h"

/* simplistic, wasteful way of doing this (unique lookup for each
   mode/submapping); there should be a central repository for
   identical lookups.  That will require minor work, so I'm putting it
   off as low priority.

   Why a lookup for each backend in a given mode?  Because the
   blocksize is set by the mode, and low backend lookups may require
   parameters from other areas of the mode/mapping */

static void mapping0_free_info(vorbis_info_mapping *i){
  vorbis_info_mapping0 *info=(vorbis_info_mapping0 *)i;
  if(info){
    memset(info,0,sizeof(*info));
    _ogg_free(info);
  }
}

static int ilog(unsigned int v){
  int ret=0;
  if(v)--v;
  while(v){
    ret++;
    v>>=1;
  }
  return(ret);
}

static void mapping0_pack(vorbis_info *vi,vorbis_info_mapping *vm,
			  oggpack_buffer *opb){
  int i;
  vorbis_info_mapping0 *info=(vorbis_info_mapping0 *)vm;

  /* another 'we meant to do it this way' hack...  up to beta 4, we
     packed 4 binary zeros here to signify one submapping in use.  We
     now redefine that to mean four bitflags that indicate use of
     deeper features; bit0:submappings, bit1:coupling,
     bit2,3:reserved. This is backward compatable with all actual uses
     of the beta code. */

  if(info->submaps>1){
    oggpack_write(opb,1,1);
    oggpack_write(opb,info->submaps-1,4);
  }else
    oggpack_write(opb,0,1);

  if(info->coupling_steps>0){
    oggpack_write(opb,1,1);
    oggpack_write(opb,info->coupling_steps-1,8);
    
    for(i=0;i<info->coupling_steps;i++){
      oggpack_write(opb,info->coupling_mag[i],ilog(vi->channels));
      oggpack_write(opb,info->coupling_ang[i],ilog(vi->channels));
    }
  }else
    oggpack_write(opb,0,1);
  
  oggpack_write(opb,0,2); /* 2,3:reserved */

  /* we don't write the channel submappings if we only have one... */
  if(info->submaps>1){
    for(i=0;i<vi->channels;i++)
      oggpack_write(opb,info->chmuxlist[i],4);
  }
  for(i=0;i<info->submaps;i++){
    oggpack_write(opb,0,8); /* time submap unused */
    oggpack_write(opb,info->floorsubmap[i],8);
    oggpack_write(opb,info->residuesubmap[i],8);
  }
}

/* also responsible for range checking */
static vorbis_info_mapping *mapping0_unpack(vorbis_info *vi,oggpack_buffer *opb){
  int i;
  vorbis_info_mapping0 *info=_ogg_calloc(1,sizeof(*info));
  codec_setup_info     *ci=vi->codec_setup;
  memset(info,0,sizeof(*info));

  if(oggpack_read(opb,1))
    info->submaps=oggpack_read(opb,4)+1;
  else
    info->submaps=1;

  if(oggpack_read(opb,1)){
    info->coupling_steps=oggpack_read(opb,8)+1;

    for(i=0;i<info->coupling_steps;i++){
      int testM=info->coupling_mag[i]=oggpack_read(opb,ilog(vi->channels));
      int testA=info->coupling_ang[i]=oggpack_read(opb,ilog(vi->channels));

      if(testM<0 || 
	 testA<0 || 
	 testM==testA || 
	 testM>=vi->channels ||
	 testA>=vi->channels) goto err_out;
    }

  }

  if(oggpack_read(opb,2)>0)goto err_out; /* 2,3:reserved */
    
  if(info->submaps>1){
    for(i=0;i<vi->channels;i++){
      info->chmuxlist[i]=oggpack_read(opb,4);
      if(info->chmuxlist[i]>=info->submaps)goto err_out;
    }
  }
  for(i=0;i<info->submaps;i++){
    oggpack_read(opb,8); /* time submap unused */
    info->floorsubmap[i]=oggpack_read(opb,8);
    if(info->floorsubmap[i]>=ci->floors)goto err_out;
    info->residuesubmap[i]=oggpack_read(opb,8);
    if(info->residuesubmap[i]>=ci->residues)goto err_out;
  }

  return info;

 err_out:
  mapping0_free_info(info);
  return(NULL);
}

#include "os.h"
#include "lpc.h"
#include "lsp.h"
#include "envelope.h"
#include "mdct.h"
#include "psy.h"
#include "scales.h"

#if 0
static long seq=0;
static ogg_int64_t total=0;
static float FLOOR1_fromdB_LOOKUP[256]={
  1.0649863e-07F, 1.1341951e-07F, 1.2079015e-07F, 1.2863978e-07F, 
  1.3699951e-07F, 1.4590251e-07F, 1.5538408e-07F, 1.6548181e-07F, 
  1.7623575e-07F, 1.8768855e-07F, 1.9988561e-07F, 2.128753e-07F, 
  2.2670913e-07F, 2.4144197e-07F, 2.5713223e-07F, 2.7384213e-07F, 
  2.9163793e-07F, 3.1059021e-07F, 3.3077411e-07F, 3.5226968e-07F, 
  3.7516214e-07F, 3.9954229e-07F, 4.2550680e-07F, 4.5315863e-07F, 
  4.8260743e-07F, 5.1396998e-07F, 5.4737065e-07F, 5.8294187e-07F, 
  6.2082472e-07F, 6.6116941e-07F, 7.0413592e-07F, 7.4989464e-07F, 
  7.9862701e-07F, 8.5052630e-07F, 9.0579828e-07F, 9.6466216e-07F, 
  1.0273513e-06F, 1.0941144e-06F, 1.1652161e-06F, 1.2409384e-06F, 
  1.3215816e-06F, 1.4074654e-06F, 1.4989305e-06F, 1.5963394e-06F, 
  1.7000785e-06F, 1.8105592e-06F, 1.9282195e-06F, 2.0535261e-06F, 
  2.1869758e-06F, 2.3290978e-06F, 2.4804557e-06F, 2.6416497e-06F, 
  2.8133190e-06F, 2.9961443e-06F, 3.1908506e-06F, 3.3982101e-06F, 
  3.6190449e-06F, 3.8542308e-06F, 4.1047004e-06F, 4.3714470e-06F, 
  4.6555282e-06F, 4.9580707e-06F, 5.2802740e-06F, 5.6234160e-06F, 
  5.9888572e-06F, 6.3780469e-06F, 6.7925283e-06F, 7.2339451e-06F, 
  7.7040476e-06F, 8.2047000e-06F, 8.7378876e-06F, 9.3057248e-06F, 
  9.9104632e-06F, 1.0554501e-05F, 1.1240392e-05F, 1.1970856e-05F, 
  1.2748789e-05F, 1.3577278e-05F, 1.4459606e-05F, 1.5399272e-05F, 
  1.6400004e-05F, 1.7465768e-05F, 1.8600792e-05F, 1.9809576e-05F, 
  2.1096914e-05F, 2.2467911e-05F, 2.3928002e-05F, 2.5482978e-05F, 
  2.7139006e-05F, 2.8902651e-05F, 3.0780908e-05F, 3.2781225e-05F, 
  3.4911534e-05F, 3.7180282e-05F, 3.9596466e-05F, 4.2169667e-05F, 
  4.4910090e-05F, 4.7828601e-05F, 5.0936773e-05F, 5.4246931e-05F, 
  5.7772202e-05F, 6.1526565e-05F, 6.5524908e-05F, 6.9783085e-05F, 
  7.4317983e-05F, 7.9147585e-05F, 8.4291040e-05F, 8.9768747e-05F, 
  9.5602426e-05F, 0.00010181521F, 0.00010843174F, 0.00011547824F, 
  0.00012298267F, 0.00013097477F, 0.00013948625F, 0.00014855085F, 
  0.00015820453F, 0.00016848555F, 0.00017943469F, 0.00019109536F, 
  0.00020351382F, 0.00021673929F, 0.00023082423F, 0.00024582449F, 
  0.00026179955F, 0.00027881276F, 0.00029693158F, 0.00031622787F, 
  0.00033677814F, 0.00035866388F, 0.00038197188F, 0.00040679456F, 
  0.00043323036F, 0.00046138411F, 0.00049136745F, 0.00052329927F, 
  0.00055730621F, 0.00059352311F, 0.00063209358F, 0.00067317058F, 
  0.00071691700F, 0.00076350630F, 0.00081312324F, 0.00086596457F, 
  0.00092223983F, 0.00098217216F, 0.0010459992F, 0.0011139742F, 
  0.0011863665F, 0.0012634633F, 0.0013455702F, 0.0014330129F, 
  0.0015261382F, 0.0016253153F, 0.0017309374F, 0.0018434235F, 
  0.0019632195F, 0.0020908006F, 0.0022266726F, 0.0023713743F, 
  0.0025254795F, 0.0026895994F, 0.0028643847F, 0.0030505286F, 
  0.0032487691F, 0.0034598925F, 0.0036847358F, 0.0039241906F, 
  0.0041792066F, 0.0044507950F, 0.0047400328F, 0.0050480668F, 
  0.0053761186F, 0.0057254891F, 0.0060975636F, 0.0064938176F, 
  0.0069158225F, 0.0073652516F, 0.0078438871F, 0.0083536271F, 
  0.0088964928F, 0.009474637F, 0.010090352F, 0.010746080F, 
  0.011444421F, 0.012188144F, 0.012980198F, 0.013823725F, 
  0.014722068F, 0.015678791F, 0.016697687F, 0.017782797F, 
  0.018938423F, 0.020169149F, 0.021479854F, 0.022875735F, 
  0.024362330F, 0.025945531F, 0.027631618F, 0.029427276F, 
  0.031339626F, 0.033376252F, 0.035545228F, 0.037855157F, 
  0.040315199F, 0.042935108F, 0.045725273F, 0.048696758F, 
  0.051861348F, 0.055231591F, 0.058820850F, 0.062643361F, 
  0.066714279F, 0.071049749F, 0.075666962F, 0.080584227F, 
  0.085821044F, 0.091398179F, 0.097337747F, 0.10366330F, 
  0.11039993F, 0.11757434F, 0.12521498F, 0.13335215F, 
  0.14201813F, 0.15124727F, 0.16107617F, 0.17154380F, 
  0.18269168F, 0.19456402F, 0.20720788F, 0.22067342F, 
  0.23501402F, 0.25028656F, 0.26655159F, 0.28387361F, 
  0.30232132F, 0.32196786F, 0.34289114F, 0.36517414F, 
  0.38890521F, 0.41417847F, 0.44109412F, 0.46975890F, 
  0.50028648F, 0.53279791F, 0.56742212F, 0.60429640F, 
  0.64356699F, 0.68538959F, 0.72993007F, 0.77736504F, 
  0.82788260F, 0.88168307F, 0.9389798F, 1.F, 
};

#endif 

extern int *floor1_fit(vorbis_block *vb,vorbis_look_floor *look,
		       const float *logmdct,   /* in */
		       const float *logmask);
extern int *floor1_interpolate_fit(vorbis_block *vb,vorbis_look_floor *look,
				   int *A,int *B,
				   int del);
extern int floor1_encode(vorbis_block *vb,vorbis_look_floor *look,
			 int *post,int *ilogmask);


static int mapping0_forward(vorbis_block *vb){
  vorbis_dsp_state      *vd=vb->vd;
  vorbis_info           *vi=vd->vi;
  codec_setup_info      *ci=vi->codec_setup;
  private_state         *b=vb->vd->backend_state;
  vorbis_block_internal *vbi=(vorbis_block_internal *)vb->internal;
  int                    n=vb->pcmend;
  int i,j,k;

  int    *nonzero    = alloca(sizeof(*nonzero)*vi->channels);
  float  **gmdct     = _vorbis_block_alloc(vb,vi->channels*sizeof(*gmdct));
  int    **ilogmaskch= _vorbis_block_alloc(vb,vi->channels*sizeof(*ilogmaskch));
  int ***floor_posts = _vorbis_block_alloc(vb,vi->channels*sizeof(*floor_posts));
  
  float global_ampmax=vbi->ampmax;
  float *local_ampmax=alloca(sizeof(*local_ampmax)*vi->channels);
  int blocktype=vbi->blocktype;

  int modenumber=vb->W;
  vorbis_info_mapping0 *info=ci->map_param[modenumber];
  vorbis_look_psy *psy_look=
    b->psy+blocktype+(vb->W?2:0);

  vb->mode=modenumber;

  for(i=0;i<vi->channels;i++){
    float scale=4.f/n;
    float scale_dB;

    float *pcm     =vb->pcm[i]; 
    float *logfft  =pcm;

    gmdct[i]=_vorbis_block_alloc(vb,n/2*sizeof(**gmdct));

    scale_dB=todB(&scale);

#if 0
    if(vi->channels==2)
      if(i==0)
	_analysis_output("pcmL",seq,pcm,n,0,0,total-n/2);
      else
	_analysis_output("pcmR",seq,pcm,n,0,0,total-n/2);
#endif
  
    /* window the PCM data */
    _vorbis_apply_window(pcm,b->window,ci->blocksizes,vb->lW,vb->W,vb->nW);

#if 0
    if(vi->channels==2)
      if(i==0)
	_analysis_output("windowedL",seq,pcm,n,0,0,total-n/2);
      else
	_analysis_output("windowedR",seq,pcm,n,0,0,total-n/2);
#endif

    /* transform the PCM data */
    /* only MDCT right now.... */
    mdct_forward(b->transform[vb->W][0],pcm,gmdct[i]);
    
    /* FFT yields more accurate tonal estimation (not phase sensitive) */
    drft_forward(&b->fft_look[vb->W],pcm);
    logfft[0]=scale_dB+todB(pcm);
    local_ampmax[i]=logfft[0];
    for(j=1;j<n-1;j+=2){
      float temp=pcm[j]*pcm[j]+pcm[j+1]*pcm[j+1];
      temp=logfft[(j+1)>>1]=scale_dB+.5f*todB(&temp);
      if(temp>local_ampmax[i])local_ampmax[i]=temp;
    }

    if(local_ampmax[i]>0.f)local_ampmax[i]=0.f;
    if(local_ampmax[i]>global_ampmax)global_ampmax=local_ampmax[i];

#if 0
    if(vi->channels==2)
      if(i==0)
	_analysis_output("fftL",seq,logfft,n/2,1,0,0);
      else
	_analysis_output("fftR",seq,logfft,n/2,1,0,0);
#endif

  }
  
  {
    float   *noise        = _vorbis_block_alloc(vb,n/2*sizeof(*noise));
    float   *tone         = _vorbis_block_alloc(vb,n/2*sizeof(*tone));
    
    for(i=0;i<vi->channels;i++){
      /* the encoder setup assumes that all the modes used by any
	 specific bitrate tweaking use the same floor */
      
      int submap=info->chmuxlist[i];
      
      /* the following makes things clearer to *me* anyway */
      float *mdct    =gmdct[i];
      float *logfft  =vb->pcm[i];
      
      float *logmdct =logfft+n/2;
      float *logmask =logfft;

      vb->mode=modenumber;

      floor_posts[i]=_vorbis_block_alloc(vb,PACKETBLOBS*sizeof(**floor_posts));
      memset(floor_posts[i],0,sizeof(**floor_posts)*PACKETBLOBS);
      
      for(j=0;j<n/2;j++)
	logmdct[j]=todB(mdct+j);

#if 0
      if(vi->channels==2){
	if(i==0)
	  _analysis_output("mdctL",seq,logmdct,n/2,1,0,0);
	else
	  _analysis_output("mdctR",seq,logmdct,n/2,1,0,0);
      }else{
	_analysis_output("mdct",seq,logmdct,n/2,1,0,0);
      }
#endif 
      
      /* first step; noise masking.  Not only does 'noise masking'
         give us curves from which we can decide how much resolution
         to give noise parts of the spectrum, it also implicitly hands
         us a tonality estimate (the larger the value in the
         'noise_depth' vector, the more tonal that area is) */

      _vp_noisemask(psy_look,
		    logmdct,
		    noise); /* noise does not have by-frequency offset
                               bias applied yet */
#if 0
      if(vi->channels==2){
	if(i==0)
	  _analysis_output("noiseL",seq,noise,n/2,1,0,0);
	else
	  _analysis_output("noiseR",seq,noise,n/2,1,0,0);
      }
#endif

      /* second step: 'all the other crap'; all the stuff that isn't
         computed/fit for bitrate management goes in the second psy
         vector.  This includes tone masking, peak limiting and ATH */