ztscanutil.cpp

《Visual C++小波变换技术与工程实践》靳济芳编著的光盘程序。

    }
  }
  else
  {
    for (c=0; c<mzte_codec.m_iColors; c++) 
    {  	
      for (l=0; l<mzte_codec.m_iWvtDecmpLev;++l)
      {
	for (i=0; i<MAX_NUM_TYPE_CONTEXTS; ++i)
	  acmType[c][l][i].Max_frequency=mzte_codec.m_iAcmMaxFreq[0];
        
      acmSign[c][l].Max_frequency=mzte_codec.m_iAcmMaxFreq[5];

      }

      acmVZ[c].Max_frequency=mzte_codec.m_iAcmMaxFreq[1];
    }
  }
}

Void CVTCCommon::init_acm_maxf_dec()
{
  init_acm_maxf_enc();
}


/********************************************************
  Function Name
  -------------
  Void clear_ZTR_D()

  Arguments
  ---------
  None.

  
  Description
  -----------
  Clear the zerotree descendent marks in the entire image.

  Functions Called
  ----------------
  None.


  Return Value
  ------------
  None.

********************************************************/ 
Void CVTCCommon::clear_ZTR_D(COEFFINFO **coeffinfo, Int width, Int height)
{
  register COEFFINFO **coeff;
  register i,j,dc_h2,dc_w2;

  coeff=coeffinfo;
  dc_h2=mzte_codec.m_iDCHeight<<1;
  dc_w2=mzte_codec.m_iDCWidth<<1;

  for(i=0;i<dc_h2;i++)
    for(j=dc_w2;j<width;j++)
      if(coeff[i][j].type == ZTR_D)
         coeff[i][j].type = UNTYPED;

  for(i=dc_h2;i<height;i++)
    for(j=0;j<width;j++)
      if(coeff[i][j].type == ZTR_D)
         coeff[i][j].type = UNTYPED;
}


//Added by Sarnoff for error resilience, 3/5/99
/* ----------------------------------------------------------------- */
/* ----------------- Error resilience related routines ------------- */
/* ----------------------------------------------------------------- */

/***************************************************/
/* Get the location of a TU, information includes  */
/* band, coordinate, color, size. bbc, 11/6/98     */
/***************************************************/
Void CVTCDecoder::get_TU_location(Int LTU)
{
  Int a,b,dc_h=mzte_codec.m_iDCHeight,dc_w=mzte_codec.m_iDCWidth;

#ifdef _DC_PACKET_
  LTU-=TU_max_dc;  /* bbc, 11/18/98 */
#endif

  if(mzte_codec.m_iScanDirection==0)
  { 
    /* TD case */
    if(LTU==-1){
      start_w=mzte_codec.m_iDCWidth;
      start_h=0;
      TU_band=TU_color=0;
      return;
    }
    a=LTU/9;
    b=LTU/3;
    start_h=a/dc_w;
    start_w=a%dc_w;
    TU_color=b%3;
    switch(TU_band=(LTU%9)%3){
      case 0:
        start_w +=dc_w;
        break;
      case 1:
        start_h +=dc_h;
          break;
      case 2:
        start_h +=dc_h;
        start_w +=dc_w;
    }
  }
  else
  {
    /* BB case */
    Int l;

    a = LTU / dc_h;
    
    if (a==0)
    {
      l = 0;
      TU_color = 0;
    }
    else
    {
      l = (a-1)/3 + 1;
      TU_color = (a-1)%3;
    }
    
    if (TU_color)
      --l;

    band_height = dc_h<<l;

    b = LTU%dc_h;
    start_h = b<<l;  

#if 0
    /* getting next TU in the same band */
    if(LTU==prev_LTU+1){
      if(start_h<band_height){
	start_h +=TU_height;
	if(start_h<band_height-1){
	  prev_LTU=LTU;
	  goto check_packet_bound;
	}
      }
      else{
	start_h +=TU_height;
	if(start_h<2*band_height-1){
	  prev_LTU=LTU;
	  goto check_packet_bound;
	}
      }
    }

    prev_LTU=LTU;
    a=LTU/mzte_codec.m_iDCHeight;
    b=LTU%mzte_codec.m_iDCHeight; /* location (TU_number) in a band */
    
    if(a<3){  /* Lowest Y */
      TU_spa_loc=0;
      band_height=mzte_codec.m_iDCHeight;
      band_width=mzte_codec.m_iDCWidth;
      TU_color=0; TU_band=a;
      TU_height=1;
    }
    else{
      TU_spa_loc=(a-3)/9+1;
      TU_color=((a-3)/3)%3;
      TU_band=(a-3)%3;
      if(TU_color==0){
	band_height=mzte_codec.m_iDCHeight<<TU_spa_loc;
	band_width=mzte_codec.m_iDCWidth<<TU_spa_loc;
	TU_height=1<<TU_spa_loc;
      }
      else{
	band_height=mzte_codec.m_iDCHeight<<(TU_spa_loc-1);
	band_width=mzte_codec.m_iDCWidth<<(TU_spa_loc-1);
	TU_height=1<<(TU_spa_loc-1);
      }
    }
    
    switch(TU_band){
      case 0:
	start_h=b*TU_height;
	start_w=band_width;
	break;
      case 1:
	start_h=band_height+b*TU_height;
	start_w=0;
	break;
      case 2:
	start_h=band_height+b*TU_height;
	start_w=band_width;
	break;
    }
    
  check_packet_bound:
    /* Find or update the packet boundary, for determining */
    /* context model in arithmetic coding, bbc, 10/5/98 */
    if(TU_first !=packet_TU_first || packet_band !=TU_band){
      packet_TU_first=TU_first;
      packet_band=TU_band;
      packet_top=start_h;
      packet_left=start_w;
    }
#endif
  }
}


#if 0 // not used currently
/**************************************************/
/* Function to check if a coefficient is at the   */
/* position to check end of segment, bbc, 11/6/98 */
/**************************************************/
/* may not need this any more */
Int need_check_segment_end(Int h,Int w,Int color)
{
  int block_size=16;

  if(wvt_level==0)  /* no checking needed for root band */
    return 0;

  switch(subband_loc){
    case 0:  /* LH */
      w-=level_w;
      break;
    case 1:  /* HL */
      h-=level_h;
      break;
    case 2:  /* HH */
      h-=level_h;
      w-=level_w;
      break;
    default:
      errorHandler("%d is not a choice for subband_loc.",subband_loc);
  }

  if(wvt_level<=3)
    block_size=1<<wvt_level;

  if((color == 0 && wvt_level==mzte_codec.wvtDecompLev-1) ||
     (color != 0 && wvt_level==mzte_codec.wvtDecompLev-2)){
    if(!((h+1)%block_size || (w+1)%block_size)){
      if(h+1 != level_h || w+1 != level_w)
        return 1;
    }
    return 0;
  }
  else
    return (!((h+1)%block_size || (w+1)%block_size));
}

#endif 


/**********************************************/
/* Record the location of previously detected */
/* good segment for TD mode, bbc, 10/23/98    */
/**********************************************/
Void CVTCDecoder::set_prev_good_TD_segment(Int TU,int h,int w)
{
  prev_good_TU=TU;
  prev_good_height=h;
  prev_good_width=w;
}

/**********************************************/
/* Record the location of previously detected */
/* good segment for BB mode, ph, 11/19/98     */
/**********************************************/
Void CVTCDecoder::set_prev_good_BB_segment(Int TU,int h,int w)
{
  prev_good_TU=TU;
  prev_good_height=h;
  prev_good_width=w;
}
//End: Added by Sarnoff for error resilience, 3/5/99