ztscan_enc.cpp

此源码是在VC平台下,实现MPEG4编解码的源码

		{
		  /* LH */
		  encodeMQBlocks(h,w,n);
		  
		  /* HL */
		  h += ac_h;
		  w -= ac_w;
		  encodeMQBlocks(h,w,n);
		  
		  /* HH */
		  w += ac_w;
		  encodeMQBlocks(h,w,n);
		  
		  /* Set h back to where it started. w is already there */
		  h -= ac_h;
		}
    }

    /* update ranges */
    acH=acH2;
    acW=acW2;
    acW2<<=1;
    acH2<<=1;

    ++layer;
  }

  for (color=0; color<NCOL; ++color)
    probModelFreeMQ(color);

}




/********************************************************
  Function Name
  -------------
  static Void encode_pixel_MQ_band(Int h,Int w)

  Arguments
  ---------
  Int h,Int w - position of a pixel in height and width
  
  Description
  -----------
  Encoding the type and/or value of a coefficient, a
  recursive function, multi quant mode.

  Functions Called
  ----------------
  mzte_ac_encode_symbol()
  mark_ZTR_D()
  mag_sign_encode_MQ()
 
  Return Value
  ------------
  None.

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

Void CVTCEncoder::encode_pixel_MQ(Int h,Int w)
{
  Int zt_type;

  /*~~~~~~~~~~~~~~~~~ zerotree descendent or skip  ~~~~~~~~~~~~~~~~~~~*/
  if(coeffinfo[h][w].type==ZTR_D)
    return;

  /*~~~~~~~~~~~~~~ encode zero tree symbol ~~~~~~~~~~~~~~~~~~*/
  if (IS_RESID(w,h,color))
  {
    zt_type = VAL;
  }
  else
  {
    Int czt_type; /* what to put on bitstream */
    Int l;

    l=xy2wvtDecompLev(w,h);  

    zt_type = coeffinfo[h][w].type;
#ifdef _SHAPE_
    if(coeffinfo[h][w].mask==1) /* skip out-node */  
#endif
      switch(coeffinfo[h][w].state)
      {
	case S_INIT:
	  czt_type=zt_type;
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_INIT],czt_type);
	  break;
	case S_ZTR:
	  czt_type=zt_type;
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_ZTR],czt_type);
	  break;
	case S_ZTR_D:
	  czt_type=zt_type;
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_ZTR_D],czt_type);
	  break;
	case S_IZ:
	  czt_type = (zt_type!=IZ);
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_IZ],czt_type);
	  break;
	case S_LINIT: 
	  czt_type = (zt_type!=ZTR);
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LINIT],czt_type);
	  break;
	case S_LZTR:
	  czt_type = (zt_type!=ZTR);
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LZTR],czt_type);
	  break;
	case S_LZTR_D:
	  czt_type = (zt_type!=ZTR);
	  mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LZTR_D],czt_type);
	  break;
	default:
	  errorHandler("Invalid state (%d) in multi-quant encoding.", 
		       coeffinfo[h][w].state);
      }
  }


  /*~~~~~~~~~~~~~~~~ mark ztr_d and encode magnitudes ~~~~~~~~~~~~~~~~~*/
  switch(zt_type)
  {
    case ZTR:
    case ZTR_D:
#ifdef _SHAPE_
      if(coeffinfo[h][w].mask==1) /* mark ZTR-D for in-node root */
#endif
	mark_ZTR_D(h,w);
    case IZ:
      return;
    case VZTR:
      mark_ZTR_D(h,w);
    case VAL:
#ifdef _SHAPE_
      if(coeffinfo[h][w].mask==1) /* only code for in-node*/
#endif
	mag_sign_encode_MQ(h,w);
      break;
    default:
      errorHandler("Invalid type (%d) in multi-quant encoding.", zt_type);     
  }
}



/**********************************************************************/
/***************       MQ TREE         ********************************/
/**********************************************************************/


/********************************************************
  Function Name
  -------------
  static Void cachb_encode_MQ_tree()

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

  Description
  -----------
  Encode AC information for all color components for spatial level. 
  Multiple quant, bandwise scan.

  Functions Called
  ----------------
  clear_ZTR_D();
  encode_pixel_MQ_tree()

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

********************************************************/ 
// hjlee 0901
Void CVTCEncoder::cachb_encode_MQ_tree()
{
  Int h,w, dc_h, dc_w;

  /* clear the ZTR_D type from the previous pass */
  for (color=0; color<NCOL; ++color)
  {      
    coeffinfo=mzte_codec.m_SPlayer[color].coeffinfo;
    height=mzte_codec.m_SPlayer[color].height;
    width=mzte_codec.m_SPlayer[color].width;

    clear_ZTR_D(coeffinfo, width, height);
  }

  for (color=0; color<NCOL; ++color)
    probModelInitMQ(color);

  /* ac_h, ac_w init */
  dc_h=mzte_codec.m_iDCHeight;
  dc_w=mzte_codec.m_iDCWidth;

  for (h=0; h<dc_h; ++h)
    for (w=0; w<dc_w; ++w)
    {
      for (color=0; color<NCOL; ++color)
      {      
	SNR_IMAGE *snr_image;
	Int tw,sw,sh,n; // 1124
	
	snr_image=&(mzte_codec.m_SPlayer[color].SNRlayer.snr_image);
	
	coeffinfo=mzte_codec.m_SPlayer[color].coeffinfo;
	height=mzte_codec.m_SPlayer[color].height;
	width=mzte_codec.m_SPlayer[color].width;
      
	setProbModelsMQ(color);

	/* LH */
	n = 0;
	for (tw=mzte_codec.m_iDCWidth; tw < width; tw<<=1)
	{
	  sh = h << n;
	  sw = (w+dc_w) << n;
	  encodeMQBlocks(sh,sw,n);
	  n++;
	}
	/* HL */
	n = 0;
	for (tw=mzte_codec.m_iDCWidth; tw < width; tw<<=1)
	{
	  sh = (h+dc_h) << n;
	  sw = w << n;
	  encodeMQBlocks(sh,sw,n);
	  n++;
	}
	/* HH */
	n = 0;
	for (tw=mzte_codec.m_iDCWidth; tw < width; tw<<=1)
	{
	  sh = (h+dc_h) << n;
	  sw = (w+dc_w) << n;
	  encodeMQBlocks(sh,sw,n);
	  n++;
	}
	
#if 0
	encode_pixel_MQ_tree(h,w+dc_w);           /* LH */
	encode_pixel_MQ_tree(h+dc_h,w);           /* HL */
	encode_pixel_MQ_tree(h+dc_h,w+dc_w);      /* HH */
#endif

      }
    }

  for (color=0; color<NCOL; ++color)
    probModelFreeMQ(color);
}


#if 0
/********************************************************
  Function Name
  -------------
  static Void encode_pixel_MQ_tree(Int h,Int w)

  Arguments
  ---------
  Int h,Int w - position of a pixel in height and width
  
  Description
  -----------
  Encoding the type and/or value of a coefficient, a
  recursive function, multi quant mode.

  Functions Called
  ----------------
  mzte_ac_encode_symbol()
  mark_ZTR_D()
  mag_sign_encode_MQ()
 
  Return Value
  ------------
  None.

********************************************************/ 
// hjlee 0901


Void CVTCEncoder::encode_pixel_MQ_tree(Int h0,Int w0)
{
  Int zt_type, h, w, k;
  Int dcc[4]; /* Don't Code Children */
  Int nSib; /* number siblings */

  nSib = (h0<(mzte_codec.m_iDCHeight<<1) && w0<(mzte_codec.m_iDCWidth<<1)) ? 1 : 4;

  /********************* CODE SIBLINGS *****************************/
  for (k=0; k<nSib; ++k)
  {
    h = h0 + (k/2);
    w = w0 + (k%2);

    /* encode zero tree symbol */  
    if (IS_RESID(w,h,color))
    {
      zt_type = VAL;
    }
    else
    {
      Int czt_type; /* what to put on bitstream */
      Int l;

      l=xy2wvtDecompLev(w,h);  

      zt_type = coeffinfo[h][w].type;
#ifdef _SHAPE_
      if(coeffinfo[h][w].mask==1) /* skip out-node */  
#endif      
	switch(coeffinfo[h][w].state)
	{
	  case S_INIT:
	    czt_type=zt_type;
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_INIT],czt_type);
	    break;
	  case S_ZTR:
	    czt_type=zt_type;
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_ZTR],czt_type);
	    break;
	  case S_ZTR_D:
	    czt_type=zt_type;
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_ZTR_D],czt_type);
	    break;
	  case S_IZ:
	    czt_type = (zt_type!=IZ);
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_IZ],czt_type);
	    break;
	  case S_LINIT: 
	    czt_type = (zt_type!=ZTR);
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LINIT],czt_type);
	    break;
	  case S_LZTR:
	    czt_type = (zt_type!=ZTR);
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LZTR],czt_type);
	    break;
	  case S_LZTR_D:
	    czt_type = (zt_type!=ZTR);
	    mzte_ac_encode_symbol(&ace,acm_type[l][CONTEXT_LZTR_D],czt_type);
	    break;
	  default:
	    errorHandler("Invalid state (%d) in multi-quant encoding.", 
			 coeffinfo[h][w].state);
	}
    }
    
    /* mark ztr_d and encode magnitudes */
    switch(zt_type)
    {
      case ZTR:
#ifdef _SHAPE_
	if(coeffinfo[h][w].mask==1) {
#endif
	  dcc[k]=1;
	  mark_ZTR_D(h,w);
#ifdef _SHAPE_
	}
	else
	  dcc[k]=0;
#endif
	break;
      case IZ:
	dcc[k]=0;
	break;
      case VZTR:
	dcc[k]=1;
	mark_ZTR_D(h,w);
#ifdef _SHAPE_
	if(coeffinfo[h][w].mask==1) /* only code for in-node */
#endif
	  mag_sign_encode_MQ(h,w);
	break;
      case VAL:
	dcc[k]=0;
#ifdef _SHAPE_
	if(coeffinfo[h][w].mask==1) /* only code for in-node*/
#endif
	  mag_sign_encode_MQ(h,w);
	break;
      default:
	errorHandler("Invalid type in multi quant decoding.");     
    }
  }


  /********************* CODE CHILDREN *****************************/
  if (!IS_STATE_LEAF(coeffinfo[h0][w0].state))
  {
    Int i, j;

    for (k=0; k<nSib; ++k)
    {
      if (dcc[k]==0)
      {
	h = h0 + (k/2);
	w = w0 + (k%2);  
	
	/* scan children */
	i=h<<1; j=w<<1;
	encode_pixel_MQ_tree(i,j);
      }
    }
  }
}

#endif


/********************************************************
  Function Name
  -------------
  static Void  mag_sign_encode_MQ(Int h,Int w)

  Arguments
  ---------
  Int h,Int w - position of a pixel

  Description
  -----------
  Encode the value of a coefficient.

  Functions Called
  ----------------
  mzte_ac_encode_symbol()

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

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


Void CVTCEncoder::mag_sign_encode_MQ(Int h,Int w)
{
  Int val,v_sign;
  Int l;

  if(coeffinfo[h][w].skip)
    return;
    
  l=xy2wvtDecompLev(w,h);  

  if((val=coeffinfo[h][w].quantized_value)>=0)
    v_sign=0;
  else
  {
    val=-val;
    v_sign=1;
  }
  
  /* code magnitude */

  if (IS_RESID(w,h,color))
  {
    bitplane_res_encode(val,l,WVTDECOMP_RES_NUMBITPLANES(color));
  }
  else
  {
    bitplane_encode(val-1,l,WVTDECOMP_NUMBITPLANES(color,l));
    mzte_ac_encode_symbol(&ace,acm_sign[l],v_sign);
  }
}


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

  Arguments
  ---------
  Int y, Int x  - Coordinate of upper left hand corner of block.
  Int n - Number of 4 blocks in a side of the total block. 0 means do only 
   pixel at (x,y).
  Void (*pixelFunc)(Int, Int) - Function to call for pixel locations.
  
  Description
  -----------
  Call function pixelFunc(y,x) for all pixels (x,y) in block in band scan
  manner.

  Functions Called
  ----------------
  encodeBlocks recursively.

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

*************************************************************/
Void CVTCEncoder::encodeSQBlocks(Int y, Int x, Int n)
{
  /* Call the encoding function for the 4 block pixels */
  if (n == 0)
  {
    /* For checking scan-order : use 16x16 mono image
       for comparison with Figure 7-38 scan order table in 
       document.
    static Int i=4;

    noteStat("%d: y=%d, x=%d\n",i++, y,x);
    */

    encode_pixel_SQ(y,x);
  }
  else
  {
    Int k;

    --n;
    k = 1<<n;

    encodeSQBlocks(y,x,n);
    x += k;
    encodeSQBlocks(y,x,n);
    x -= k;
    y += k;
    encodeSQBlocks(y,x,n);
    x += k;
    encodeSQBlocks(y,x,n);
  }
}



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

  Arguments
  ---------
  Int y, Int x  - Coordinate of upper left hand corner of block.
  Int n - Number of 4 blocks in a side of the total block. 0 means do only 
   pixel at (x,y).
  Void (*pixelFunc)(Int, Int) - Function to call for pixel locations.
  
  Description
  -----------
  Call function pixelFunc(y,x) for all pixels (x,y) in block in band scan
  manner.

  Functions Called
  ----------------
  encodeBlocks recursively.

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

*************************************************************/
Void CVTCEncoder::encodeMQBlocks(Int y, Int x, Int n)
{
  /* Call the encoding function for the 4 block pixels */
  if (n == 0)
  {
    /* For checking scan-order : use 16x16 mono image
       for comparison with Figure 7-38 scan order table in 
       document.
    static Int i=4;

    noteStat("%d: y=%d, x=%d\n",i++, y,x);
    */

    encode_pixel_MQ(y,x);
  }
  else
  {
    Int k;

    --n;
    k = 1<<n;

    encodeMQBlocks(y,x,n);
    x += k;
    encodeMQBlocks(y,x,n);
    x -= k;
    y += k;
    encodeMQBlocks(y,x,n);
    x += k;
    encodeMQBlocks(y,x,n);
  }
}