mpg2encdlg.cpp

mpeg2视频编码

        }
      }
      else
      {
        /* No MC */
        var = v0;
        mbi->mb_type = 0;
        mbi->motion_type = MC_FIELD;
        mbi->MV[0][0][0] = 0;
        mbi->MV[0][0][1] = 0;
        mbi->mv_field_sel[0][0] = (pict_struct==BOTTOM_FIELD);
      }
    }
  }
  else /* if (pict_type==B_TYPE) */
  {
    /* forward prediction */
    field_estimate(oldorg,oldref,oldorg+width,oldref+width,mb,
                   i,j,sxf,syf,0,
                   &iminf,&jminf,&imin8uf,&jmin8uf,&imin8lf,&jmin8lf,
                   &dmcfieldf,&dmc8f,&self,&sel8uf,&sel8lf,&imins,&jmins,&ds);

    /* backward prediction */
    field_estimate(neworg,newref,neworg+width,newref+width,mb,
                   i,j,sxb,syb,0,
                   &iminr,&jminr,&imin8ur,&jmin8ur,&imin8lr,&jmin8lr,
                   &dmcfieldr,&dmc8r,&selr,&sel8ur,&sel8lr,&imins,&jmins,&ds);

    /* calculate distances for bidirectional prediction */
    /* field */
    dmcfieldi = bdist1(oldref + (self?width:0) + (iminf>>1) + w2*(jminf>>1),
                       newref + (selr?width:0) + (iminr>>1) + w2*(jminr>>1),
                       mb,w2,iminf&1,jminf&1,iminr&1,jminr&1,16);

    /* 16x8 upper half block */
    dmc8i = bdist1(oldref + (sel8uf?width:0) + (imin8uf>>1) + w2*(jmin8uf>>1),
                   newref + (sel8ur?width:0) + (imin8ur>>1) + w2*(jmin8ur>>1),
                   mb,w2,imin8uf&1,jmin8uf&1,imin8ur&1,jmin8ur&1,8);

    /* 16x8 lower half block */
    dmc8i+= bdist1(oldref + (sel8lf?width:0) + (imin8lf>>1) + w2*(jmin8lf>>1),
                   newref + (sel8lr?width:0) + (imin8lr>>1) + w2*(jmin8lr>>1),
                   mb+8*w2,w2,imin8lf&1,jmin8lf&1,imin8lr&1,jmin8lr&1,8);

    /* select prediction type of minimum distance */
    if (dmcfieldi<dmc8i && dmcfieldi<dmcfieldf && dmcfieldi<dmc8f
        && dmcfieldi<dmcfieldr && dmcfieldi<dmc8r)
    {
      /* field, interpolated */
      mbi->mb_type = MB_FORWARD|MB_BACKWARD;
      mbi->motion_type = MC_FIELD;
      vmc = bdist2(oldref + (self?width:0) + (iminf>>1) + w2*(jminf>>1),
                   newref + (selr?width:0) + (iminr>>1) + w2*(jminr>>1),
                   mb,w2,iminf&1,jminf&1,iminr&1,jminr&1,16);
    }
    else if (dmc8i<dmcfieldf && dmc8i<dmc8f
             && dmc8i<dmcfieldr && dmc8i<dmc8r)
    {
      /* 16x8, interpolated */
      mbi->mb_type = MB_FORWARD|MB_BACKWARD;
      mbi->motion_type = MC_16X8;

      /* upper half block */
      vmc = bdist2(oldref + (sel8uf?width:0) + (imin8uf>>1) + w2*(jmin8uf>>1),
                   newref + (sel8ur?width:0) + (imin8ur>>1) + w2*(jmin8ur>>1),
                   mb,w2,imin8uf&1,jmin8uf&1,imin8ur&1,jmin8ur&1,8);

      /* lower half block */
      vmc+= bdist2(oldref + (sel8lf?width:0) + (imin8lf>>1) + w2*(jmin8lf>>1),
                   newref + (sel8lr?width:0) + (imin8lr>>1) + w2*(jmin8lr>>1),
                   mb+8*w2,w2,imin8lf&1,jmin8lf&1,imin8lr&1,jmin8lr&1,8);
    }
    else if (dmcfieldf<dmc8f && dmcfieldf<dmcfieldr && dmcfieldf<dmc8r)
    {
      /* field, forward */
      mbi->mb_type = MB_FORWARD;
      mbi->motion_type = MC_FIELD;
      vmc = dist2(oldref + (self?width:0) + (iminf>>1) + w2*(jminf>>1),
                  mb,w2,iminf&1,jminf&1,16);
    }
    else if (dmc8f<dmcfieldr && dmc8f<dmc8r)
    {
      /* 16x8, forward */
      mbi->mb_type = MB_FORWARD;
      mbi->motion_type = MC_16X8;

      /* upper half block */
      vmc = dist2(oldref + (sel8uf?width:0) + (imin8uf>>1) + w2*(jmin8uf>>1),
                  mb,w2,imin8uf&1,jmin8uf&1,8);

      /* lower half block */
      vmc+= dist2(oldref + (sel8lf?width:0) + (imin8lf>>1) + w2*(jmin8lf>>1),
                  mb+8*w2,w2,imin8lf&1,jmin8lf&1,8);
    }
    else if (dmcfieldr<dmc8r)
    {
      /* field, backward */
      mbi->mb_type = MB_BACKWARD;
      mbi->motion_type = MC_FIELD;
      vmc = dist2(newref + (selr?width:0) + (iminr>>1) + w2*(jminr>>1),
                  mb,w2,iminr&1,jminr&1,16);
    }
    else
    {
      /* 16x8, backward */
      mbi->mb_type = MB_BACKWARD;
      mbi->motion_type = MC_16X8;

      /* upper half block */
      vmc = dist2(newref + (sel8ur?width:0) + (imin8ur>>1) + w2*(jmin8ur>>1),
                  mb,w2,imin8ur&1,jmin8ur&1,8);

      /* lower half block */
      vmc+= dist2(newref + (sel8lr?width:0) + (imin8lr>>1) + w2*(jmin8lr>>1),
                  mb+8*w2,w2,imin8lr&1,jmin8lr&1,8);
    }

    /* select between intra and non-intra coding */
    if (vmc>var && vmc>=9*256)
      mbi->mb_type = MB_INTRA;
    else
    {
      var = vmc;
      if (mbi->motion_type==MC_FIELD)
      {
        /* forward */
        mbi->MV[0][0][0] = iminf - (i<<1);
        mbi->MV[0][0][1] = jminf - (j<<1);
        mbi->mv_field_sel[0][0] = self;
        /* backward */
        mbi->MV[0][1][0] = iminr - (i<<1);
        mbi->MV[0][1][1] = jminr - (j<<1);
        mbi->mv_field_sel[0][1] = selr;
      }
      else /* MC_16X8 */
      {
        /* forward */
        mbi->MV[0][0][0] = imin8uf - (i<<1);
        mbi->MV[0][0][1] = jmin8uf - (j<<1);
        mbi->mv_field_sel[0][0] = sel8uf;
        mbi->MV[1][0][0] = imin8lf - (i<<1);
        mbi->MV[1][0][1] = jmin8lf - ((j+8)<<1);
        mbi->mv_field_sel[1][0] = sel8lf;
        /* backward */
        mbi->MV[0][1][0] = imin8ur - (i<<1);
        mbi->MV[0][1][1] = jmin8ur - (j<<1);
        mbi->mv_field_sel[0][1] = sel8ur;
        mbi->MV[1][1][0] = imin8lr - (i<<1);
        mbi->MV[1][1][1] = jmin8lr - ((j+8)<<1);
        mbi->mv_field_sel[1][1] = sel8lr;
      }
    }
  }

  mbi->var = var;
}
/////////////////////////////////////////////////////////////////////////////////
void motion_estimation(unsigned char *oldorg,unsigned char *neworg,unsigned char *oldref,unsigned char *newref,
					   unsigned char *cur,unsigned char *curref,
					   int sxf,int syf,int sxb,int syb,
					   struct mbinfo *mbi,
					   int secondfield,int ipflag)
{
  int i, j;

    /* 对所有的宏块进行循环操作 */
  for (j=0; j<height2; j+=16)
  {
    for (i=0; i<width; i+=16)
    {
		 /*根据图像结构的类型来判断是进行帧预测还是场预测*/     
      if (pict_struct==FRAME_PICTURE)
        frame_ME(oldorg,neworg,oldref,newref,cur,i,j,sxf,syf,sxb,syb,mbi);
      else
        field_ME(oldorg,neworg,oldref,newref,cur,curref,i,j,sxf,syf,sxb,syb,
          mbi,secondfield,ipflag);
      mbi++;
    }

    if (!quiet)
    {
      putc('.',stderr);
      fflush(stderr);
    }
  }
  if (!quiet)
    putc('\n',stderr);
}
//////////////////////////////////////////////////////////////////////////////////////
static void calc_DMV(int DMV[][2],int *dmvector,int mvx, int mvy)
{
  if (pict_struct==FRAME_PICTURE)
  {
    if (topfirst)
    {
      /* vector for prediction of top field from bottom field */
      DMV[0][0] = ((mvx  +(mvx>0))>>1) + dmvector[0];
      DMV[0][1] = ((mvy  +(mvy>0))>>1) + dmvector[1] - 1;

      /* vector for prediction of bottom field from top field */
      DMV[1][0] = ((3*mvx+(mvx>0))>>1) + dmvector[0];
      DMV[1][1] = ((3*mvy+(mvy>0))>>1) + dmvector[1] + 1;
    }
    else
    {
      /* vector for prediction of top field from bottom field */
      DMV[0][0] = ((3*mvx+(mvx>0))>>1) + dmvector[0];
      DMV[0][1] = ((3*mvy+(mvy>0))>>1) + dmvector[1] - 1;

      /* vector for prediction of bottom field from top field */
      DMV[1][0] = ((mvx  +(mvx>0))>>1) + dmvector[0];
      DMV[1][1] = ((mvy  +(mvy>0))>>1) + dmvector[1] + 1;
    }
  }
  else
  {
    /* vector for prediction from field of opposite 'parity' */
    DMV[0][0] = ((mvx+(mvx>0))>>1) + dmvector[0];
    DMV[0][1] = ((mvy+(mvy>0))>>1) + dmvector[1];

    /* correct for vertical field shift */
    if (pict_struct==TOP_FIELD)
      DMV[0][1]--;
    else
      DMV[0][1]++;
  }
}
////////////////////////////////////////////////////////////////////
static void clearblock(unsigned char *cur[],int i0, int j0)
{
  int i, j, w, h;
  unsigned char *p;

  p = cur[0] + ((pict_struct==BOTTOM_FIELD) ? width : 0) + i0 + width2*j0;

  for (j=0; j<16; j++)
  {
    for (i=0; i<16; i++)
      p[i] = 128;
    p+= width2;
  }

  w = h = 16;

  if (chroma_format!=CHROMA444)
  {
    i0>>=1; w>>=1;
  }

  if (chroma_format==CHROMA420)
  {
    j0>>=1; h>>=1;
  }

  p = cur[1] + ((pict_struct==BOTTOM_FIELD) ? chrom_width : 0) + i0
             + chrom_width2*j0;

  for (j=0; j<h; j++)
  {
    for (i=0; i<w; i++)
      p[i] = 128;
    p+= chrom_width2;
  }

  p = cur[2] + ((pict_struct==BOTTOM_FIELD) ? chrom_width : 0) + i0
             + chrom_width2*j0;

  for (j=0; j<h; j++)
  {
    for (i=0; i<w; i++)
      p[i] = 128;
    p+= chrom_width2;
  }
}
/////////////////////////////////////////////////////////////
/* 低等级预测
 * src:     源帧(Y,U,V)
 * dst:     目标帧(Y,U,V)
 *
 * lx:      相邻像素的垂直距离
 * w,h:     块的宽度和高度
 * x,y:     目标块的坐标
 * dx,dy:   半像素运动向量
 * addflag: 存储或加预测*/
static void pred_comp(unsigned char *src,unsigned char *dst,int lx,int w,
					  int h,int x, int y,int dx,int dy,int addflag)
{
  int xint, xh, yint, yh;
  int i, j;
  unsigned char *s, *d;

  /* half pel scaling */
  xint = dx>>1; /* integer part */
  xh = dx & 1;  /* half pel flag */
  yint = dy>>1;
  yh = dy & 1;

  /* origins */
  s = src + lx*(y+yint) + (x+xint); /* motion vector */
  d = dst + lx*y + x;

  if (!xh && !yh)
    if (addflag)
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (unsigned int)(d[i]+s[i]+1)>>1;
        s+= lx;
        d+= lx;
      }
    else
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = s[i];
        s+= lx;
        d+= lx;
      }
  else if (!xh && yh)
    if (addflag)
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (d[i] + ((unsigned int)(s[i]+s[i+lx]+1)>>1)+1)>>1;
        s+= lx;
        d+= lx;
      }
    else
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (unsigned int)(s[i]+s[i+lx]+1)>>1;
        s+= lx;
        d+= lx;
      }
  else if (xh && !yh)
    if (addflag)
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (d[i] + ((unsigned int)(s[i]+s[i+1]+1)>>1)+1)>>1;
        s+= lx;
        d+= lx;
      }
    else
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (unsigned int)(s[i]+s[i+1]+1)>>1;
        s+= lx;
        d+= lx;
      }
  else /* if (xh && yh) */
    if (addflag)
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (d[i] + ((unsigned int)(s[i]+s[i+1]+s[i+lx]+s[i+lx+1]+2)>>2)+1)>>1;
        s+= lx;
        d+= lx;
      }
    else
      for (j=0; j<h; j++)
      {
        for (i=0; i<w; i++)
          d[i] = (unsigned int)(s[i]+s[i+1]+s[i+lx]+s[i+lx+1]+2)>>2;
        s+= lx;
        d+= lx;
      }
}
/////////////////////////////////////////////
/* 预测矩形块
 * src:     源帧(Y,U,V)
 * sfield:  源场选择(0: 帧或上半场, 1: 下半场)
 * dst:     目标帧(Y,U,V)
 * dfield:  目标场选择
 *
 * 下面的数值是亮度图像的参数
 * lx:      相邻像素的垂直距离
 * w,h:     块的宽度和高度
 * x,y:     目标块的坐标
 * dx,dy:   半像素运动向量
 * addflag: 存储或加预测*//* 预测矩形块
 * src:     源帧(Y,U,V)
 * sfield:  源场选择(0: 帧或上半场, 1: 下半场)
 * dst:     目标帧(Y,U,V)
 * dfield:  目标场选择
 *
 * 下面的数值是亮度图像的参数
 * lx:      相邻像素的垂直距离
 * w,h:     块的宽度和高度
 * x,y:     目标块的坐标
 * dx,dy:   半像素运动向量
 * addflag: 存储或加预测*/
static void pred(unsigned char *src[],int sfield,unsigned char *dst[],int dfield,
				 int lx,int w, int h,int x, int y,int dx, int dy,int addflag)
{
  int cc;

  for (cc=0; cc<3; cc++)
  {
    if (cc==1)
    {
      /* scale for color components */
      if (chroma_format==CHROMA420)
      {
        /* vertical */
        h >>= 1; y >>= 1; dy /= 2;
      }
      if (chroma_format!=CHROMA444)
      {
        /* horizontal */
        w >>= 1; x >>= 1; dx /= 2;
        lx >>= 1;
      }
    }
    pred_comp(src[cc]+(sfield?lx>>1:0),dst[cc]+(dfield?lx>>1:0),
      lx,w,h,x,y,dx,dy,addflag);
  }
}
///////////////////////////////////////////////
/* 为一个宏块形成预测
    oldref: 用来进行前向预测的参考帧
	newref: 用来进行后向预测的参考帧
	cur: 目标帧（即当前要预测的帧）
	lx: 帧的宽度（与全局变量"width"一致）
	bx、by: 要被预测的宏块的图像坐标（可以是场，也可以是帧）
	pict_type: 图像类型，就是I、P或B
	pict_struct: 图像的结构，就是帧图像（FRAME_PICTURE），上部分的场图像
	（TOP_FIELD）和下部分的场图像（BOTTOM_FIELD）
	
	mb_type: 宏块类型，可以是前向（MB_FORWARD）,也可以是后向（MB_BACKWARD）
	或是帧内（MB_INTRA）宏块
	
	  motion_type: 运动类型，主要用值MC_FRAME, MC_FIELD、MC_16X8、MC_DMV表示
	secondfield: 预测帧的第二个场图像
	PMV[2][2][2]: 运动向量（以半像素图像坐标为单位）
	mv_field_sel[2][2]: 垂直运动场选择（针对场预测）
	dmvector: 差分运动向量*/
static void predict_mb(unsigned char *oldref[],unsigned char *newref[],unsigned char *cur[],
					   int lx,int bx,int by,int pict_type,int pict_struct,int mb_type,
					   int motion_type,int se