macroblock.c

H.264视频编码器(ITU的264编码参考软件)

          bx = ((b8&1)<<1) + i;
          by = (b8&2)      + j;

          getLuma4x4Neighbour(img->current_mb_nr, bx, by, -1,  0, &left_block);
          getLuma4x4Neighbour(img->current_mb_nr, bx, by,  0, -1, &top_block);
          
          //get from array and decode
          bi = img->block_x + bx;
          bj = img->block_y + by;

          if (active_pps->constrained_intra_pred_flag)
          {
            left_block.available = left_block.available ? img->intra_block[left_block.mb_addr] : 0;
            top_block.available  = top_block.available  ? img->intra_block[top_block.mb_addr]  : 0;
          }

          // !! KS: not sure if the follwing is still correct...
          ts=ls=0;   // Check to see if the neighboring block is SI
          if (IS_OLDINTRA(currMB) && img->type == SI_SLICE)           // need support for MBINTLC1
          {
            if (left_block.available)
              if (img->siblock [left_block.pos_x][left_block.pos_y])
                ls=1;

            if (top_block.available)
              if (img->siblock [top_block.pos_x][top_block.pos_y])
                ts=1;
          }

          upIntraPredMode            = (top_block.available  &&(ts == 0)) ? img->ipredmode[top_block.pos_x ][top_block.pos_y ] : -1;
          leftIntraPredMode          = (left_block.available &&(ls == 0)) ? img->ipredmode[left_block.pos_x][left_block.pos_y] : -1;

          mostProbableIntraPredMode  = (upIntraPredMode < 0 || leftIntraPredMode < 0) ? DC_PRED : upIntraPredMode < leftIntraPredMode ? upIntraPredMode : leftIntraPredMode;

          dec = (currSE.value1 == -1) ? mostProbableIntraPredMode : currSE.value1 + (currSE.value1 >= mostProbableIntraPredMode);

          //set
          for(jj=0;jj<(bs_y>>2);jj++)   //loop 4x4s in the subblock for 8x8 prediction setting
            for(ii=0;ii<(bs_x>>2);ii++)
              img->ipredmode[bi+ii][bj+jj]=dec;
        }
    }
  }

  if (IntraChromaPredModeFlag && img->yuv_format != YUV400)
  {
    currSE.type = SE_INTRAPREDMODE;
    TRACE_STRING("intra_chroma_pred_mode");
    dP = &(currSlice->partArr[partMap[currSE.type]]);

    if (active_pps->entropy_coding_mode_flag == UVLC || dP->bitstream->ei_flag) currSE.mapping = linfo_ue;
    else                                                    currSE.reading = readCIPredMode_CABAC;

    dP->readSyntaxElement(&currSE,img,inp,dP);
    currMB->c_ipred_mode = currSE.value1;

    if (currMB->c_ipred_mode < DC_PRED_8 || currMB->c_ipred_mode > PLANE_8)
    {
      error("illegal chroma intra pred mode!\n", 600);
    }
  }
}

/*!
 ************************************************************************
 * \brief
 *    Set motion vector predictor
 ************************************************************************
 */
static void SetMotionVectorPredictor (struct img_par  *img,
                                      int             *pmv_x,
                                      int             *pmv_y,
                                      int             ref_frame,
                                      int             list,
                                      int             ***refPic,
                                      int             ****tmp_mv,
                                      int             block_x,
                                      int             block_y,
                                      int             blockshape_x,
                                      int             blockshape_y)
{
  int mb_x                 = BLOCK_SIZE*block_x;
  int mb_y                 = BLOCK_SIZE*block_y;
  int mb_nr                = img->current_mb_nr;

  int mv_a, mv_b, mv_c, pred_vec=0;
  int mvPredType, rFrameL, rFrameU, rFrameUR;
  int hv;


  PixelPos block_a, block_b, block_c, block_d;

  getLuma4x4Neighbour(mb_nr, block_x, block_y,           -1,  0, &block_a);
  getLuma4x4Neighbour(mb_nr, block_x, block_y,            0, -1, &block_b);
  getLuma4x4Neighbour(mb_nr, block_x, block_y, blockshape_x, -1, &block_c);
  getLuma4x4Neighbour(mb_nr, block_x, block_y,           -1, -1, &block_d);

  if (mb_y > 0)
  {
    if (mb_x < 8)  // first column of 8x8 blocks
    {
      if (mb_y==8)
      {
        if (blockshape_x == 16)      block_c.available  = 0;
        else                         block_c.available &= 1;
      }
      else
      {
        if (mb_x+blockshape_x != 8)  block_c.available &= 1;
        else                         block_c.available  = 0;
      }
    }
    else
    {
      if (mb_x+blockshape_x != 16)   block_c.available &= 1;
      else                           block_c.available  = 0;
    }
  }

  if (!block_c.available)
  {
    block_c=block_d;
  }

  mvPredType = MVPRED_MEDIAN;

  if (!img->MbaffFrameFlag)
  {
    rFrameL    = block_a.available    ? refPic[list][block_a.pos_x][block_a.pos_y] : -1;
    rFrameU    = block_b.available    ? refPic[list][block_b.pos_x][block_b.pos_y] : -1;
    rFrameUR   = block_c.available    ? refPic[list][block_c.pos_x][block_c.pos_y] : -1;
  }
  else
  {
    if (img->mb_data[img->current_mb_nr].mb_field)
    {
      rFrameL    = block_a.available    ? 
        img->mb_data[block_a.mb_addr].mb_field ? 
        refPic[list][block_a.pos_x][block_a.pos_y]:
        refPic[list][block_a.pos_x][block_a.pos_y] * 2: 
        -1;
      rFrameU    = block_b.available    ? 
        img->mb_data[block_b.mb_addr].mb_field ? 
        refPic[list][block_b.pos_x][block_b.pos_y]:
        refPic[list][block_b.pos_x][block_b.pos_y] * 2: 
        -1;
      rFrameUR    = block_c.available    ? 
        img->mb_data[block_c.mb_addr].mb_field ? 
        refPic[list][block_c.pos_x][block_c.pos_y]:
        refPic[list][block_c.pos_x][block_c.pos_y] * 2: 
        -1;
    }
    else
    {
      rFrameL    = block_a.available    ? 
        img->mb_data[block_a.mb_addr].mb_field ? 
        refPic[list][block_a.pos_x][block_a.pos_y] >>1:
        refPic[list][block_a.pos_x][block_a.pos_y] : 
        -1;
      rFrameU    = block_b.available    ? 
        img->mb_data[block_b.mb_addr].mb_field ? 
        refPic[list][block_b.pos_x][block_b.pos_y] >>1:
        refPic[list][block_b.pos_x][block_b.pos_y] : 
        -1;
      rFrameUR    = block_c.available    ? 
        img->mb_data[block_c.mb_addr].mb_field ? 
        refPic[list][block_c.pos_x][block_c.pos_y] >>1:
        refPic[list][block_c.pos_x][block_c.pos_y] : 
        -1;
    }
  }


  /* Prediction if only one of the neighbors uses the reference frame
   * we are checking
   */
  if(rFrameL == ref_frame && rFrameU != ref_frame && rFrameUR != ref_frame)       mvPredType = MVPRED_L;
  else if(rFrameL != ref_frame && rFrameU == ref_frame && rFrameUR != ref_frame)  mvPredType = MVPRED_U;
  else if(rFrameL != ref_frame && rFrameU != ref_frame && rFrameUR == ref_frame)  mvPredType = MVPRED_UR;
  // Directional predictions 
  if(blockshape_x == 8 && blockshape_y == 16)
  {
    if(mb_x == 0)
    {
      if(rFrameL == ref_frame)
        mvPredType = MVPRED_L;
    }
    else
    {
      if( rFrameUR == ref_frame)
        mvPredType = MVPRED_UR;
    }
  }
  else if(blockshape_x == 16 && blockshape_y == 8)
  {
    if(mb_y == 0)
    {
      if(rFrameU == ref_frame)
        mvPredType = MVPRED_U;
    }
    else
    {
      if(rFrameL == ref_frame)
        mvPredType = MVPRED_L;
    }
  }

  for (hv=0; hv < 2; hv++)
  {
    if (!img->MbaffFrameFlag || hv==0)
    {
      mv_a = block_a.available  ? tmp_mv[list][block_a.pos_x][block_a.pos_y][hv] : 0;
      mv_b = block_b.available  ? tmp_mv[list][block_b.pos_x][block_b.pos_y][hv] : 0;
      mv_c = block_c.available  ? tmp_mv[list][block_c.pos_x][block_c.pos_y][hv] : 0;
    }
    else
    {
      if (img->mb_data[img->current_mb_nr].mb_field)
      {
        mv_a = block_a.available  ? img->mb_data[block_a.mb_addr].mb_field?
          tmp_mv[list][block_a.pos_x][block_a.pos_y][hv]:
          tmp_mv[list][block_a.pos_x][block_a.pos_y][hv] / 2: 
          0;
        mv_b = block_b.available  ? img->mb_data[block_b.mb_addr].mb_field?
          tmp_mv[list][block_b.pos_x][block_b.pos_y][hv]:
          tmp_mv[list][block_b.pos_x][block_b.pos_y][hv] / 2: 
          0;
        mv_c = block_c.available  ? img->mb_data[block_c.mb_addr].mb_field?
          tmp_mv[list][block_c.pos_x][block_c.pos_y][hv]:
          tmp_mv[list][block_c.pos_x][block_c.pos_y][hv] / 2: 
          0;
      }
      else
      {
        mv_a = block_a.available  ? img->mb_data[block_a.mb_addr].mb_field?
          tmp_mv[list][block_a.pos_x][block_a.pos_y][hv] * 2:
          tmp_mv[list][block_a.pos_x][block_a.pos_y][hv]: 
          0;
        mv_b = block_b.available  ? img->mb_data[block_b.mb_addr].mb_field?
          tmp_mv[list][block_b.pos_x][block_b.pos_y][hv] * 2:
          tmp_mv[list][block_b.pos_x][block_b.pos_y][hv]: 
          0;
        mv_c = block_c.available  ? img->mb_data[block_c.mb_addr].mb_field?
          tmp_mv[list][block_c.pos_x][block_c.pos_y][hv] * 2:
          tmp_mv[list][block_c.pos_x][block_c.pos_y][hv]: 
          0;
      }
    }


    switch (mvPredType)
    {
    case MVPRED_MEDIAN:
      if(!(block_b.available || block_c.available))
        pred_vec = mv_a;
      else
        pred_vec = mv_a+mv_b+mv_c-min(mv_a,min(mv_b,mv_c))-max(mv_a,max(mv_b,mv_c));
      break;
    case MVPRED_L:
      pred_vec = mv_a;
      break;
    case MVPRED_U:
      pred_vec = mv_b;
      break;
    case MVPRED_UR:
      pred_vec = mv_c;
      break;
    default:
      break;
    }

    if (hv==0)  *pmv_x = pred_vec;
    else        *pmv_y = pred_vec;

  }
}


/*!
 ************************************************************************
 * \brief
 *    Set context for reference frames
 ************************************************************************
 */
int
BType2CtxRef (int btype)
{
  if (btype<4)  return 0;
  else          return 1;
}

/*!
 ************************************************************************
 * \brief
 *    Read motion info
 ************************************************************************
 */
void readMotionInfoFromNAL (struct img_par *img, struct inp_par *inp)
{
  int i,j,k;
  int step_h,step_v;
  int curr_mvd;
  Macroblock *currMB  = &img->mb_data[img->current_mb_nr];
  SyntaxElement currSE;
  Slice *currSlice    = img->currentSlice;
  DataPartition *dP;
  int *partMap        = assignSE2partition[currSlice->dp_mode];
  int bframe          = (img->type==B_SLICE);
  int partmode        = (IS_P8x8(currMB)?4:currMB->mb_type);
  int step_h0         = BLOCK_STEP [partmode][0];
  int step_v0         = BLOCK_STEP [partmode][1];

  int mv_mode, i0, j0, refframe;
  int pmv[2];
  int j4, i4, ii,jj;
  int vec;

  int mv_scale = 0;

  int flag_mode;

  int list_offset = ((img->MbaffFrameFlag)&&(currMB->mb_field))? img->current_mb_nr%2 ? 4 : 2 : 0;

  byte **    moving_block;
  int ****   co_located_mv;
  int ***    co_located_ref_idx;
  int64 ***    co_located_ref_id;

  if ((img->MbaffFrameFlag)&&(currMB->mb_field))
  {
    if(img->current_mb_nr%2)
    {
      moving_block = Co_located->bottom_moving_block;
      co_located_mv = Co_located->bottom_mv;
      co_located_ref_idx = Co_located->bottom_ref_idx;
      co_located_ref_id = Co_located->bottom_ref_pic_id;
    }
    else
    {
      moving_block = Co_located->top_moving_block;
      co_located_mv = Co_located->top_mv;
      co_located_ref_idx = Co_located->top_ref_idx;
      co_located_ref_id = Co_located->top_ref_pic_id;
    }
  }
  else
  {
    moving_block = Co_located->moving_block;
    co_located_mv = Co_located->mv;
    co_located_ref_idx = Co_located->ref_idx;
    co_located_ref_id = Co_located->ref_pic_id;
  }

  if (bframe && IS_P8x8 (currMB))
  {
    if (img->direct_spatial_mv_pred_flag)
    {
      int imgblock_y= ((img->MbaffFrameFlag)&&(currMB->mb_field))? (img->current_mb_nr%2) ? (img->block_y-4)/2:img->block_y/2: img->block_y;
      int fw_rFrameL, fw_rFrameU, fw_rFrameUL, fw_rFrameUR;
      int bw_rFrameL, bw_rFrameU, bw_rFrameUL, bw_rFrameUR;
      
      PixelPos mb_left, mb_up, mb_upleft, mb_upright;
      
      int fw_rFrame,bw_rFrame;
      int pmvfw[2]={0,0},pmvbw[2]={0,0};
      
      
      getLuma4x4Neighbour(img->current_mb_nr, 0, 0, -1,  0, &mb_left);
      getLuma4x4Neighbour(img->current_mb_nr, 0, 0,  0, -1, &mb_up);
      getLuma4x4Neighbour(img->current_mb_nr, 0, 0, 16, -1, &mb_upright);
      getLuma4x4Neighbour(img->current_mb_nr, 0, 0, -1, -1, &mb_upleft);

      if (!img->MbaffFrameFlag)
      {
        fw_rFrameL = mb_left.available ? dec_picture->ref_idx[LIST_0][mb_left.pos_x][mb_left.pos_y] : -1;
        fw_rFrameU = mb_up.available ? dec_picture->ref_idx[LIST_0][mb_up.pos_x][mb_up.pos_y] : -1;
        fw_rFrameUL = mb_upleft.available ? dec_picture->ref_idx[LIST_0][mb_upleft.pos_x][mb_upleft.pos_y] : -1;
        fw_rFrameUR = mb_upright.available ? dec_picture->ref_idx[LIST_0][mb_upright.pos_x][mb_upright.pos_y] : fw_rFrameUL;      
        
        bw_rFrameL = mb_left.available ? dec_picture->ref_idx[LIST_1][mb_left.pos_x][mb_left.pos_y] : -1;
        bw_rFrameU = mb_up.available ? dec_picture->ref_idx[LIST_1][mb_up.pos_x][mb_up.pos_y] : -1;
        bw_rFrameUL = mb_upleft.available ? dec_picture->ref_idx[LIST_1][mb_upleft.pos_x][mb_upleft.pos_y] : -1;
        bw_rFrameUR = mb_upright.available ? dec_picture->ref_idx[LIST_1][mb_upright.pos_x][mb_upright.pos_y] : bw_rFrameUL;      
      }
      else
      {
        if (img->mb_data[img->current_mb_nr].mb_field)
        {