me_umhexsmp.c

H.264编码实现

  // Search up_layer predictor for non 16x16 blocks
  if (blocktype > 1)
  {
    cand_x = pic_pix_x + (smpUMHEX_pred_MV_uplayer_X/4);
    cand_y = pic_pix_y + (smpUMHEX_pred_MV_uplayer_Y/4);
    SEARCH_ONE_PIXEL_HELPER
  }

  if(center_x != pic_pix_x || center_y != pic_pix_y)
  {
    cand_x = pic_pix_x;
    cand_y = pic_pix_y;
    SEARCH_ONE_PIXEL_HELPER

      iXMinNow = best_x;
    iYMinNow = best_y;
    // Local diamond search
    for (m = 0; m < 4; m++)
    {
      cand_x = iXMinNow + Diamond_X[m];
      cand_y = iYMinNow + Diamond_Y[m];
      SEARCH_ONE_PIXEL_HELPER
    }
  }

  // If the minimum cost is small enough, do a local search
  // and finish the search here
  if (min_mcost < (ConvergeThreshold>>block_type_shift_factor[blocktype]))
  {
    iXMinNow = best_x;
    iYMinNow = best_y;
    for (m = 0; m < 4; m++)
    {
      cand_x = iXMinNow + Diamond_X[m];
      cand_y = iYMinNow + Diamond_Y[m];
      SEARCH_ONE_PIXEL_HELPER
    }
    mv[0] = (short) (best_x - pic_pix_x);
    mv[1] = (short) (best_y - pic_pix_y);
    return min_mcost;
  }

  //second_step:  Extended Hexagon-based Search
  for(i = 0; i < search_range; i++)
  {
    iXMinNow = best_x;
    iYMinNow = best_y;
    for (m = 0; m < 6; m++)
    {
      cand_x = iXMinNow + Hexagon_X[m];
      cand_y = iYMinNow + Hexagon_Y[m];
      SEARCH_ONE_PIXEL_HELPER
    }
    // The minimum cost point happens in the center
    if (best_x == iXMinNow && best_y == iYMinNow)
    {
      break;
    }
  }

  //third_step: Small diamond search
  for(i = 0; i < search_range; i++)
  {
    iXMinNow = best_x;
    iYMinNow = best_y;
    for (m = 0; m < 4; m++)
    {
      cand_x = iXMinNow + Diamond_X[m];
      cand_y = iYMinNow + Diamond_Y[m];
      SEARCH_ONE_PIXEL_HELPER
    }

    // The minimum cost point happens in the center
    if (best_x == iXMinNow && best_y == iYMinNow)
    {
      break;
    }
  }

  mv[0] = (short) (best_x - pic_pix_x);
  mv[1] = (short) (best_y - pic_pix_y);

  for (j=(pic_pix_y>>2); j < (pic_pix_y>>2) + (blocksize_y>>2); j++)
  {
    for (i=(pic_pix_x>>2); i < (pic_pix_x>>2) + (blocksize_x>>2); i++)    
    {
      if(list == 0)
      {
        smpUMHEX_l0_cost[blocktype][j][i] = min_mcost;
      }
      else
      {
        smpUMHEX_l1_cost[blocktype][j][i] = min_mcost;
      }
    }
  }

  return min_mcost;
}

/*!
 ***********************************************************************
 * \brief
 *    Sub pixel block motion search enhanced
 ***********************************************************************
 */
int                                               //  ==> minimum motion cost after search
smpUMHEXFullSubPelBlockMotionSearch (imgpel*   orig_pic,      // <--  original pixel values for the AxB block
                                     short     ref,           // <--  reference frame (0... or -1 (backward))
                                     int       list,          // <--  reference picture list
                                     int       list_offset,
                                     int       pic_pix_x,     // <--  absolute x-coordinate of regarded AxB block
                                     int       pic_pix_y,     // <--  absolute y-coordinate of regarded AxB block
                                     int       blocktype,     // <--  block type (1-16x16 ... 7-4x4)
                                     short     pred_mv[2],    // <--  motion vector predictor (x|y) in sub-pel units
                                     short     mv[2],         // <--> in: search center (x|y) / out: motion vector (x|y) - in pel units
                                     int       search_pos2,   // <--  search positions for    half-pel search  (default: 9)
                                     int       search_pos4,   // <--  search positions for quarter-pel search  (default: 9)
                                     int       min_mcost,     // <--  minimum motion cost (cost for center or huge value)
                                     int       lambda_factor, // <--  lagrangian parameter for determining motion cost
                                     int       apply_weights
                                     )
{
  int   pos, best_pos, mcost;

  int   cand_mv_x, cand_mv_y;

  int   check_position0 = (!params->rdopt && img->type!=B_SLICE && ref==0 && blocktype==1 && mv[0]==0 && mv[1]==0);
  int   blocksize_x     = params->blc_size[blocktype][0];
  int   blocksize_y     = params->blc_size[blocktype][1];
  int   pic4_pix_x      = ((pic_pix_x + IMG_PAD_SIZE)<< 2);
  int   pic4_pix_y      = ((pic_pix_y + IMG_PAD_SIZE)<< 2);
  int   max_pos2        = ( !start_me_refinement_hp ? imax(1,search_pos2) : search_pos2);

  int   cmv_x, cmv_y;

  StorablePicture *ref_picture = listX[list+list_offset][ref];

  int max_pos_x4 = ((ref_picture->size_x - blocksize_x + 2*IMG_PAD_SIZE)<<2);
  int max_pos_y4 = ((ref_picture->size_y - blocksize_y + 2*IMG_PAD_SIZE)<<2);

  dist_method = Q_PEL + 3 * apply_weights;

  ref_pic_sub.luma = ref_picture->p_curr_img_sub;

  img_width  = ref_picture->size_x;
  img_height = ref_picture->size_y;
  width_pad  = ref_picture->size_x_pad;
  height_pad = ref_picture->size_y_pad;

  if (apply_weights)
  {
    weight_luma = wp_weight[list + list_offset][ref][0];
    offset_luma = wp_offset[list + list_offset][ref][0];
  }

  if (ChromaMEEnable)
  {
    ref_pic_sub.crcb[0] = ref_picture->imgUV_sub[0];
    ref_pic_sub.crcb[1] = ref_picture->imgUV_sub[1];
    width_pad_cr  = ref_picture->size_x_cr_pad;
    height_pad_cr = ref_picture->size_y_cr_pad;

    if (apply_weights)
    {
      weight_cr[0] = wp_weight[list + list_offset][ref][1];
      weight_cr[1] = wp_weight[list + list_offset][ref][2];
      offset_cr[0] = wp_offset[list + list_offset][ref][1];
      offset_cr[1] = wp_offset[list + list_offset][ref][2];
    }
  }

  /*********************************
   *****                       *****
   *****  HALF-PEL REFINEMENT  *****
   *****                       *****
   *********************************/

  //===== set function for getting pixel values =====
  if ((pic4_pix_x + mv[0] > 1) && (pic4_pix_x + mv[0] < max_pos_x4 - 1) &&
    (pic4_pix_y + mv[1] > 1) && (pic4_pix_y + mv[1] < max_pos_y4 - 1)   )
  {
    ref_access_method = FAST_ACCESS;
  }
  else
  {
    ref_access_method = UMV_ACCESS;
  }

  //===== loop over search positions =====
  for (best_pos = 0, pos = start_me_refinement_hp; pos < max_pos2; pos++)
  {
    cand_mv_x = mv[0] + (spiral_hpel_search_x[pos]);    // quarter-pel units
    cand_mv_y = mv[1] + (spiral_hpel_search_y[pos]);    // quarter-pel units

    //----- set motion vector cost -----
    mcost = MV_COST_SMP (lambda_factor, cand_mv_x, cand_mv_y, pred_mv[0], pred_mv[1]);

    if (mcost >= min_mcost) continue;

    cmv_x = cand_mv_x + pic4_pix_x;
    cmv_y = cand_mv_y + pic4_pix_y;

    mcost += computeUniPred[dist_method]( orig_pic, blocksize_y, blocksize_x, min_mcost - mcost, cmv_x, cmv_y);

    if (pos==0 && check_position0)
    {
      mcost -= WEIGHTED_COST (lambda_factor, 16);
    }

    if (mcost < min_mcost)
    {
      min_mcost = mcost;
      best_pos  = pos;
    }
    if (min_mcost < (SubPelThreshold3>>block_type_shift_factor[blocktype]))
    {
      break;
    }
  }

  if (best_pos)
  {
    mv[0] += (spiral_hpel_search_x [best_pos]);
    mv[1] += (spiral_hpel_search_y [best_pos]);
  }

  if ((mv[0] == 0) && (mv[1] == 0) && (pred_mv[0] == 0 && pred_mv[1] == 0) &&
    (min_mcost < (SubPelThreshold1>>block_type_shift_factor[blocktype])) )
  {
    best_pos = 0;
    return min_mcost;
  }

  if ( !start_me_refinement_qp )
    min_mcost = INT_MAX;

  /************************************
   *****                          *****
   *****  QUARTER-PEL REFINEMENT  *****
   *****                          *****
   ************************************/
  //===== set function for getting pixel values =====
  if ((pic4_pix_x + mv[0] > 0) && (pic4_pix_x + mv[0] < max_pos_x4) &&
    (pic4_pix_y + mv[1] > 0) && (pic4_pix_y + mv[1] < max_pos_y4)   )
  {
    ref_access_method = FAST_ACCESS;
  }
  else
  {
    ref_access_method = UMV_ACCESS;
  }

  //===== loop over search positions =====
  for (best_pos = 0, pos = start_me_refinement_qp; pos < search_pos4; pos++)
  {
    cand_mv_x = mv[0] + spiral_search_x[pos];    // quarter-pel units
    cand_mv_y = mv[1] + spiral_search_y[pos];    // quarter-pel units

    //----- set motion vector cost -----
    mcost = MV_COST_SMP (lambda_factor, cand_mv_x, cand_mv_y, pred_mv[0], pred_mv[1]);

    if (mcost >= min_mcost) continue;

    cmv_x = cand_mv_x + pic4_pix_x;
    cmv_y = cand_mv_y + pic4_pix_y;

    mcost += computeUniPred[dist_method]( orig_pic, blocksize_y, blocksize_x, min_mcost - mcost, cmv_x, cmv_y);

    if (mcost < min_mcost)
    {
      min_mcost = mcost;
      best_pos  = pos;
    }
    if (min_mcost < (SubPelThreshold3>>block_type_shift_factor[blocktype]))
    {
      break;
    }
  }

  if (best_pos)
  {
    mv[0] += spiral_search_x [best_pos];
    mv[1] += spiral_search_y [best_pos];
  }

  //===== return minimum motion cost =====
  return min_mcost;
}


/*!
 ************************************************************************
 * \brief
 *    Fast sub pixel block motion estimation
 ************************************************************************
 */
int                                     //  ==> minimum motion cost after search
smpUMHEXSubPelBlockMotionSearch  (
                                  imgpel* orig_pic,        // <--  original pixel values for the AxB block
                                  short     ref,           // <--  reference frame (0... or -1 (backward))
                                  int       list,          // <--  reference picture list
                                  int       list_offset,   // <--  MBAFF list offset
                                  int       pic_pix_x,     // <--  absolute x-coordinate of regarded AxB block
                                  int       pic_pix_y,     // <--  absolute y-coordinate of regarded AxB block
                                  int       blocktype,     // <--  block type (1-16x16 ... 7-4x4)
                                  short     pred_mv[2],    // <--  motion vector predictor (x|y) in sub-pel units
                                  short     mv[2],         // <--> in: search center (x|y) / out: MV (x|y) - in pel units
                                  int       search_pos2,   // <--  search positions for    half-pel search  (default: 9)
                                  int       search_pos4,   // <--  search positions for quarter-pel search  (default: 9)
                                  int       min_mcost,     // <--  minimum motion cost (cost for center or huge value)
                                  int       lambda_factor, // <--  lagrangian parameter for determining motion cost
                                  int       apply_weights
                                  )
{
  int   mcost;
  int   cand_mv_x, cand_mv_y;

  StorablePicture *ref_picture = listX[list+list_offset][ref];

  short mv_shift        = 0;
  short blocksize_x     = (short) params->blc_size[blocktype][0];