me_fullsearch.c

H.264编码实现

/*!
*************************************************************************************
* \file me_fullsearch.c
*
* \brief
*    Motion Estimation using Fullsearch
*
* \author
*    Main contributors (see contributors.h for copyright, address and affiliation details)
*      - Alexis Michael Tourapis <[e-mail]>
*      - Athanasios Leontaris    <[e-mail]>
*
*************************************************************************************
*/

// Includes
#include "contributors.h"
#include <limits.h>

#include "global.h"
#include "image.h"
#include "memalloc.h"
#include "mb_access.h"
#include "refbuf.h"

#include "me_distortion.h"
#include "me_fullsearch.h"
#include "mv-search.h"

// Define Global Parameters
extern short*  spiral_search_x;
extern short*  spiral_search_y;
extern short*  spiral_hpel_search_x;
extern short*  spiral_hpel_search_y;

// Functions
/*!
 ***********************************************************************
 * \brief
 *    Full pixel block motion search
 ***********************************************************************
 */
int                                                //  ==> minimum motion cost after search
FullPelBlockMotionSearch (Macroblock *currMB ,     // <--  current Macroblock
                          imgpel*   orig_pic,      // <--  original pixel values for the AxB block
                          short     ref,           // <--  reference frame (0... or -1 (backward))
                          int       list,          // <--  current list
                          int       list_offset,   // <--  MBAFF list offset
                          char   ***refPic,        // <--  reference array
                          short ****tmp_mv,        // <--  mv array
                          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) in sub-pel units
                          short     mv[2],         // <--> in: search center (x) / out: motion vector (x) - in pel units
                          int       search_range,  // <--  1-d search range in pel units
                          int       min_mcost,     // <--  minimum motion cost (cost for center or huge value)
                          int       lambda_factor, // <--  lagrangian parameter for determining motion cost
                          int       apply_weights) // <--  use weight based ME
{
  int   pos, cand_x, cand_y, mcost;

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

  int   best_pos      = 0;                                        // position with minimum motion cost
  int   max_pos       = (2*search_range+1)*(2*search_range+1);    // number of search positions
  int   blocksize_y   = params->blc_size[blocktype][1];            // vertical block size
  int   blocksize_x   = params->blc_size[blocktype][0];            // horizontal block size

  int   pred_x        = (pic_pix_x << 2) + pred_mv[0];       // predicted position x (in sub-pel units)
  int   pred_y        = (pic_pix_y << 2) + pred_mv[1];       // predicted position y (in sub-pel units)
  int   center_x      = pic_pix_x + mv[0];                        // center position x (in pel units)
  int   center_y      = pic_pix_y + mv[1];                        // center position y (in pel units)
  int   check_for_00  = (blocktype==1 && !params->rdopt && img->type!=B_SLICE && ref==0);
  int   dist_method = F_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 (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;
  }

  //===== set function for getting reference picture lines =====
  if ((center_x > search_range) && (center_x < img_width -1-search_range-blocksize_x) &&
    (center_y > search_range) && (center_y < img_height-1-search_range-blocksize_y)   )
  {
    ref_access_method = FAST_ACCESS;
  }
  else
  {
    ref_access_method = UMV_ACCESS;
  }

  //===== loop over all search positions =====
  for (pos=0; pos<max_pos; pos++)
  {
    //--- set candidate position (absolute position in pel units) ---
    cand_x = (center_x + spiral_search_x[pos])<<2;
    cand_y = (center_y + spiral_search_y[pos])<<2;

    //--- initialize motion cost (cost for motion vector) and check ---
    mcost = MV_COST_SMP (lambda_factor, cand_x, cand_y, pred_x, pred_y);
    if (check_for_00 && cand_x==pic_pix_x && cand_y==pic_pix_y)
    {
      mcost -= WEIGHTED_COST (lambda_factor, 16);
    }
    if (mcost >= min_mcost)   continue;

    //--- add residual cost to motion cost ---
    mcost += computeUniPred[dist_method](orig_pic, blocksize_y, blocksize_x,
      min_mcost - mcost, cand_x + IMG_PAD_SIZE_TIMES4, cand_y + IMG_PAD_SIZE_TIMES4);

    //--- check if motion cost is less than minimum cost ---
    if (mcost < min_mcost)
    {
      best_pos  = pos;
      min_mcost = mcost;
    }
  }


  //===== set best motion vector and return minimum motion cost =====
  if (best_pos)
  {
    mv[0] += spiral_search_x[best_pos];
    mv[1] += spiral_search_y[best_pos];
  }
  return min_mcost;
}

/*!
 ***********************************************************************
 * \brief
 *    Full pixel block motion search
 ***********************************************************************
 */
int                                                //  ==> minimum motion cost after search
FullPelBlockMotionBiPred (Macroblock *currMB,      // <--  current Macroblock
                          imgpel*   orig_pic,      // <--  original pixel values for the AxB block
                          short     ref,           // <--  reference frame (0... or -1 (backward))
                          int       list,          // <--  reference list
                          int       list_offset,   // <--  MBAFF list offset
                          char   ***refPic,        // <--  reference array
                          short ****tmp_mv,        // <--  mv array
                          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_mv1[2],   // <--  motion vector predictor from first list (x|y) in sub-pel units
                          short     pred_mv2[2],   // <--  motion vector predictor from second list (x|y) in sub-pel units
                          short     mv[2],         // <--> in: search center (x|y) / out: motion vector (x|y) - in pel units
                          short     static_mv[2],       // <--> in: search center (x|y) 
                          int       search_range,  // <--  1-d search range in pel units
                          int       min_mcost,     // <--  minimum motion cost (cost for center or huge value)
                          int       iteration_no,  // <--  bi pred iteration number
                          int       lambda_factor, // <--  lagrangian parameter for determining motion cost
                          int       apply_weights  // <--  perform weight based ME
                          ) 
{
  StorablePicture *ref_picture1 = listX[list       + list_offset][ref];
  StorablePicture *ref_picture2 = listX[(list ^ 1) + list_offset][0];
  short blocksize_y   = params->blc_size[blocktype][1];        // vertical block size
  short blocksize_x   = params->blc_size[blocktype][0];        // horizontal block size
  
  int   pos, mcost;

  int   best_pos      = 0;                                     // position with minimum motion cost
  int   max_pos       = (2*search_range+1)*(2*search_range+1); // number of search positions

  static MotionVector center1, center2, cand, pred1, pred2;
  pred1.mv_x   = (pic_pix_x << 2) + pred_mv1[0]; // predicted position x (in sub-pel units)
  pred1.mv_y   = (pic_pix_y << 2) + pred_mv1[1]; // predicted position y (in sub-pel units)
  pred2.mv_x   = (pic_pix_x << 2) + pred_mv2[0]; // predicted position x (in sub-pel units)
  pred2.mv_y   = (pic_pix_y << 2) + pred_mv2[1]; // predicted position y (in sub-pel units)
  center1.mv_x = pic_pix_x + mv[0];              // center position x (in pel units)
  center1.mv_y = pic_pix_y + mv[1];              // center position y (in pel units)
  center2.mv_x = pic_pix_x + static_mv[0];       // center position x of static mv (in pel units)
  center2.mv_y = pic_pix_y + static_mv[1];       // center position y of static mv (in pel units)

  ref_pic1_sub.luma = ref_picture1->p_curr_img_sub;
  ref_pic2_sub.luma = ref_picture2->p_curr_img_sub;

  img_width  = ref_picture1->size_x;
  img_height = ref_picture1->size_y;
  width_pad  = ref_picture1->size_x_pad;
  height_pad = ref_picture1->size_y_pad;

  if (apply_weights)
  {
    computeBiPred = computeBiPred2[F_PEL];
  }
  else
  {
    computeBiPred = computeBiPred1[F_PEL];
  }

  if ( ChromaMEEnable )
  {
    ref_pic1_sub.crcb[0] = ref_picture1->imgUV_sub[0];
    ref_pic1_sub.crcb[1] = ref_picture1->imgUV_sub[1];
    ref_pic2_sub.crcb[0] = ref_picture2->imgUV_sub[0];
    ref_pic2_sub.crcb[1] = ref_picture2->imgUV_sub[1];
    width_pad_cr  = ref_picture1->size_x_cr_pad;
    height_pad_cr = ref_picture1->size_y_cr_pad;
  }

  //===== set function for getting reference picture lines from reference 1 =====
  if ((center1.mv_x > search_range) && (center1.mv_x < img_width -1-search_range-blocksize_x) &&
    (center1.mv_y > search_range) && (center1.mv_y < img_height-1-search_range-blocksize_y)   )
  {
    bipred1_access_method = FAST_ACCESS;
  }
  else
  {
    bipred1_access_method = UMV_ACCESS;
  }

  //===== set function for getting reference picture lines from reference 2 =====
  if ((center2.mv_x > search_range) && (center2.mv_x < img_width -1-search_range-blocksize_x) &&
    (center2.mv_y > search_range) && (center2.mv_y < img_height-1-search_range-blocksize_y)   )
  {
    bipred2_access_method = FAST_ACCESS;
  }
  else
  {
    bipred2_access_method = UMV_ACCESS;
  }


  //===== loop over all search positions =====
  for (pos=0; pos<max_pos; pos++)
  {
    //--- set candidate position (absolute position in pel units) ---
    cand.mv_x = (center1.mv_x + spiral_search_x[pos])<<2;
    cand.mv_y = (center1.mv_y + spiral_search_y[pos])<<2;

    //--- initialize motion cost (cost for motion vector) and check ---
    mcost  = MV_COST_SMP (lambda_factor, cand.mv_x, cand.mv_y, pred1.mv_x, pred1.mv_y);
    mcost += MV_COST_SMP (lambda_factor, (center2.mv_x << 2), (center2.mv_y<<2), pred2.mv_x, pred2.mv_y);

    if (mcost >= min_mcost)   continue;

    //--- add residual cost to motion cost ---
    mcost += computeBiPred(orig_pic,
      blocksize_y, blocksize_x, min_mcost - mcost,
      cand.mv_x + IMG_PAD_SIZE_TIMES4, cand.mv_y + IMG_PAD_SIZE_TIMES4,
      (center2.mv_x << 2) + IMG_PAD_SIZE_TIMES4,
      (center2.mv_y << 2) + IMG_PAD_SIZE_TIMES4);

    //--- check if motion cost is less than minimum cost ---
    if (mcost < min_mcost)
    {
      best_pos  = pos;
      min_mcost = mcost;
    }
  }

  //===== set best motion vector and return minimum motion cost =====
  if (best_pos)
  {
    mv[0] += spiral_search_x[best_pos];
    mv[1] += spiral_search_y[best_pos];
  }
  return min_mcost;
}

/*!
 ***********************************************************************
 * \brief
 *    Sub pixel block motion search
 ***********************************************************************
 */
int                                               //  ==> minimum motion cost after search
SubPelBlockMotionSearch (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 in sub-pel units
                         short     mv[2],         // <--> in: search center / out: motion vector - 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,        // <--  lagrangian parameter for determining motion cost
                         int       apply_weights  // <--  use weight based ME
                         )
{
  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;
  int dist_method = H_PEL + 3 * apply_weights;
  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);
  int lambda_factor = lambda[H_PEL];

  ref_pic_sub.luma = ref_picture->p_curr_img_sub;
  width_pad  = ref_picture->size_x_pad;