erc_do_p.c

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#include "global.h"
#include "mbuffer.h"
#include "memalloc.h"
#include "erc_do.h"
#include "image.h"
#include "mc_prediction.h"
#include "macroblock.h"

extern int erc_mvperMB;
ImageParameters *erc_img;

// picture error concealment
// concealment_head points to first node in list, concealment_end points to
// last node in list. Initialize both to NULL, meaning no nodes in list yet
struct concealment_node *concealment_head = NULL;
struct concealment_node *concealment_end = NULL;

// static function declarations
static int concealByCopy(frame *recfr, int currMBNum, objectBuffer_t *object_list, int picSizeX);
static int concealByTrial(frame *recfr, imgpel *predMB,
                          int currMBNum, objectBuffer_t *object_list, int predBlocks[],
                          int picSizeX, int picSizeY, int *yCondition);
static int edgeDistortion (int predBlocks[], int currYBlockNum, imgpel *predMB,
                           imgpel *recY, int picSizeX, int regionSize);
static void copyBetweenFrames (frame *recfr, int currYBlockNum, int picSizeX, int regionSize);
static void buildPredRegionYUV(ImageParameters *img, int *mv, int x, int y, imgpel *predMB);

// picture error concealment
static void buildPredblockRegionYUV(ImageParameters *img, int *mv,
                                    int x, int y, imgpel *predMB, int list);
static void CopyImgData(imgpel **inputY, imgpel ***inputUV, imgpel **outputY, imgpel ***outputUV, 
                        int img_width, int img_height, int img_width_cr, int img_height_cr);

static void copyPredMB (int currYBlockNum, imgpel *predMB, frame *recfr,
                        int picSizeX, int regionSize);

static int uv_div[2][4] = {{0, 1, 1, 0}, {0, 1, 0, 0}}; //[x/y][yuv_format]

int ercConcealInterFrame(frame *recfr, objectBuffer_t *object_list,
                         int picSizeX, int picSizeY, ercVariables_t *errorVar, int chroma_format_idc )
{
  int lastColumn = 0, lastRow = 0, predBlocks[8];
  int lastCorruptedRow = -1, firstCorruptedRow = -1, currRow = 0,
    row, column, columnInd, areaHeight = 0, i = 0;
  imgpel *predMB;

  /* if concealment is on */
  if ( errorVar && errorVar->concealment )
  {
    /* if there are segments to be concealed */
    if ( errorVar->nOfCorruptedSegments )
    {
      if (chroma_format_idc != YUV400)
        predMB = (imgpel *) malloc ( (256 + (img->mb_cr_size_x*img->mb_cr_size_y)*2) * sizeof (imgpel));
      else
        predMB = (imgpel *) malloc(256 * sizeof (imgpel));

      if ( predMB == NULL ) no_mem_exit("ercConcealInterFrame: predMB");

      lastRow = (int) (picSizeY>>4);
      lastColumn = (int) (picSizeX>>4);

      for ( columnInd = 0; columnInd < lastColumn; columnInd ++)
      {

        column = ((columnInd%2) ? (lastColumn - columnInd/2 -1) : (columnInd/2));

        for ( row = 0; row < lastRow; row++)
        {

          if ( errorVar->yCondition[MBxy2YBlock(column, row, 0, picSizeX)] <= ERC_BLOCK_CORRUPTED )
          {                           // ERC_BLOCK_CORRUPTED (1) or ERC_BLOCK_EMPTY (0)
            firstCorruptedRow = row;
            /* find the last row which has corrupted blocks (in same continuous area) */
            for ( lastCorruptedRow = row+1; lastCorruptedRow < lastRow; lastCorruptedRow++)
            {
              /* check blocks in the current column */
              if (errorVar->yCondition[MBxy2YBlock(column, lastCorruptedRow, 0, picSizeX)] > ERC_BLOCK_CORRUPTED)
              {
                /* current one is already OK, so the last was the previous one */
                lastCorruptedRow --;
                break;
              }
            }
            if ( lastCorruptedRow >= lastRow )
            {
              /* correct only from above */
              lastCorruptedRow = lastRow-1;
              for ( currRow = firstCorruptedRow; currRow < lastRow; currRow++ )
              {

                ercCollect8PredBlocks (predBlocks, (currRow<<1), (column<<1),
                  errorVar->yCondition, (lastRow<<1), (lastColumn<<1), 2, 0);

                if(erc_mvperMB >= MVPERMB_THR)
                  concealByTrial(recfr, predMB,
                    currRow*lastColumn+column, object_list, predBlocks,
                    picSizeX, picSizeY,
                    errorVar->yCondition);
                else
                  concealByCopy(recfr, currRow*lastColumn+column,
                    object_list, picSizeX);

                ercMarkCurrMBConcealed (currRow*lastColumn+column, -1, picSizeX, errorVar);
              }
              row = lastRow;
            }
            else if ( firstCorruptedRow == 0 )
            {
              /* correct only from below */
              for ( currRow = lastCorruptedRow; currRow >= 0; currRow-- )
              {

                ercCollect8PredBlocks (predBlocks, (currRow<<1), (column<<1),
                  errorVar->yCondition, (lastRow<<1), (lastColumn<<1), 2, 0);

                if(erc_mvperMB >= MVPERMB_THR)
                  concealByTrial(recfr, predMB,
                    currRow*lastColumn+column, object_list, predBlocks,
                    picSizeX, picSizeY,
                    errorVar->yCondition);
                else
                  concealByCopy(recfr, currRow*lastColumn+column,
                    object_list, picSizeX);

                ercMarkCurrMBConcealed (currRow*lastColumn+column, -1, picSizeX, errorVar);
              }

              row = lastCorruptedRow+1;
            }
            else
            {
              /* correct bi-directionally */

              row = lastCorruptedRow+1;

              areaHeight = lastCorruptedRow-firstCorruptedRow+1;

              /*
              *  Conceal the corrupted area switching between the up and the bottom rows
              */
              for ( i = 0; i < areaHeight; i++)
              {
                if ( i % 2 )
                {
                  currRow = lastCorruptedRow;
                  lastCorruptedRow --;
                }
                else
                {
                  currRow = firstCorruptedRow;
                  firstCorruptedRow ++;
                }

                ercCollect8PredBlocks (predBlocks, (currRow<<1), (column<<1),
                  errorVar->yCondition, (lastRow<<1), (lastColumn<<1), 2, 0);

                if(erc_mvperMB >= MVPERMB_THR)
                  concealByTrial(recfr, predMB,
                    currRow*lastColumn+column, object_list, predBlocks,
                    picSizeX, picSizeY,
                    errorVar->yCondition);
                else
                  concealByCopy(recfr, currRow*lastColumn+column,
                    object_list, picSizeX);

                ercMarkCurrMBConcealed (currRow*lastColumn+column, -1, picSizeX, errorVar);

              }
            }
            lastCorruptedRow = -1;
            firstCorruptedRow = -1;
          }
        }
      }

      free(predMB);
    }
    return 1;
  }
  else
    return 0;
}

static int concealByCopy(frame *recfr, int currMBNum,
                         objectBuffer_t *object_list, int picSizeX)
{
  objectBuffer_t *currRegion;

  currRegion = object_list+(currMBNum<<2);
  currRegion->regionMode = REGMODE_INTER_COPY;

  currRegion->xMin = (xPosMB(currMBNum,picSizeX)<<4);
  currRegion->yMin = (yPosMB(currMBNum,picSizeX)<<4);

  copyBetweenFrames (recfr, MBNum2YBlock(currMBNum,0,picSizeX), picSizeX, 16);

  return 0;
}

static void copyBetweenFrames (frame *recfr, int currYBlockNum, int picSizeX, int regionSize)
{
  int j, k, location, xmin, ymin;
  StorablePicture* refPic = listX[0][0];

  /* set the position of the region to be copied */
  xmin = (xPosYBlock(currYBlockNum,picSizeX)<<3);
  ymin = (yPosYBlock(currYBlockNum,picSizeX)<<3);

  for (j = ymin; j < ymin + regionSize; j++)
    for (k = xmin; k < xmin + regionSize; k++)
    {
      location = j * picSizeX + k;
//th      recfr->yptr[location] = dec_picture->imgY[j][k];
      recfr->yptr[location] = refPic->imgY[j][k];
    }

    for (j = ymin >> uv_div[1][dec_picture->chroma_format_idc]; j < (ymin + regionSize) >> uv_div[1][dec_picture->chroma_format_idc]; j++)
      for (k = xmin >> uv_div[0][dec_picture->chroma_format_idc]; k < (xmin + regionSize) >> uv_div[0][dec_picture->chroma_format_idc]; k++)
      {
//        location = j * picSizeX / 2 + k;
        location = ((j * picSizeX) >> uv_div[0][dec_picture->chroma_format_idc]) + k;

//th        recfr->uptr[location] = dec_picture->imgUV[0][j][k];
//th        recfr->vptr[location] = dec_picture->imgUV[1][j][k];
        recfr->uptr[location] = refPic->imgUV[0][j][k];
        recfr->vptr[location] = refPic->imgUV[1][j][k];
      }
}

static int concealByTrial(frame *recfr, imgpel *predMB,
                          int currMBNum, objectBuffer_t *object_list, int predBlocks[],
                          int picSizeX, int picSizeY, int *yCondition)
{
  int predMBNum = 0, numMBPerLine,
      compSplit1 = 0, compSplit2 = 0, compLeft = 1, comp = 0, compPred, order = 1,
      fInterNeighborExists, numIntraNeighbours,
      fZeroMotionChecked, predSplitted = 0,
      threshold = ERC_BLOCK_OK,
      minDist, currDist, i, k, bestDir;
  int regionSize;
  objectBuffer_t *currRegion;
  int mvBest[3] , mvPred[3], *mvptr;

  numMBPerLine = (int) (picSizeX>>4);

  img->current_mb_nr = currMBNum;

  comp = 0;
  regionSize = 16;

  do
  { /* 4 blocks loop */

    currRegion = object_list+(currMBNum<<2)+comp;

    /* set the position of the region to be concealed */

    currRegion->xMin = (xPosYBlock(MBNum2YBlock(currMBNum,comp,picSizeX),picSizeX)<<3);
    currRegion->yMin = (yPosYBlock(MBNum2YBlock(currMBNum,comp,picSizeX),picSizeX)<<3);

    do
    { /* reliability loop */

      minDist = 0;
      fInterNeighborExists = 0;
      numIntraNeighbours = 0;
      fZeroMotionChecked = 0;

      /* loop the 4 neighbours */
      for (i = 4; i < 8; i++)
      {

        /* if reliable, try it */
        if (predBlocks[i] >= threshold)
        {
          switch (i)
          {
          case 4:
            predMBNum = currMBNum-numMBPerLine;
            compSplit1 = 2;
            compSplit2 = 3;
            break;

          case 5:
            predMBNum = currMBNum-1;
            compSplit1 = 1;
            compSplit2 = 3;
            break;

          case 6:
            predMBNum = currMBNum+numMBPerLine;
            compSplit1 = 0;
            compSplit2 = 1;
            break;

          case 7:
            predMBNum = currMBNum+1;
            compSplit1 = 0;
            compSplit2 = 2;
            break;
          }

          /* try the concealment with the Motion Info of the current neighbour
          only try if the neighbour is not Intra */
          if (isBlock(object_list,predMBNum,compSplit1,INTRA) ||
            isBlock(object_list,predMBNum,compSplit2,INTRA))
          {
            numIntraNeighbours++;
          }
          else
          {
            /* if neighbour MB is splitted, try both neighbour blocks */
            for (predSplitted = isSplitted(object_list, predMBNum),
              compPred = compSplit1;
              predSplitted >= 0;
              compPred = compSplit2,
              predSplitted -= ((compSplit1 == compSplit2) ? 2 : 1))
            {

              /* if Zero Motion Block, do the copying. This option is tried only once */
              if (isBlock(object_list, predMBNum, compPred, INTER_COPY))
              {

                if (fZeroMotionChecked)
                {
                  continue;
                }
                else
                {
                  fZeroMotionChecked = 1;

                  mvPred[0] = mvPred[1] = 0;
                  mvPred[2] = 0;

                  buildPredRegionYUV(erc_img, mvPred, currRegion->xMin, currRegion->yMin, predMB);
                }
              }
              /* build motion using the neighbour's Motion Parameters */
              else if (isBlock(object_list,predMBNum,compPred,INTRA))
              {
                continue;
              }
              else
              {
                mvptr = getParam(object_list, predMBNum, compPred, mv);

                mvPred[0] = mvptr[0];
                mvPred[1] = mvptr[1];
                mvPred[2] = mvptr[2];

                buildPredRegionYUV(erc_img, mvPred, currRegion->xMin, currRegion->yMin, predMB);
              }

              /* measure absolute boundary pixel difference */
              currDist = edgeDistortion(predBlocks,
                MBNum2YBlock(currMBNum,comp,picSizeX),
                predMB, recfr->yptr, picSizeX, regionSize);

              /* if so far best -> store the pixels as the best concealment */
              if (currDist < minDist || !fInterNeighborExists)
              {

                minDist = currDist;
                bestDir = i;

                for (k=0;k<3;k++)
                  mvBest[k] = mvPred[k];

                currRegion->regionMode =
                  (isBlock(object_list, predMBNum, compPred, INTER_COPY)) ?
                  ((regionSize == 16) ? REGMODE_INTER_COPY : REGMODE_INTER_COPY_8x8) :
                  ((regionSize == 16) ? REGMODE_INTER_PRED : REGMODE_INTER_PRED_8x8);

                copyPredMB(MBNum2YBlock(currMBNum,comp,picSizeX), predMB, recfr,
                  picSizeX, regionSize);
              }

              fInterNeighborExists = 1;
            }
          }
        }
    }

    threshold--;

    } while ((threshold >= ERC_BLOCK_CONCEALED) && (fInterNeighborExists == 0));

    /* always try zero motion */
    if (!fZeroMotionChecked)
    {
      mvPred[0] = mvPred[1] = 0;
      mvPred[2] = 0;

      buildPredRegionYUV(erc_img, mvPred, currRegion->xMin, currRegion->yMin, predMB);

      currDist = edgeDistortion(predBlocks,
        MBNum2YBlock(currMBNum,comp,picSizeX),
        predMB, recfr->yptr, picSizeX, regionSize);

      if (currDist < minDist || !fInterNeighborExists)
      {

        minDist = currDist;
        for (k=0;k<3;k++)
          mvBest[k] = mvPred[k];

        currRegion->regionMode =
          ((regionSize == 16) ? REGMODE_INTER_COPY : REGMODE_INTER_COPY_8x8);

        copyPredMB(MBNum2YBlock(currMBNum,comp,picSizeX), predMB, recfr,
          picSizeX, regionSize);
      }
    }

    for (i=0; i<3; i++)
      currRegion->mv[i] = mvBest[i];

    yCondition[MBNum2YBlock(currMBNum,comp,picSizeX)] = ERC_BLOCK_CONCEALED;
    comp = (comp+order+4)%4;
    compLeft--;

    } while (compLeft);

    return 0;
}

static void buildPredRegionYUV(ImageParameters *img, int *mv, int x, int y, imgpel *predMB)
{
  static imgpel **tmp_block;
  int i=0, j=0, ii=0, jj=0,i1=0,j1=0,j4=0,i4=0;
  int jf=0;
  int uv;
  int vec1_x=0,vec1_y=0;
  int ioff,joff;
  imgpel *pMB = predMB;

  int ii0,jj0,ii1,jj1,if1,jf1,if0,jf0;
  int mv_mul;

  //FRExt
  int f1_x, f1_y, f2_x, f2_y, f3, f4, ifx;
  int b8, b4;
  int yuv = dec_picture->chroma_format_idc - 1;

  int ref_frame = imax (mv[2], 0); // !!KS: quick fix, we sometimes seem to get negative ref_pic here, so restrict to zero and above

  // This should be allocated only once. 
  get_mem2Dpel(&tmp_block, MB_BLOCK_SIZE, MB_BLOCK_SIZE);

  /* Update coordinates of the current concealed macroblock */
  img->mb_x = x/MB_BLOCK_SIZE;
  img->mb_y = y/MB_BLOCK_SIZE;
  img->block_y = img->mb_y * BLOCK_SIZE;
  img->pix_c_y = img->mb_y * img->mb_cr_size_y;
  img->block_x = img->mb_x * BLOCK_SIZE;
  img->pix_c_x = img->mb_x * img->mb_cr_size_x;

  mv_mul=4;

  // luma *******************************************************

  for(j=0;j<MB_BLOCK_SIZE/BLOCK_SIZE;j++)
  {
    joff=j*4;
    j4=img->block_y+j;
    for(i=0;i<MB_BLOCK_SIZE/BLOCK_SIZE;i++)
    {
      ioff=i*4;
      i4=img->block_x+i;

      vec1_x = i4*4*mv_mul + mv[0];
      vec1_y = j4*4*mv_mul + mv[1];

      get_block_luma(PLANE_Y, listX[0][ref_frame], vec1_x, vec1_y, BLOCK_SIZE, BLOCK_SIZE, img, tmp_block);  

      for(ii=0;ii<BLOCK_SIZE;ii++)
        for(jj=0;jj<MB_BLOCK_SIZE/BLOCK_SIZE;jj++)
          img->mb_pred[LumaComp][jj+joff][ii+ioff]=tmp_block[jj][ii];
    }
  }


  for (j = 0; j < 16; j++)
  {
    for (i = 0; i < 16; i++)
    {
      pMB[j*16+i] = img->mb_pred[LumaComp][j][i];
    }
  }
  pMB += 256;

  if (dec_picture->chroma_format_idc != YUV400)
  {
    // chroma *******************************************************
    f1_x = 64/img->mb_cr_size_x;
    f2_x=f1_x-1;

    f1_y = 64/img->mb_cr_size_y;
    f2_y=f1_y-1;

    f3=f1_x*f1_y;
    f4=f3>>1;

    for(uv=0;uv<2;uv++)
    {
      for (b8=0;b8<(img->num_uv_blocks);b8++)
      {
        for(b4=0;b4<4;b4++)
        {
          joff = subblk_offset_y[yuv][b8][b4];
          j4=img->pix_c_y+joff;
          ioff = subblk_offset_x[yuv][b8][b4];
          i4=img->pix_c_x+ioff;

          for(jj=0;jj<4;jj++)
          {
            jf=(j4+jj)/(img->mb_cr_size_y/4);     // jf  = Subblock_y-coordinate
            for(ii=0;ii<4;ii++)
            {
              ifx=(i4+ii)/(img->mb_cr_size_x/4);  // ifx = Subblock_x-coordinate

              i1=(i4+ii)*f1_x + mv[0];
              j1=(j4+jj)*f1_y + mv[1];

              ii0=iClip3 (0, dec_picture->size_x_cr-1, i1/f1_x);
              jj0=iClip3 (0, dec_picture->size_y_cr-1, j1/f1_y);
              ii1=iClip3 (0, dec_picture->size_x_cr-1, ((i1+f2_x)/f1_x));
              jj1=iClip3 (0, dec_picture->size_y_cr-1, ((j1+f2_y)/f1_y));

              if1=(i1 & f2_x);
              jf1=(j1 & f2_y);
              if0=f1_x-if1;
              jf0=f1_y-jf1;

              img->mb_pred[uv + 1][jj+joff][ii+ioff]=(if0*jf0*listX[0][ref_frame]->imgUV[uv][jj0][ii0]+
                if1*jf0*listX[0][ref_frame]->imgUV[uv][jj0][ii1]+
                if0*jf1*listX[0][ref_frame]->imgUV[uv][jj1][ii0]+
                if1*jf1*listX[0][ref_frame]->imgUV[uv][jj1][ii1]+f4)/f3;
            }
          }
        }
      }

      for (j = 0; j < 8; j++)
      {
        for (i = 0; i < 8; i++)
        {
          pMB[j*8+i] = img->mb_pred[uv + 1][j][i];
        }
      }
      pMB += 64;

    }
  }
  // We should allocate this memory only once.
  free_mem2Dpel(tmp_block); 
}
static void copyPredMB (int currYBlockNum, imgpel *predMB, frame *recfr,
                        int picSizeX, int regionSize)
{

  int j, k, xmin, ymin, xmax, ymax;
  int locationTmp, locationPred;
  int uv_x = uv_div[0][dec_picture->chroma_format_idc];
  int uv_y = uv_div[1][dec_picture->chroma_format_idc];

  xmin = (xPosYBlock(currYBlockNum,picSizeX)<<3);
  ymin = (yPosYBlock(currYBlockNum,picSizeX)<<3);
  xmax = xmin + regionSize -1;
  ymax = ymin + regionSize -1;

  for (j = ymin; j <= ymax; j++)
  {
    for (k = xmin; k <= xmax; k++)
    {
      locationPred = j * picSizeX + k;
      locationTmp = (j-ymin) * 16 + (k-xmin);
      dec_picture->imgY[j][k] = predMB[locationTmp];
    }
  }

  if (dec_picture->chroma_format_idc != YUV400)
  {
    for (j = (ymin>>uv_y); j <= (ymax>>uv_y); j++)
    {
      for (k = (xmin>>uv_x); k <= (xmax>>uv_x); k++)
      {
        locationPred = ((j * picSizeX) >> uv_x) + k;
        locationTmp = (j-(ymin>>uv_y)) * img->mb_cr_size_x + (k-(xmin>>1)) + 256;
        dec_picture->imgUV[0][j][k] = predMB[locationTmp];

        locationTmp += 64;

        dec_picture->imgUV[1][j][k] = predMB[locationTmp];
      }
    }
  }
}

static int edgeDistortion (int predBlocks[], int currYBlockNum, imgpel *predMB,
                           imgpel *recY, int picSizeX, int regionSize)
{
  int i, j, distortion, numOfPredBlocks, threshold = ERC_BLOCK_OK;
  imgpel *currBlock = NULL, *neighbor = NULL;
  int currBlockOffset = 0;

  currBlock = recY + (yPosYBlock(currYBlockNum,picSizeX)<<3)*picSizeX + (xPosYBlock(currYBlockNum,picSizeX)<<3);

  do
  {

    distortion = 0; numOfPredBlocks = 0;

    // loop the 4 neighbors
    for (j = 4; j < 8; j++)
    {
      /* if reliable, count boundary pixel difference */
      if (predBlocks[j] >= threshold)
      {

        switch (j)
        {
        case 4:
          neighbor = currBlock - picSizeX;
          for ( i = 0; i < regionSize; i++ )
          {
            distortion += iabs((int)(predMB[i] - neighbor[i]));
          }
          break;
        case 5:
          neighbor = currBlock - 1;
          for ( i = 0; i < regionSize; i++ )
          {
            distortion += iabs((int)(predMB[i*16] - neighbor[i*picSizeX]));
          }
          break;
        case 6:
          neighbor = currBlock + regionSize*picSizeX;
          currBlockOffset = (regionSize-1)*16;
          for ( i = 0; i < regionSize; i++ )
          {
            distortion += iabs((int)(predMB[i+currBlockOffset] - neighbor[i]));
          }
          break;
        case 7:
          neighbor = currBlock + regionSize;
          currBlockOffset = regionSize-1;
          for ( i = 0; i < regionSize; i++ )
          {
            distortion += iabs((int)(predMB[i*16+currBlockOffset] - neighbor[i*picSizeX]));
          }
          break;
        }

        numOfPredBlocks++;
      }
    }

    threshold--;
    if (threshold < ERC_BLOCK_CONCEALED)
      break;
  } while (numOfPredBlocks == 0);

  if(numOfPredBlocks == 0)
  {
    return 0;
    // assert (numOfPredBlocks != 0); !!!KS hmm, trying to continue...
  }
  return (distortion/numOfPredBlocks);
}

// picture error concealment below

static void buildPredblockRegionYUV(ImageParameters *img, int *mv,
                                    int x, int y, imgpel *predMB, int list)
{
  static imgpel **tmp_block;
  int i=0,j=0,ii=0,jj=0,i1=0,j1=0,j4=0,i4=0;
  int jf=0;
  int uv;
  int vec1_x=0,vec1_y=0;
  int ioff,joff;
  imgpel *pMB = predMB;

  int ii0,jj0,ii1,jj1,if1,jf1,if0,jf0;
  int mv_mul;

  //FRExt
  int f1_x, f1_y, f2_x, f2_y, f3, f4, ifx;
  int yuv = dec_picture->chroma_format_idc - 1;

  int ref_frame = mv[2];

  get_mem2Dpel(&tmp_block, MB_BLOCK_SIZE, MB_BLOCK_SIZE);

  /* Update coordinates of the current concealed macroblock */

  img->mb_x = x/BLOCK_SIZE;
  img->mb_y = y/BLOCK_SIZE;
  img->block_y = img->mb_y * BLOCK_SIZE;
  img->pix_c_y = img->mb_y * img->mb_cr_size_y/4;
  img->block_x = img->mb_x * BLOCK_SIZE;
  img->pix_c_x = img->mb_x * img->mb_cr_size_x/4;

  mv_mul=4;

  // luma *******************************************************

  vec1_x = x*mv_mul + mv[0];
  vec1_y = y*mv_mul + mv[1];
  get_block_luma(PLANE_Y, listX[list][ref_frame], vec1_x,vec1_y, BLOCK_SIZE, BLOCK_SIZE, img, tmp_block);  

  for(jj=0;jj<MB_BLOCK_SIZE/BLOCK_SIZE;jj++)
    for(ii=0;ii<BLOCK_SIZE;ii++)
      img->mb_pred[LumaComp][jj][ii]=tmp_block[jj][ii];


  for (j = 0; j < 4; j++)
  {
    for (i = 0; i < 4; i++)
    {
      pMB[j*4+i] = img->mb_pred[LumaComp][j][i];
    }
  }
  pMB += 16;

  if (dec_picture->chroma_format_idc != YUV400)
  {
    // chroma *******************************************************
    f1_x = 64/(img->mb_cr_size_x);
    f2_x=f1_x-1;

    f1_y = 64/(img->mb_cr_size_y);
    f2_y=f1_y-1;

    f3=f1_x*f1_y;
    f4=f3>>1;

    for(uv=0;uv<2;uv++)
    {
      joff = subblk_offset_y[yuv][0][0];
      j4=img->pix_c_y+joff;
      ioff = subblk_offset_x[yuv][0][0];
      i4=img->pix_c_x+ioff;

      for(jj=0;jj<2;jj++)
      {
        jf=(j4+jj)/(img->mb_cr_size_y/4);     // jf  = Subblock_y-coordinate
        for(ii=0;ii<2;ii++)
        {
          ifx=(i4+ii)/(img->mb_cr_size_x/4);  // ifx = Subblock_x-coordinate

          i1=(i4+ii)*f1_x + mv[0];
          j1=(j4+jj)*f1_y + mv[1];

          ii0=iClip3 (0, dec_picture->size_x_cr-1, i1/f1_x);
          jj0=iClip3 (0, dec_picture->size_y_cr-1, j1/f1_y);
          ii1=iClip3 (0, dec_picture->size_x_cr-1, ((i1+f2_x)/f1_x));
          jj1=iClip3 (0, dec_picture->size_y_cr-1, ((j1+f2_y)/f1_y));

          if1=(i1 & f2_x);
          jf1=(j1 & f2_y);
          if0=f1_x-if1;
          jf0=f1_y-jf1;

          img->mb_pred[uv + 1][jj][ii]=(if0*jf0*listX[list][ref_frame]->imgUV[uv][jj0][ii0]+
            if1*jf0*listX[list][ref_frame]->imgUV[uv][jj0][ii1]+
            if0*jf1*listX[list][ref_frame]->imgUV[uv][jj1][ii0]+
            if1*jf1*listX[list][ref_frame]->imgUV[uv][jj1][ii1]+f4)/f3;
        }
      }

      for (j = 0; j < 2; j++)
      {
        for (i = 0; i < 2; i++)
        {
          pMB[j*2+i] = img->mb_pred[uv + 1][j][i];
        }
      }
      pMB += 4;

    }
  }
  free_mem2Dpel(tmp_block);
}

static int compare_pic_by_pic_num_desc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->pic_num < (*(StorablePicture**)arg2)->pic_num)
    return 1;
  if ( (*(StorablePicture**)arg1)->pic_num > (*(StorablePicture**)arg2)->pic_num)
    return -1;
  else
    return 0;
}

static int compare_pic_by_lt_pic_num_asc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->long_term_pic_num < (*(StorablePicture**)arg2)->long_term_pic_num)
    return -1;
  if ( (*(StorablePicture**)arg1)->long_term_pic_num > (*(StorablePicture**)arg2)->long_term_pic_num)
    return 1;
  else
    return 0;
}

static int compare_pic_by_poc_asc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->poc < (*(StorablePicture**)arg2)->poc)
    return -1;
  if ( (*(StorablePicture**)arg1)->poc > (*(StorablePicture**)arg2)->poc)
    return 1;
  else
    return 0;
}


static int compare_pic_by_poc_desc( const void *arg1, const void *arg2 )
{
  if ( (*(StorablePicture**)arg1)->poc < (*(StorablePicture**)arg2)->poc)
    return 1;
  if ( (*(StorablePicture**)arg1)->poc > (*(StorablePicture**)arg2)->poc)
    return -1;
  else
    return 0;
}

static void CopyImgData(imgpel **inputY, imgpel ***inputUV, imgpel **outputY, imgpel ***outputUV, 
                        int img_width, int img_height, int img_width_cr, int img_height_cr)
{
  int x, y;

  for (y=0; y<img_height; y++)
    for (x=0; x<img_width; x++)
      outputY[y][x] = inputY[y][x];

  for (y=0; y<img_height_cr; y++)
    for (x=0; x<img_width_cr; x++)
    {
      outputUV[0][y][x] = inputUV[0][y][x];
      outputUV[1][y][x] = inputUV[1][y][x];
    }
}

static StorablePicture* get_last_ref_pic_from_dpb()
{
  int used_size = dpb.used_size - 1;
  int i;

  for(i = used_size; i >= 0; i--)
  {
    if (dpb.fs[i]->is_used==3)
    {
      if (((dpb.fs[i]->frame->used_for_reference) &&
        (!dpb.fs[i]->frame->is_long_term)) /*||  ((dpb.fs[i]->frame->used_for_reference==0)
                                           && (dpb.fs[i]->frame->slice_type == P_SLICE))*/ )
      {
        return dpb.fs[i]->frame;
      }
    }
  }

  return NULL;
}

static void copy_to_conceal(StorablePicture *src, StorablePicture *dst, ImageParameters *img)
{
  int i=0;
  int mv[3];
  int multiplier;
  imgpel *predMB, *storeYUV;
  int j, y, x, mb_height, mb_width, ii=0, jj=0;
  int uv;
  int mm, nn;
  int scale = 1;
  // struct inp_par *test;

  img->current_mb_nr = 0;

  dst->PicSizeInMbs  = src->PicSizeInMbs;

  dst->slice_type = src->slice_type = img->conceal_slice_type;

  dst->idr_flag = FALSE; //since we do not want to clears the ref list

  dst->no_output_of_prior_pics_flag = src->no_output_of_prior_pics_flag;
  dst->long_term_reference_flag = src->long_term_reference_flag;
  dst->adaptive_ref_pic_buffering_flag = src->adaptive_ref_pic_buffering_flag = 0;
  dst->chroma_format_idc = src->chroma_format_idc;
  dst->frame_mbs_only_flag = src->frame_mbs_only_flag;
  dst->frame_cropping_flag = src->frame_cropping_flag;
  dst->frame_cropping_rect_left_offset = src->frame_cropping_rect_left_offset;
  dst->frame_cropping_rect_right_offset = src->frame_cropping_rect_right_offset;
  dst->frame_cropping_rect_bottom_offset = src->frame_cropping_rect_bottom_offset;
  dst->frame_cropping_rect_top_offset = src->frame_cropping_rect_top_offset;
  dst->qp = src->qp;
  dst->slice_qp_delta = src->slice_qp_delta;

  dec_picture = src;

  // Conceals the missing frame by frame copy concealment
  if (img->conceal_mode==1)
  {
    // We need these initializations for using deblocking filter for frame copy
    // concealment as well.
    dst->PicWidthInMbs = src->PicWidthInMbs;
    dst->PicSizeInMbs = src->PicSizeInMbs;

    CopyImgData( src->imgY, src->imgUV, dst->imgY, dst->imgUV, img->width, img->height, img->width_cr, img->height_cr);
  }

  // Conceals the missing frame by motion vector copy concealment
  if (img->conceal_mode==2)
  {
    if (dec_picture->chroma_format_idc != YUV400)
    {
      storeYUV = (imgpel *) malloc ( (16 + (img->mb_cr_size_x*img->mb_cr_size_y)*2/16) * sizeof (imgpel));
    }
    else
    {
      storeYUV = (imgpel *) malloc (16  * sizeof (imgpel));
    }

    erc_img = img;

    dst->PicWidthInMbs = src->PicWidthInMbs;
    dst->PicSizeInMbs = src->PicSizeInMbs;
    mb_width = dst->PicWidthInMbs;
    mb_height = (dst->PicSizeInMbs)/(dst->PicWidthInMbs);
    scale = (img->conceal_slice_type == B_SLICE) ? 2 : 1;

    if(img->conceal_slice_type == B_SLICE)
      init_lists_for_non_reference_loss(dst->slice_type, img->currentSlice->structure);
    else
      init_lists(dst->slice_type, img->currentSlice->structure);

    multiplier = BLOCK_SIZE;

    for(i=0;i<mb_height*4;i++)
    {
      mm = i * BLOCK_SIZE;
      for(j=0;j<mb_width*4;j++)
      {
        nn = j * BLOCK_SIZE;

        mv[0] = src->motion.mv[LIST_0][i][j][0] / scale;
        mv[1] = src->motion.mv[LIST_0][i][j][1] / scale;
        mv[2] = src->motion.ref_idx[LIST_0][i][j];

        if(mv[2]<0)
          mv[2]=0;

        dst->motion.mv[LIST_0][i][j][0] = mv[0];
        dst->motion.mv[LIST_0][i][j][1] = mv[1];
        dst->motion.ref_idx[LIST_0][i][j] = mv[2];

        x = (j) * multiplier;
        y = (i) * multiplier;

        if ((mm%16==0) && (nn%16==0))
          img->current_mb_nr++;

        buildPredblockRegionYUV(erc_img, mv, x, y, storeYUV, LIST_0);

        predMB = storeYUV;

        for(ii=0;ii<multiplier;ii++)
        {
          for(jj=0;jj<multiplier;jj++)
          {
            dst->imgY[i*multiplier+ii][j*multiplier+jj] = predMB[ii*(multiplier)+jj];
          }
        }

        predMB = predMB + (multiplier*multiplier);

        if (dec_picture->chroma_format_idc != YUV400)
        {

          for(uv=0;uv<2;uv++)
          {
            for(ii=0;ii< (multiplier/2);ii++)
            {
              for(jj=0;jj< (multiplier/2);jj++)
              {
                dst->imgUV[uv][i*multiplier/2 +ii][j*multiplier/2 +jj] = predMB[ii*(multiplier/2)+jj];
              }
            }
            predMB = predMB + (multiplier*multiplier/4);
          }
        }
      }
    }
    free(storeYUV);
  }
}

static void
copy_prev_pic_to_concealed_pic(StorablePicture *picture, ImageParameters *img)
{

  StorablePicture *ref_pic;
  /* get the last ref pic in dpb */
  ref_pic = get_last_ref_pic_from_dpb();

  assert(ref_pic != NULL);

  /* copy all the struc from this to current concealment pic */
  img->conceal_slice_type = P_SLICE;
  copy_to_conceal(ref_pic, picture, img);
}


void conceal_lost_frames(ImageParameters *img)
{
  int CurrFrameNum;
  int UnusedShortTermFrameNum;
  StorablePicture *picture = NULL;
  int tmp1 = img->delta_pic_order_cnt[0];
  int tmp2 = img->delta_pic_order_cnt[1];
  int i;

  img->delta_pic_order_cnt[0] = img->delta_pic_order_cnt[1] = 0;

  // printf("A gap in frame number is found, try to fill it.\n");

  if(img->IDR_concealment_flag == 1)
  {
    // Conceals an IDR frame loss. Uses the reference frame in the previous
    // GOP for concealment.
    UnusedShortTermFrameNum = 0;
    img->last_ref_pic_poc = -img->poc_gap;
    img->earlier_missing_poc = 0;
  }
  else
    UnusedShortTermFrameNum = (img->pre_frame_num + 1) % img->MaxFrameNum;

  CurrFrameNum = img->frame_num;

  while (CurrFrameNum != UnusedShortTermFrameNum)
  {
    picture = alloc_storable_picture (FRAME, img->width, img->height, img->width_cr, img->height_cr);

    picture->coded_frame = 1;
    picture->pic_num = UnusedShortTermFrameNum;
    picture->frame_num = UnusedShortTermFrameNum;
    picture->non_existing = 0;
    picture->is_output = 0;
    picture->used_for_reference = 1;
    picture->concealed_pic = 1;

    picture->adaptive_ref_pic_buffering_flag = 0;

    img->frame_num = UnusedShortTermFrameNum;

    picture->top_poc=img->last_ref_pic_poc + img->ref_poc_gap;
    picture->bottom_poc=picture->top_poc;
    picture->frame_poc=picture->top_poc;
    picture->poc=picture->top_poc;
    img->last_ref_pic_poc = picture->poc;

    copy_prev_pic_to_concealed_pic(picture, img);

    //if (UnusedShortTermFrameNum == 0)
    if(img->IDR_concealment_flag == 1)
    {
      picture->slice_type = I_SLICE;
      picture->idr_flag = TRUE;
      flush_dpb();
      picture->top_poc= 0;
      picture->bottom_poc=picture->top_poc;
      picture->frame_poc=picture->top_poc;
      picture->poc=picture->top_poc;
      img->last_ref_pic_poc = picture->poc;
    }

    store_picture_in_dpb(picture);

    picture=NULL;

    img->pre_frame_num = UnusedShortTermFrameNum;
    UnusedShortTermFrameNum = (UnusedShortTermFrameNum + 1) % img->MaxFrameNum;

    // update reference flags and set current flag.
    for(i=16;i>0;i--)
    {
      ref_flag[i] = ref_flag[i-1];
    }
    ref_flag[0] = 0;
  }
  img->delta_pic_order_cnt[0] = tmp1;
  img->delta_pic_order_cnt[1] = tmp2;
  img->frame_num = CurrFrameNum;
}

void update_ref_list_for_concealment()
{
  unsigned i, j;
  for (i=0, j=0; i<dpb.used_size; i++)
  {
    if (dpb.fs[i]->concealment_reference)
    {
      dpb.fs_ref[j++]=dpb.fs[i];
    }
  }

  dpb.ref_frames_in_buffer = active_pps->num_ref_idx_l0_active_minus1;
}

void init_lists_for_non_reference_loss(int currSliceType, PictureStructure currPicStructure)
{
  unsigned i;
  int j;
  int MaxFrameNum = 1 << (active_sps->log2_max_frame_num_minus4 + 4);
  int diff;

  int list0idx = 0;
  int list0idx_1 = 0;

  StorablePicture *tmp_s;

  if (currPicStructure == FRAME)
  {
    for(i=0;i<dpb.ref_frames_in_buffer; i++)
    {
      if(dpb.fs[i]->concealment_reference == 1)
      {
        if(dpb.fs[i]->frame_num > img->frame_to_conceal)
          dpb.fs_ref[i]->frame_num_wrap = dpb.fs[i]->frame_num - MaxFrameNum;
        else
          dpb.fs_ref[i]->frame_num_wrap = dpb.fs[i]->frame_num;
        dpb.fs_ref[i]->frame->pic_num = dpb.fs_ref[i]->frame_num_wrap;
      }
    }
  }

  if (currSliceType == P_SLICE)
  {
    // Calculate FrameNumWrap and PicNum
    if (currPicStructure == FRAME)
    {
      for(i=0;i<dpb.used_size; i++)
      {
        if(dpb.fs[i]->concealment_reference == 1)
        {
          listX[0][list0idx++] = dpb.fs[i]->frame;
        }
      }
      // order list 0 by PicNum
      qsort((void *)listX[0], list0idx, sizeof(StorablePicture*), compare_pic_by_pic_num_desc);
      listXsize[0] = list0idx;
    }
  }

  if (currSliceType == B_SLICE)
  {
    if (currPicStructure == FRAME)
    {
      //      for(i=0;i<dpb.ref_frames_in_buffer; i++)
      for(i=0;i<dpb.used_size; i++)
      {
        if(dpb.fs[i]->concealment_reference == 1)
        {
          if(img->earlier_missing_poc > dpb.fs[i]->frame->poc)
            listX[0][list0idx++] = dpb.fs[i]->frame;
        }
      }

      qsort((void *)listX[0], list0idx, sizeof(StorablePicture*), compare_pic_by_poc_desc);
      list0idx_1 = list0idx;

      //      for(i=0;i<dpb.ref_frames_in_buffer; i++)
      for(i=0;i<dpb.used_size; i++)
      {
        if(dpb.fs[i]->concealment_reference == 1)
        {
          if(img->earlier_missing_poc < dpb.fs[i]->frame->poc)
            listX[0][list0idx++] = dpb.fs[i]->frame;
        }
      }

      qsort((void *)&listX[0][list0idx_1], list0idx-list0idx_1, sizeof(StorablePicture*), compare_pic_by_poc_asc);

      for (j=0; j<list0idx_1; j++)
      {
        listX[1][list0idx-list0idx_1+j]=listX[0][j];
      }
      for (j=list0idx_1; j<list0idx; j++)
      {
        listX[1][j-list0idx_1]=listX[0][j];
      }

      listXsize[0] = listXsize[1] = list0idx;

      qsort((void *)&listX[0][listXsize[0]], list0idx-listXsize[0], sizeof(StorablePicture*), compare_pic_by_lt_pic_num_asc);
      qsort((void *)&listX[1][listXsize[0]], list0idx-listXsize[0], sizeof(StorablePicture*), compare_pic_by_lt_pic_num_asc);
      listXsize[0] = listXsize[1] = list0idx;
    }
  }

  if ((listXsize[0] == listXsize[1]) && (listXsize[0] > 1))
  {
    // check if lists are identical, if yes swap first two elements of listX[1]
    diff=0;
    for (j = 0; j< listXsize[0]; j++)
    {
      if (listX[0][j]!=listX[1][j])
        diff=1;
    }
    if (!diff)
    {
      tmp_s = listX[1][0];
      listX[1][0]=listX[1][1];
      listX[1][1]=tmp_s;
    }
  }


  // set max size
  listXsize[0] = imin (listXsize[0], (int)active_sps->num_ref_frames);
  listXsize[1] = imin (listXsize[1], (int)active_sps->num_ref_frames);

  listXsize[1] = 0;
  // set the unused list entries to NULL
  for (i=listXsize[0]; i< (MAX_LIST_SIZE) ; i++)
  {
    listX[0][i] = NULL;
  }
  for (i=listXsize[1]; i< (MAX_LIST_SIZE) ; i++)
  {
    listX[1][i] = NULL;
  }
}


StorablePicture *get_pic_from_dpb(int missingpoc, unsigned int *pos)
{
  int used_size = dpb.used_size - 1;
  int i, concealfrom = 0;

  if(img->conceal_mode == 1)
    concealfrom = missingpoc - img->poc_gap;
  else if (img->conceal_mode == 2)
    concealfrom = missingpoc + img->poc_gap;

  for(i = used_size; i >= 0; i--)
  {
    if(dpb.fs[i]->poc == concealfrom)
    {
      *pos = i;
      return dpb.fs[i]->frame;
    }
  }

  return NULL;
}

int comp(const void *i, const void *j)
{
  return *(int *)i - *(int *)j;
}

struct concealment_node * init_node( StorablePicture* picture, int missingpoc )
{
  struct concealment_node *ptr;

  ptr = (struct concealment_node *) calloc( 1, sizeof(struct concealment_node ) );

  if( ptr == NULL )
    return (struct concealment_node *) NULL;
  else {
    ptr->picture = picture;
    ptr->missingpocs = missingpoc;
    ptr->next = NULL;
    return ptr;
  }
}

void print_node( struct concealment_node *ptr )
{
  printf("Missing POC=%d\n", ptr->missingpocs );
}


void print_list( struct concealment_node *ptr )
{
  while( ptr != NULL )
  {
    print_node( ptr );
    ptr = ptr->next;
  }
}

void add_node( struct concealment_node *concealment_new )
{
  if( concealment_head == NULL )
  {
    concealment_end = concealment_head = concealment_new;
    return;
  }
  concealment_end->next = concealment_new;
  concealment_end = concealment_new;
}


void delete_node( struct concealment_node *ptr )
{
  // We only need to delete the first node in the linked list
  if( ptr == concealment_head ) 
  {
    concealment_head = concealment_head->next;
    if( concealment_end == ptr )
      concealment_end = concealment_end->next;
    free(ptr);
  }
}

void delete_list( struct concealment_node *ptr )
{
  struct concealment_node *temp;

  if( concealment_head == NULL ) return;

  if( ptr == concealment_head ) 
  {
    concealment_head = NULL;
    concealment_end = NULL;
  }
  else
  {
    temp = concealment_head;

    while( temp->next != ptr )
      temp = temp->next;
    concealment_end = temp;
  }

  while( ptr != NULL ) 
  {
    temp = ptr->next;
    free( ptr );
    ptr = temp;
  }
}

void conceal_non_ref_pics(int diff)
{
  int missingpoc = 0;
  unsigned int i, pos = 0;
  StorablePicture *conceal_from_picture = NULL;
  StorablePicture *conceal_to_picture = NULL;
  struct concealment_node *concealment_ptr = NULL;
  int temp_used_size = dpb.used_size;

  if(dpb.used_size == 0 )
    return;

  qsort(pocs_in_dpb, dpb.size, sizeof(int), comp);

  for(i=0;i<dpb.size-diff;i++)
  {
    dpb.used_size = dpb.size;
    if((pocs_in_dpb[i+1]-pocs_in_dpb[i])>img->poc_gap)
    {
      conceal_to_picture = alloc_storable_picture (FRAME, img->width, img->height, img->width_cr, img->height_cr);

      missingpoc = pocs_in_dpb[i] + img->poc_gap;
      // Diagnostics
      // printf("\n missingpoc = %d\n",missingpoc);

      if(missingpoc > img->earlier_missing_poc)
      {
        img->earlier_missing_poc = missingpoc;
        conceal_to_picture->top_poc= missingpoc;
        conceal_to_picture->bottom_poc=missingpoc;
        conceal_to_picture->frame_poc=missingpoc;
        conceal_to_picture->poc=missingpoc;
        conceal_from_picture = get_pic_from_dpb(missingpoc, &pos);

        assert(conceal_from_picture != NULL);

        dpb.used_size = pos+1;

        img->frame_to_conceal = conceal_from_picture->frame_num + 1;

        update_ref_list_for_concealment();
        img->conceal_slice_type = B_SLICE;
        copy_to_conceal(conceal_from_picture, conceal_to_picture, img);
        concealment_ptr = init_node( conceal_to_picture, missingpoc );
        add_node(concealment_ptr);
        // Diagnostics
        // print_node(concealment_ptr);
      }
    }
  }

  //restore the original value
  //dpb.used_size = dpb.size;
  dpb.used_size = temp_used_size;
}

void sliding_window_poc_management(StorablePicture *p)
{
  unsigned int i;

  if (dpb.used_size == dpb.size)
  {
    for(i=0;i<dpb.size-1; i++)
      pocs_in_dpb[i] = pocs_in_dpb[i+1];
  }

  //    pocs_in_dpb[dpb.used_size-1] = p->poc;
}


void write_lost_non_ref_pic(int poc, int p_out)
{
  FrameStore concealment_fs;
  if(poc > 0)
  {
    if((poc - dpb.last_output_poc) > img->poc_gap)
    {

      concealment_fs.frame = concealment_head->picture;
      concealment_fs.is_output = 0;
      concealment_fs.is_reference = 0;
      concealment_fs.is_used = 3;

      write_stored_frame(&concealment_fs, p_out);
      delete_node(concealment_head);
    }
  }
}

void write_lost_ref_after_idr(int pos)
{
  int temp = 1;

  if(last_out_fs->frame == NULL)
  {
    last_out_fs->frame = alloc_storable_picture (FRAME, img->width, img->height,
      img->width_cr, img->height_cr);
    last_out_fs->is_used = 3;
  }

  if(img->conceal_mode == 2)
  {
    temp = 2;
    img->conceal_mode = 1;
  }
  copy_to_conceal(dpb.fs[pos]->frame, last_out_fs->frame, img);

  img->conceal_mode = temp;
}

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