if (p->imgY_11_w)
      {
        free (p->imgY_11_w);
        p->imgY_11_w=NULL;
      }
      if (p->imgY_ups_w)
      {
        free_mem2D (p->imgY_ups_w);
        p->imgY_ups_w=NULL;
      }
    }

    free(p->mb_field);

    free(p);
  }
}

/*!
 ************************************************************************
 * \brief
 *    mark FrameStore unused for reference
 *
 ************************************************************************
 */
static void unmark_for_reference(FrameStore* fs)
{

  if (!active_sps->frame_mbs_only_flag)
  {
    if (fs->is_used & 1)
    {
      fs->top_field->used_for_reference = 0;
    }
    if (fs->is_used & 2)
    {
      fs->bottom_field->used_for_reference = 0;
    }
  }

  if (fs->is_used == 3)
  {
    if (!active_sps->frame_mbs_only_flag)
    {
      fs->top_field->used_for_reference = 0;
      fs->bottom_field->used_for_reference = 0;
    }
    fs->frame->used_for_reference = 0;
  }

  fs->is_reference = 0;
}


/*!
 ************************************************************************
 * \brief
 *    mark FrameStore unused for reference and reset long term flags
 *
 ************************************************************************
 */
static void unmark_for_long_term_reference(FrameStore* fs)
{

  if (!active_sps->frame_mbs_only_flag)
  {
    if (fs->is_used & 1)
    {
      fs->top_field->used_for_reference = 0;
      fs->top_field->is_long_term = 0;
    }
    if (fs->is_used & 2)
    {
      fs->bottom_field->used_for_reference = 0;
      fs->bottom_field->is_long_term = 0;
    }
  }
  if (fs->is_used == 3)
  {
    if (!active_sps->frame_mbs_only_flag)
    {
      fs->top_field->used_for_reference = 0;
      fs->top_field->is_long_term = 0;
      fs->bottom_field->used_for_reference = 0;
      fs->bottom_field->is_long_term = 0;
    }
    fs->frame->used_for_reference = 0;
    fs->frame->is_long_term = 0;
  }
  
  fs->is_reference = 0;
  fs->is_long_term = 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by picture number for qsort in descending order
 *
 ************************************************************************
 */
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;
}

/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by picture number for qsort in descending order
 *
 ************************************************************************
 */
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;
}

/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by pic_num for qsort in descending order
 *
 ************************************************************************
 */
static int compare_fs_by_frame_num_desc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->frame_num_wrap < (*(FrameStore**)arg2)->frame_num_wrap)
    return 1;
  if ( (*(FrameStore**)arg1)->frame_num_wrap > (*(FrameStore**)arg2)->frame_num_wrap)
    return -1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by lt_pic_num for qsort in descending order
 *
 ************************************************************************
 */
static int compare_fs_by_lt_pic_idx_asc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->long_term_frame_idx < (*(FrameStore**)arg2)->long_term_frame_idx)
    return -1;
  if ( (*(FrameStore**)arg1)->long_term_frame_idx > (*(FrameStore**)arg2)->long_term_frame_idx)
    return 1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by poc for qsort in ascending order
 *
 ************************************************************************
 */
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;
}


/*!
 ************************************************************************
 * \brief
 *    compares two stored pictures by poc for qsort in descending order
 *
 ************************************************************************
 */
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;
}


/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by poc for qsort in ascending order
 *
 ************************************************************************
 */
static int compare_fs_by_poc_asc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->poc < (*(FrameStore**)arg2)->poc)
    return -1;
  if ( (*(FrameStore**)arg1)->poc > (*(FrameStore**)arg2)->poc)
    return 1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    compares two frame stores by poc for qsort in descending order
 *
 ************************************************************************
 */
static int compare_fs_by_poc_desc( const void *arg1, const void *arg2 )
{
  if ( (*(FrameStore**)arg1)->poc < (*(FrameStore**)arg2)->poc)
    return 1;
  if ( (*(FrameStore**)arg1)->poc > (*(FrameStore**)arg2)->poc)
    return -1;
  else
    return 0;
}


/*!
 ************************************************************************
 * \brief
 *    returns true, if picture is short term reference picture
 *
 ************************************************************************
 */
int is_short_ref(StorablePicture *s)
{
  return ((s->used_for_reference) && (!(s->is_long_term)));
}


/*!
 ************************************************************************
 * \brief
 *    returns true, if picture is long term reference picture
 *
 ************************************************************************
 */
int is_long_ref(StorablePicture *s)
{
  return ((s->used_for_reference) && (s->is_long_term));
}


/*!
 ************************************************************************
 * \brief
 *    Generates a alternating field list from a given FrameStore list
 *
 ************************************************************************
 */
static void gen_pic_list_from_frame_list(PictureStructure currStrcture, FrameStore **fs_list, int list_idx, StorablePicture **list, int *list_size, int long_term)
{
  int top_idx = 0;
  int bot_idx = 0;

  int (*is_ref)(StorablePicture *s);

  if (long_term)
    is_ref=is_long_ref;
  else
    is_ref=is_short_ref;

  if (currStrcture == TOP_FIELD)
  {
    while ((top_idx<list_idx)||(bot_idx<list_idx))
    {
      for ( ; top_idx<list_idx; top_idx++)
      {
        if(fs_list[top_idx]->is_used & 1)
        {
          if(is_ref(fs_list[top_idx]->top_field))
          {
            // short term ref pic
            list[*list_size] = fs_list[top_idx]->top_field;
            (*list_size)++;
            top_idx++;
            break;
          }
        }
      }
      for ( ; bot_idx<list_idx; bot_idx++)
      {
        if(fs_list[bot_idx]->is_used & 2)
        {
          if(is_ref(fs_list[bot_idx]->bottom_field))
          {
            // short term ref pic
            list[*list_size] = fs_list[bot_idx]->bottom_field;
            (*list_size)++;
            bot_idx++;
            break;
          }
        }
      }
    }
  }
  if (currStrcture == BOTTOM_FIELD)
  {
    while ((top_idx<list_idx)||(bot_idx<list_idx))
    {
      for ( ; bot_idx<list_idx; bot_idx++)
      {
        if(fs_list[bot_idx]->is_used & 2)
        {
          if(is_ref(fs_list[bot_idx]->bottom_field))
          {
            // short term ref pic
            list[*list_size] = fs_list[bot_idx]->bottom_field;
            (*list_size)++;
            bot_idx++;
            break;
          }
        }
      }
      for ( ; top_idx<list_idx; top_idx++)
      {
        if(fs_list[top_idx]->is_used & 1)
        {
          if(is_ref(fs_list[top_idx]->top_field))
          {
            // short term ref pic
            list[*list_size] = fs_list[top_idx]->top_field;
            (*list_size)++;
            top_idx++;
            break;
          }
        }
      }
    }
  }
}


/*!
 ************************************************************************
 * \brief
 *    Initialize listX[0] and list 1 depending on current picture type
 *
 ************************************************************************
 */
void init_lists(int currSliceType, PictureStructure currPicStructure)
{
  int add_top = 0, add_bottom = 0;
  unsigned i;
  int j;
  int MaxFrameNum = 1 << (log2_max_frame_num_minus4 + 4);
  int diff;

  int list0idx = 0;
  int list0idx_1 = 0;
  int listltidx = 0;

  FrameStore **fs_list0;
  FrameStore **fs_list1;
  FrameStore **fs_listlt;

  StorablePicture *tmp_s;

  if (currPicStructure == FRAME)  
  {
    for (i=0; i<dpb.ref_frames_in_buffer; i++)
    {
      if (dpb.fs_ref[i]->is_used==3)
      {
        if ((dpb.fs_ref[i]->frame->used_for_reference)&&(!dpb.fs_ref[i]->frame->is_long_term))
        {
          if( dpb.fs_ref[i]->frame_num > img->frame_num )
          {
            dpb.fs_ref[i]->frame_num_wrap = dpb.fs_ref[i]->frame_num - MaxFrameNum;
          }
          else
          {
            dpb.fs_ref[i]->frame_num_wrap = dpb.fs_ref[i]->frame_num;
          }
          dpb.fs_ref[i]->frame->pic_num = dpb.fs_ref[i]->frame_num_wrap;
          dpb.fs_ref[i]->frame->order_num=list0idx;
        }
      }
    }
  }
  else
  {
    if (currPicStructure == TOP_FIELD)
    {
      add_top    = 1;
      add_bottom = 0;
    }
    else
    {
      add_top    = 0;
      add_bottom = 1;
    }
    
    for (i=0; i<dpb.ref_frames_in_buffer; i++)
    {
      if (dpb.fs_ref[i]->is_reference)
      {
        if( dpb.fs_ref[i]->frame_num > img->frame_num )
        {
          dpb.fs_ref[i]->frame_num_wrap = dpb.fs_ref[i]->frame_num - MaxFrameNum;
        }
        else
        {
          dpb.fs_ref[i]->frame_num_wrap = dpb.fs_ref[i]->frame_num;
        }
        if (dpb.fs_ref[i]->is_reference & 1)
        {
          dpb.fs_ref[i]->top_field->pic_num = (2 * dpb.fs_ref[i]->frame_num_wrap) + add_top;
        }
        if (dpb.fs_ref[i]->is_reference & 2)
        {
          dpb.fs_ref[i]->bottom_field->pic_num = (2 * dpb.fs_ref[i]->frame_num_wrap) + add_bottom;
        }
      }
    }
  }

  if ((currSliceType == I_SLICE)||(currSliceType == SI_SLICE))
  {
    listXsize[0] = 0;
    listXsize[1] = 0;
    return;
  }

  if ((currSliceType == P_SLICE)||(currSliceType == SP_SLICE))
  {
    // Calculate FrameNumWrap and PicNum
    if (currPicStructure == FRAME)  
    {
      for (i=0; i<dpb.ref_frames_in_buffer; i++)
      {
        if (dpb.fs_ref[i]->is_used==3)
        {
          if ((dpb.fs_ref[i]->frame->used_for_reference)&&(!dpb.fs_ref[i]->frame->is_long_term))
          {
            listX[0][list0idx++] = dpb.fs_ref[i]->frame;
          }
        }
      }
      // order list 0 by PicNum
      qsort((void *)listX[0], list0idx, sizeof(StorablePicture*), compare_pic_by_pic_num_desc);
      listXsize[0] = list0idx;