xir = (ri8 ? xmb : xmb+1);    /* edge handling */    if (ymb == 1) {      yit = ymb;      vect = (c8 ? 2 : 0);    }    if (xmb == pels/16) {      xir = xmb;      vecr = (c8 ? 2 : 0);    }    break;  case 3:    vect = (c8 ? 1 : 0) ; yit = ymb  ; xit = xmb;    vecb = (c8 ? 3 : 0) ; yib = ymb  ; xib = xmb;          vecl = (li8 ? (c8 ? 3 : 0) : (l8 ? 4 : 0));     yil = ymb;      xil = (li8 ? xmb : xmb-1);        vecr = (c8 ? 4 : 0) ; yir = ymb  ; xir = xmb;    /* edge handling */    if (xmb == 1) {      xil = xmb;      vecl = (c8 ? 3 : 0);    }    break;  case 4:    vect = (c8 ? 2 : 0) ; yit = ymb  ; xit = xmb;    vecb = (c8 ? 4 : 0) ; yib = ymb  ; xib = xmb;    vecl = (c8 ? 3 : 0) ; yil = ymb  ; xil = xmb;    vecr = (ri8 ? (c8 ? 4 : 0) : (r8 ? 3 : 0));     yir = ymb;     xir = (ri8 ? xmb : xmb+1);    /* edge handling */    if (xmb == pels/16) {      xir = xmb;      vecr = (c8 ? 4 : 0);    }    break;  default:    fprintf(stderr,"Illegal block number in FindPredOBMC (pred.c)\n");    exit(-1);    break;  }  fc = MV[c8 ? comp + 1: 0][ymb][xmb];  ft = MV[vect][yit][xit];  fb = MV[vecb][yib][xib];  fr = MV[vecr][yir][xir];  fl = MV[vecl][yil][xil];  nxc = 2*x + ((comp&1)<<4); nyc = 2*y + ((comp&2)<<3);  nxt = nxb = nxr = nxl = nxc;  nyt = nyb = nyr = nyl = nyc;  nxc += 2*fc->x + fc->x_half; nyc += 2*fc->y + fc->y_half;  nxt += 2*ft->x + ft->x_half; nyt += 2*ft->y + ft->y_half;  nxb += 2*fb->x + fb->x_half; nyb += 2*fb->y + fb->y_half;  nxr += 2*fr->x + fr->x_half; nyr += 2*fr->y + fr->y_half;  nxl += 2*fl->x + fl->x_half; nyl += 2*fl->y + fl->y_half;  /* Fill pred. data */  for (n = 0; n < 8; n++) {    for (m = 0; m < 8; m++) {      /* Find interpolated pixel-value */      pc = *(prev + nxc + 2*m + (nyc + 2*n)*lx*2) * Mc[n][m];      pt = *(prev + nxt + 2*m + (nyt + 2*n)*lx*2) * Mt[n][m];      pb = *(prev + nxb + 2*m + (nyb + 2*n)*lx*2) * Mb[n][m];      pr = *(prev + nxr + 2*m + (nyr + 2*n)*lx*2) * Mr[n][m];      pl = *(prev + nxl + 2*m + (nyl + 2*n)*lx*2) * Ml[n][m];      /*$pc = *(prev + nxc + 2*m + (nyc + 2*n)*lx*2) * 8;      pt = *(prev + nxt + 2*m + (nyt + 2*n)*lx*2) * 0;;      pb = *(prev + nxb + 2*m + (nyb + 2*n)*lx*2) * 0;      pr = *(prev + nxr + 2*m + (nyr + 2*n)*lx*2) * 0;      pl = *(prev + nxl + 2*m + (nyl + 2*n)*lx*2) * 0;$*/      *(pred + m + n*16) = (pc+pt+pb+pr+pl+4)>>3;    }	  }  return;}/********************************************************************** * *	Name:        ReconMacroblock_P *	Description:	Reconstructs MB after quantization for P_images *	 *	Input:        pointers to current and previous image, *        current slice and mb, and which mode *        of prediction has been used *	Returns: *	Side effects: * *	Date: 930122	Author: Karl.Lillevold@nta.no * ***********************************************************************/MB_Structure *MB_Recon_P(PictImage *prev_image, unsigned char *prev_ipol,         MB_Structure *diff, int x_curr, int y_curr,          MotionVector *MV[6][MBR+1][MBC+2], int PB){  MB_Structure *recon_data = (MB_Structure *)malloc(sizeof(MB_Structure));  MotionVector *fr0,*fr1,*fr2,*fr3,*fr4;  int pred[16][16];  int dx, dy, sum;  int i,j;  fr0 = MV[0][y_curr/MB_SIZE+1][x_curr/MB_SIZE+1];  if (advanced) {    if (fr0->Mode == MODE_INTER || fr0->Mode == MODE_INTER_Q) {      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[0][0], 0, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[0][8], 1, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[8][0], 2, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[8][8], 3, PB);      for (j = 0; j < MB_SIZE; j++)         for (i = 0; i < MB_SIZE; i++)           diff->lum[j][i] += pred[j][i];      dx = 2*fr0->x + fr0->x_half;      dy = 2*fr0->y + fr0->y_half;      dx = ( dx % 4 == 0 ? dx >> 1 : (dx>>1)|1 );      dy = ( dy % 4 == 0 ? dy >> 1 : (dy>>1)|1 );      ReconChromBlock_P(x_curr, y_curr, dx, dy, prev_image, diff);    }    else if (fr0->Mode == MODE_INTER4V) { /* Inter 8x8 */            FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[0][0], 0, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[0][8], 1, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[8][0], 2, PB);      FindPredOBMC(x_curr, y_curr, MV, prev_ipol, &pred[8][8], 3, PB);      for (j = 0; j < MB_SIZE; j++)         for (i = 0; i < MB_SIZE; i++)           diff->lum[j][i] += pred[j][i];      fr1 = MV[1][y_curr/MB_SIZE+1][x_curr/MB_SIZE+1];      fr2 = MV[2][y_curr/MB_SIZE+1][x_curr/MB_SIZE+1];      fr3 = MV[3][y_curr/MB_SIZE+1][x_curr/MB_SIZE+1];      fr4 = MV[4][y_curr/MB_SIZE+1][x_curr/MB_SIZE+1];      sum = 2*fr1->x + fr1->x_half + 2*fr2->x + fr2->x_half +        2*fr3->x + fr3->x_half + 2*fr4->x + fr4->x_half ;       dx = sign(sum)*(roundtab[abs(sum)%16] + (abs(sum)/16)*2);      sum = 2*fr1->y + fr1->y_half + 2*fr2->y + fr2->y_half +        2*fr3->y + fr3->y_half + 2*fr4->y + fr4->y_half;      dy = sign(sum)*(roundtab[abs(sum)%16] + (abs(sum)/16)*2);      ReconChromBlock_P(x_curr, y_curr, dx, dy, prev_image, diff);    }  }  else {    if (fr0->Mode == MODE_INTER || fr0->Mode == MODE_INTER_Q) {      /* Inter 16x16 */      ReconLumBlock_P(x_curr,y_curr,fr0,prev_ipol,&diff->lum[0][0],16,0);      dx = 2*fr0->x + fr0->x_half;      dy = 2*fr0->y + fr0->y_half;      dx = ( dx % 4 == 0 ? dx >> 1 : (dx>>1)|1 );      dy = ( dy % 4 == 0 ? dy >> 1 : (dy>>1)|1 );      ReconChromBlock_P(x_curr, y_curr, dx, dy, prev_image, diff);    }  }  memcpy(recon_data, diff, sizeof(MB_Structure));  return recon_data;}/********************************************************************** * *	Name:        ReconLumBlock_P *	Description:	Reconstructs one block of luminance data *	 *	Input:        position, vector-data, previous image, data-block *	Returns: *	Side effects:	reconstructs data-block * *	Date: 950210	Author: Karl.Lillevold@nta.no * ***********************************************************************/void ReconLumBlock_P(int x, int y, MotionVector *fr,              unsigned char *prev, int *data, int bs, int comp){  int m, n;  int x1, y1, lx;  lx = (mv_outside_frame ? pels + (long_vectors?64:32) : pels);  x1 = 2*(x + fr->x) + fr->x_half;  y1 = 2*(y + fr->y) + fr->y_half;    x1 += ((comp&1)<<4);  y1 += ((comp&2)<<3);  for (n = 0; n < bs; n++) {    for (m = 0; m < bs; m++) {      *(data+m+n*16) += (int)(*(prev+x1+2*m + (y1+2*n)*2*lx));    }  }  return;}/********************************************************************** * *	Name:        ReconChromBlock_P *	Description:        Reconstructs chrominance of one block in P frame *	 *	Input:        position, vector-data, previous image, data-block *	Returns:         *	Side effects:	reconstructs data-block * *	Date: 930203	Author: Karl.Lillevold@nta.no * ***********************************************************************/void ReconChromBlock_P(int x_curr, int y_curr, int dx, int dy,               PictImage *prev, MB_Structure *data){  int m,n;  int x, y, ofx, ofy, pel,lx;  int xint, yint;  int xh, yh;  lx = (mv_outside_frame ? pels/2 + (long_vectors?32:16) : pels/2);  x = x_curr>>1;  y = y_curr>>1;  xint = dx>>1;  xh = dx & 1;  yint = dy>>1;  yh = dy & 1;      if (!xh && !yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=*(prev->Cr+ofx    + (ofy   )*lx);        data->Cr[n][m] += pel;        pel=*(prev->Cb+ofx    + (ofy   )*lx);        data->Cb[n][m] += pel;      }    }  }  else if (!xh && yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx    + (ofy+yh)*lx) + 1)>>1;        data->Cr[n][m] += pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx    + (ofy+yh)*lx) + 1)>>1;        data->Cb[n][m] += pel;            }    }  }  else if (xh && !yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx+xh + (ofy   )*lx) + 1)>>1;        data->Cr[n][m] += pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx+xh + (ofy   )*lx) + 1)>>1;        data->Cb[n][m] += pel;            }    }  }  else { /* xh && yh */    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx+xh + (ofy   )*lx)+             *(prev->Cr+ofx    + (ofy+yh)*lx)+             *(prev->Cr+ofx+xh + (ofy+yh)*lx)+             2)>>2;        data->Cr[n][m] += pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx+xh + (ofy   )*lx)+             *(prev->Cb+ofx    + (ofy+yh)*lx)+             *(prev->Cb+ofx+xh + (ofy+yh)*lx)+             2)>>2;        data->Cb[n][m] += pel;            }    }  }  return;}/********************************************************************** * *	Name:        FindChromBlock_P *	Description:        Finds chrominance of one block in P frame *	 *	Input:        position, vector-data, previous image, data-block * *	Date: 950222	Author: Karl.Lillevold@nta.no * ***********************************************************************/void FindChromBlock_P(int x_curr, int y_curr, int dx, int dy,              PictImage *prev, MB_Structure *data){  int m,n;  int x, y, ofx, ofy, pel,lx;  int xint, yint;  int xh, yh;  lx = (mv_outside_frame ? pels/2 + (long_vectors?32:16) : pels/2);  x = x_curr>>1;  y = y_curr>>1;  xint = dx>>1;  xh = dx & 1;  yint = dy>>1;  yh = dy & 1;      if (!xh && !yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=*(prev->Cr+ofx    + (ofy   )*lx);        data->Cr[n][m] = pel;        pel=*(prev->Cb+ofx    + (ofy   )*lx);        data->Cb[n][m] = pel;      }    }  }  else if (!xh && yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx    + (ofy+yh)*lx) + 1)>>1;        data->Cr[n][m] = pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx    + (ofy+yh)*lx) + 1)>>1;        data->Cb[n][m] = pel;            }    }  }  else if (xh && !yh) {    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx+xh + (ofy   )*lx) + 1)>>1;        data->Cr[n][m] = pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx+xh + (ofy   )*lx) + 1)>>1;        data->Cb[n][m] = pel;            }    }  }  else { /* xh && yh */    for (n = 0; n < 8; n++) {      for (m = 0; m < 8; m++) {        ofx = x + xint + m;        ofy = y + yint + n;        pel=(*(prev->Cr+ofx    + (ofy   )*lx)+             *(prev->Cr+ofx+xh + (ofy   )*lx)+             *(prev->Cr+ofx    + (ofy+yh)*lx)+             *(prev->Cr+ofx+xh + (ofy+yh)*lx)+             2)>>2;        data->Cr[n][m] = pel;        pel=(*(prev->Cb+ofx    + (ofy   )*lx)+             *(prev->Cb+ofx+xh + (ofy   )*lx)+             *(prev->Cb+ofx    + (ofy+yh)*lx)+             *(prev->Cb+ofx+xh + (ofy+yh)*lx)+             2)>>2;        data->Cb[n][m] = pel;            }    }  }  return;}/********************************************************************** * *	Name:        ChooseMode *	Description:    chooses coding mode *	 *	Input:	        pointer to original fram, min_error from  *                      integer pel search, DQUANT *	Returns:        1 for Inter, 0 for Intra * *	Date: 941130	Author: Karl.Lillevold@nta.no * ***********************************************************************/int ChooseMode(unsigned char *curr, int x_pos, int y_pos, int min_SAD){  int i,j;  int MB_mean = 0, A = 0;  int y_off;  for (j = 0; j < MB_SIZE; j++) {    y_off = (y_pos + j) * pels;    for (i = 0; i < MB_SIZE; i++) {      MB_mean += *(curr + x_pos + i + y_off);    }  }  MB_mean /= (MB_SIZE*MB_SIZE);  for (j = 0; j < MB_SIZE; j++) {    y_off = (y_pos + j) * pels;    for (i = 0; i < MB_SIZE; i++) {      A += abs( *(curr + x_pos + i + y_off) - MB_mean );    }  }  if (A < (min_SAD - 500))     return MODE_INTRA;  else    return MODE_INTER;}int ModifyMode(int Mode, int dquant){  if (Mode == MODE_INTRA) {    if(dquant!=0)      return MODE_INTRA_Q;    else      return MODE_INTRA;  }  else{     if(dquant!=0)      return MODE_INTER_Q;    else      return Mode;  }}