📄 pred.c
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/************************************************************************
*
* pred.c, part of tmn (TMN encoder)
*
************************************************************************/
#include"sim.h"
static int roundtab[] = {0,0,0,1,1,1,1,1,1,1,1,1,1,1,2,2};
/**********************************************************************
*
* Name: Predict_P
* Description: Predicts P macroblock in advanced or normal
* mode
*
* Input: pointers to current and previous frames
* and previous interpolated image,
* position and motion vector array
* Returns: pointer to MB_Structure of data to be coded
* Side effects: allocates memory to MB_Structure
*
***********************************************************************/
MB_Structure *Predict_P(PictImage *curr_image, PictImage *prev_image,
unsigned char *prev_ipol, int x, int y,
MotionVector *MV[6][MBR+1][MBC+2], int PB)
{
int m,n;
int curr[16][16];
int pred[16][16];
MotionVector *fr0,*fr1,*fr2,*fr3,*fr4;
int sum, dx, dy;
int xmb, ymb;
MB_Structure *pred_error = (MB_Structure *)malloc(sizeof(MB_Structure));
xmb = x/MB_SIZE+1;
ymb = y/MB_SIZE+1;
fr0 = MV[0][ymb][xmb];
fr1 = MV[1][ymb][xmb];
fr2 = MV[2][ymb][xmb];
fr3 = MV[3][ymb][xmb];
fr4 = MV[4][ymb][xmb];
/* Find MB in current image */
FindMB(x, y, curr_image->lum, curr);
/* Find prediction based on half pel MV */
if (advanced) {
FindPredOBMC(x, y, MV, prev_ipol, &pred[0][0], 0, PB);
FindPredOBMC(x, y, MV, prev_ipol, &pred[0][8], 1, PB);
FindPredOBMC(x, y, MV, prev_ipol, &pred[8][0], 2, PB);
FindPredOBMC(x, y, MV, prev_ipol, &pred[8][8], 3, PB);
}
else
FindPred(x, y, fr0, prev_ipol, &pred[0][0], 16, 0);
/* Do the actual prediction */
if (fr0->Mode == MODE_INTER || fr0->Mode == MODE_INTER_Q) {
for (n = 0; n < MB_SIZE; n++)
for (m = 0; m < MB_SIZE; m++)
pred_error->lum[n][m] = (int)(curr[n][m] - pred[n][m]);
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 );
DoPredChrom_P(x, y, dx, dy, curr_image, prev_image, pred_error);
}
else if (fr0->Mode == MODE_INTER4V) {
for (n = 0; n < MB_SIZE; n++)
for (m = 0; m < MB_SIZE; m++)
pred_error->lum[n][m] = (int)(curr[n][m] - pred[n][m]);
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);
DoPredChrom_P(x, y, dx, dy, curr_image, prev_image, pred_error);
}
else
fprintf(stderr,"Illegal Mode in Predict_P (pred.c)\n");
return pred_error;
}
/***********************************************************************
*
* Name: Predict_B
* Description: Predicts the B macroblock in PB-frame prediction
*
* Input: pointers to current frame, previous recon. frame,
* pos. in image, MV-data, reconstructed macroblock
* from image ahead
* Returns: pointer to differential MB data after prediction
* Side effects: allocates memory to MB_structure
*
***********************************************************************/
MB_Structure *Predict_B(PictImage *curr_image, PictImage *prev_image,
unsigned char *prev_ipol,int x, int y,
MotionVector *MV[5][MBR+1][MBC+2],
MB_Structure *recon_P, int TRD,int TRB)
{
int i,j,k;
int dx, dy, sad, sad_min=INT_MAX, curr[16][16], bdx=0, bdy=0;
MB_Structure *p_err = (MB_Structure *)malloc(sizeof(MB_Structure));
MB_Structure *pred = (MB_Structure *)malloc(sizeof(MB_Structure));
MotionVector *f[5];
int xvec, yvec, mvx, mvy;
for (k = 0; k <= 4; k++)
f[k] = MV[k][y/MB_SIZE+1][x/MB_SIZE+1];
/* Find MB in current image */
FindMB(x, y, curr_image->lum, curr);
if (f[0]->Mode == MODE_INTER4V) { /* Mode INTER4V */
/* Find forward prediction */
/* Luma */
for (j = -DEF_PBDELTA_WIN; j <= DEF_PBDELTA_WIN; j++) {
for (i = -DEF_PBDELTA_WIN; i <= DEF_PBDELTA_WIN; i++) {
FindForwLumPredPB(prev_ipol, x, y, f[1], &pred->lum[0][0],
TRD, TRB, i, j, 8, 0);
FindForwLumPredPB(prev_ipol, x, y, f[2], &pred->lum[0][8],
TRD, TRB, i, j, 8, 1);
FindForwLumPredPB(prev_ipol, x, y, f[3], &pred->lum[8][0],
TRD, TRB, i, j, 8, 2);
FindForwLumPredPB(prev_ipol, x, y, f[4], &pred->lum[8][8],
TRD, TRB, i, j, 8, 3);
sad = SAD_MB_integer(&curr[0][0],&pred->lum[0][0], 16,INT_MAX);
if (i == 0 && j == 0)
sad -= PREF_PBDELTA_NULL_VEC;
if (sad < sad_min) {
sad_min = sad;
bdx = i;
bdy = j;
}
}
}
FindForwLumPredPB(prev_ipol,x,y,f[1],&pred->lum[0][0],TRD,TRB,bdx,bdy,8,0);
FindForwLumPredPB(prev_ipol,x,y,f[2],&pred->lum[0][8],TRD,TRB,bdx,bdy,8,1);
FindForwLumPredPB(prev_ipol,x,y,f[3],&pred->lum[8][0],TRD,TRB,bdx,bdy,8,2);
FindForwLumPredPB(prev_ipol,x,y,f[4],&pred->lum[8][8],TRD,TRB,bdx,bdy,8,3);
/* chroma vectors are sum of B luma vectors divided and rounded */
xvec = yvec = 0;
for (k = 1; k <= 4; k++) {
xvec += TRB*(2*f[k]->x + f[k]->x_half)/TRD + bdx;
yvec += TRB*(2*f[k]->y + f[k]->y_half)/TRD + bdy;
}
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindChromBlock_P(x, y, dx, dy, prev_image, pred);
/* Find bidirectional prediction */
FindBiDirLumPredPB(&recon_P->lum[0][0], f[1], &pred->lum[0][0],
TRD, TRB, bdx, bdy, 0, 0);
FindBiDirLumPredPB(&recon_P->lum[0][8], f[2], &pred->lum[0][8],
TRD, TRB, bdx, bdy, 1, 0);
FindBiDirLumPredPB(&recon_P->lum[8][0], f[3], &pred->lum[8][0],
TRD, TRB, bdx, bdy, 0, 1);
FindBiDirLumPredPB(&recon_P->lum[8][8], f[4], &pred->lum[8][8],
TRD, TRB, bdx, bdy, 1, 1);
/* chroma vectors are sum of B luma vectors divided and rounded */
xvec = yvec = 0;
for (k = 1; k <= 4; k++) {
mvx = 2*f[k]->x + f[k]->x_half;
mvy = 2*f[k]->y + f[k]->y_half;
xvec += bdx == 0 ? (TRB-TRD) * mvx / TRD : TRB * mvx / TRD + bdx - mvx;
yvec += bdy == 0 ? (TRB-TRD) * mvy / TRD : TRB * mvy / TRD + bdy - mvy;
}
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindBiDirChrPredPB(recon_P, dx, dy, pred);
}
else { /* Mode INTER or INTER_Q */
/* Find forward prediction */
for (j = -DEF_PBDELTA_WIN; j <= DEF_PBDELTA_WIN; j++) {
for (i = -DEF_PBDELTA_WIN; i <= DEF_PBDELTA_WIN; i++) {
dx = i; dy = j;
/* To keep things simple I turn off PB delta vectors at the edges */
if (!mv_outside_frame) {
if (x == 0) dx = 0;
if (x == pels - MB_SIZE) dx = 0;
if (y == 0) dy = 0;
if (y == lines - MB_SIZE) dy = 0;
}
if (f[0]->Mode == MODE_INTRA || f[0]->Mode == MODE_INTRA_Q) {
dx = dy = 0;
}
if (f[0]->x == 0 && f[0]->y == 0 &&
f[0]->x_half == 0 && f[0]->y_half == 0) {
dx = dy = 0;
}
FindForwLumPredPB(prev_ipol, x, y, f[0], &pred->lum[0][0],
TRD, TRB, dx, dy, 16, 0);
sad = SAD_MB_integer(&curr[0][0],&pred->lum[0][0], 16, INT_MAX);
if (i == 0 && j == 0)
sad -= PREF_PBDELTA_NULL_VEC;
if (sad < sad_min) {
sad_min = sad;
bdx = dx;
bdy = dy;
}
}
}
FindForwLumPredPB(prev_ipol,x,y,f[0],&pred->lum[0][0],TRD,TRB,
bdx,bdy,16,0);
xvec = 4 * (TRB*(2*f[0]->x + f[0]->x_half) / TRD + bdx);
yvec = 4 * (TRB*(2*f[0]->y + f[0]->y_half) / TRD + bdy);
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindChromBlock_P(x, y, dx, dy, prev_image, pred);
/* Find bidirectional prediction */
FindBiDirLumPredPB(&recon_P->lum[0][0], f[0], &pred->lum[0][0],
TRD, TRB, bdx, bdy, 0, 0);
FindBiDirLumPredPB(&recon_P->lum[0][8], f[0], &pred->lum[0][8],
TRD, TRB, bdx, bdy, 1, 0);
FindBiDirLumPredPB(&recon_P->lum[8][0], f[0], &pred->lum[8][0],
TRD, TRB, bdx, bdy, 0, 1);
FindBiDirLumPredPB(&recon_P->lum[8][8], f[0], &pred->lum[8][8],
TRD, TRB, bdx, bdy, 1, 1);
/* chroma vectors */
mvx = 2*f[0]->x + f[0]->x_half;
xvec = bdx == 0 ? (TRB-TRD) * mvx / TRD : TRB * mvx / TRD + bdx - mvx;
xvec *= 4;
mvy = 2*f[0]->y + f[0]->y_half;
yvec = bdy == 0 ? (TRB-TRD) * mvy / TRD : TRB * mvy / TRD + bdy - mvy;
yvec *= 4;
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindBiDirChrPredPB(recon_P, dx, dy, pred);
}
/* store PB-deltas */
MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->x = bdx; /* is in half pel format */
MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->y = bdy;
MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->x_half = 0;
MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->y_half = 0;
/* Do the actual prediction */
for (j = 0; j < MB_SIZE; j++)
for (i = 0; i < MB_SIZE; i++)
p_err->lum[j][i] =
*(curr_image->lum+x+i + (y+j)*pels) - pred->lum[j][i];
y >>= 1;
x >>= 1;
for (j = 0; j < MB_SIZE>>1; j++)
for (i = 0; i < MB_SIZE>>1; i++) {
p_err->Cr[j][i] = *(curr_image->Cr+x+i + (y+j)*cpels) - pred->Cr[j][i];
p_err->Cb[j][i] = *(curr_image->Cb+x+i + (y+j)*cpels) - pred->Cb[j][i];
}
free(pred);
return p_err;
}
/***********************************************************************
*
* Name: MB_Recon_B
* Description: Reconstructs the B macroblock in PB-frame
* prediction
*
* Input: pointers previous recon. frame, pred. diff.,
* pos. in image, MV-data, reconstructed macroblock
* from image ahead
* Returns: pointer to reconstructed MB data
* Side effects: allocates memory to MB_structure
*
***********************************************************************/
MB_Structure *MB_Recon_B(PictImage *prev_image, MB_Structure *diff,
unsigned char *prev_ipol,int x, int y,
MotionVector *MV[5][MBR+1][MBC+2],
MB_Structure *recon_P,int TRD, int TRB)
{
int i,j,k;
int dx, dy, bdx, bdy, mvx, mvy, xvec, yvec;
MB_Structure *recon_B = (MB_Structure *)malloc(sizeof(MB_Structure));
MB_Structure *pred = (MB_Structure *)malloc(sizeof(MB_Structure));
MotionVector *f[5];
for (k = 0; k <= 4; k++)
f[k] = MV[k][y/MB_SIZE+1][x/MB_SIZE+1];
bdx = MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->x;
bdy = MV[5][y/MB_SIZE+1][x/MB_SIZE+1]->y;
if (f[0]->Mode == MODE_INTER4V) { /* Mode INTER4V */
/* Find forward prediction */
/* Luma */
FindForwLumPredPB(prev_ipol,x,y,f[1],&pred->lum[0][0],TRD,TRB,bdx,bdy,8,0);
FindForwLumPredPB(prev_ipol,x,y,f[2],&pred->lum[0][8],TRD,TRB,bdx,bdy,8,1);
FindForwLumPredPB(prev_ipol,x,y,f[3],&pred->lum[8][0],TRD,TRB,bdx,bdy,8,2);
FindForwLumPredPB(prev_ipol,x,y,f[4],&pred->lum[8][8],TRD,TRB,bdx,bdy,8,3);
/* chroma vectors are sum of B luma vectors divided and rounded */
xvec = yvec = 0;
for (k = 1; k <= 4; k++) {
xvec += TRB*(2*f[k]->x + f[k]->x_half)/TRD + bdx;
yvec += TRB*(2*f[k]->y + f[k]->y_half)/TRD + bdy;
}
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindChromBlock_P(x, y, dx, dy, prev_image, pred);
/* Find bidirectional prediction */
FindBiDirLumPredPB(&recon_P->lum[0][0], f[1], &pred->lum[0][0],
TRD, TRB, bdx, bdy, 0, 0);
FindBiDirLumPredPB(&recon_P->lum[0][8], f[2], &pred->lum[0][8],
TRD, TRB, bdx, bdy, 1, 0);
FindBiDirLumPredPB(&recon_P->lum[8][0], f[3], &pred->lum[8][0],
TRD, TRB, bdx, bdy, 0, 1);
FindBiDirLumPredPB(&recon_P->lum[8][8], f[4], &pred->lum[8][8],
TRD, TRB, bdx, bdy, 1, 1);
/* chroma vectors are sum of B luma vectors divided and rounded */
xvec = yvec = 0;
for (k = 1; k <= 4; k++) {
mvx = 2*f[k]->x + f[k]->x_half;
mvy = 2*f[k]->y + f[k]->y_half;
xvec += bdx == 0 ? (TRB-TRD) * mvx / TRD : TRB * mvx / TRD + bdx - mvx;
yvec += bdy == 0 ? (TRB-TRD) * mvy / TRD : TRB * mvy / TRD + bdy - mvy;
}
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindBiDirChrPredPB(recon_P, dx, dy, pred);
}
else { /* Mode INTER or INTER_Q */
/* Find forward prediction */
FindForwLumPredPB(prev_ipol,x,y,f[0],&pred->lum[0][0],TRD,TRB,
bdx,bdy,16,0);
xvec = 4 * (TRB*(2*f[0]->x + f[0]->x_half) / TRD + bdx);
yvec = 4 * (TRB*(2*f[0]->y + f[0]->y_half) / TRD + bdy);
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindChromBlock_P(x, y, dx, dy, prev_image, pred);
/* Find bidirectional prediction */
FindBiDirLumPredPB(&recon_P->lum[0][0], f[0], &pred->lum[0][0],
TRD, TRB, bdx, bdy, 0, 0);
FindBiDirLumPredPB(&recon_P->lum[0][8], f[0], &pred->lum[0][8],
TRD, TRB, bdx, bdy, 1, 0);
FindBiDirLumPredPB(&recon_P->lum[8][0], f[0], &pred->lum[8][0],
TRD, TRB, bdx, bdy, 0, 1);
FindBiDirLumPredPB(&recon_P->lum[8][8], f[0], &pred->lum[8][8],
TRD, TRB, bdx, bdy, 1, 1);
/* chroma vectors */
mvx = 2*f[0]->x + f[0]->x_half;
xvec = bdx == 0 ? (TRB-TRD) * mvx / TRD : TRB * mvx / TRD + bdx - mvx;
xvec *= 4;
mvy = 2*f[0]->y + f[0]->y_half;
yvec = bdy == 0 ? (TRB-TRD) * mvy / TRD : TRB * mvy / TRD + bdy - mvy;
yvec *= 4;
/* round values according to TABLE 16/H.263 */
dx = sign(xvec)*(roundtab[abs(xvec)%16] + (abs(xvec)/16)*2);
dy = sign(yvec)*(roundtab[abs(yvec)%16] + (abs(yvec)/16)*2);
FindBiDirChrPredPB(recon_P, dx, dy, pred);
}
/* Reconstruction */
for (j = 0; j < MB_SIZE; j++)
for (i = 0; i < MB_SIZE; i++)
recon_B->lum[j][i] = pred->lum[j][i] + diff->lum[j][i];
for (j = 0; j < MB_SIZE>>1; j++)
for (i = 0; i < MB_SIZE>>1; i++) {
recon_B->Cr[j][i] = pred->Cr[j][i] + diff->Cr[j][i];
recon_B->Cb[j][i] = pred->Cb[j][i] + diff->Cb[j][i];
}
free(pred);
return recon_B;
}
/**********************************************************************
*
* Name: FindForwLumPredPB
* Description: Finds the forward luma prediction in PB-frame
* pred.
*
* Input: pointer to prev. recon. frame, current positon,
* MV structure and pred. structure to fill
*
***********************************************************************/
void FindForwLumPredPB(unsigned char *prev_ipol, int x_curr, int y_curr,
MotionVector *fr, int *pred, int TRD, int TRB,
int bdx, int bdy, int bs, int comp)
{
int i,j;
int xvec,yvec,lx;
lx = (mv_outside_frame ? pels + (long_vectors?64:32) : pels);
/* Luma */
xvec = (TRB)*(2*fr->x + fr->x_half)/TRD + bdx;
yvec = (TRB)*(2*fr->y + fr->y_half)/TRD + bdy;
x_curr += ((comp&1)<<3);
y_curr += ((comp&2)<<2);
for (j = 0; j < bs; j++) {
for (i = 0; i < bs; i++) {
*(pred+i+j*16) = *(prev_ipol + (i+x_curr)*2 + xvec +
((j+y_curr)*2 + yvec)*lx*2);
}
}
return;
}
/**********************************************************************
*
* Name: FindBiDirLumPredPB
* Description: Finds the bi-dir. luma prediction in PB-frame
* prediction
*
* Input: pointer to future recon. data, current positon,
* MV structure and pred. structure to fill
*
***********************************************************************/
void FindBiDirLumPredPB(int *recon_P, MotionVector *fr, int *pred, int TRD,
int TRB, int bdx, int bdy, int nh, int nv)
{
int xstart,xstop,ystart,ystop;
int xvec,yvec, mvx, mvy;
mvx = 2*fr->x + fr->x_half;
mvy = 2*fr->y + fr->y_half;
xvec = (bdx == 0 ? (TRB-TRD) * mvx / TRD : TRB * mvx / TRD + bdx - mvx);
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