/***************************************************************************** * * XVID MPEG-4 VIDEO CODEC * - Prediction module - * * Copyright (C) 2001-2003 Michael Militzer * 2001-2003 Peter Ross * * This program is free software ; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation ; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY ; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program ; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * $Id: mbprediction.c,v 1.18 2005/11/22 10:23:01 suxen_drol Exp $ * ****************************************************************************/ #include #include "../global.h" #include "../encoder.h" #include "mbprediction.h" #include "../utils/mbfunctions.h" #include "../bitstream/cbp.h" #include "../bitstream/mbcoding.h" #include "../bitstream/zigzag.h" static int __inline rescale(int predict_quant, int current_quant, int coeff) { return (coeff != 0) ? DIV_DIV((coeff) * (predict_quant), (current_quant)) : 0; } static const int16_t default_acdc_values[15] = { 1024, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* get dc/ac prediction direction for a single block and place predictor values into MB->pred_values[j][..] */ void predict_acdc(MACROBLOCK * pMBs, uint32_t x, uint32_t y, uint32_t mb_width, uint32_t block, int16_t qcoeff[64], uint32_t current_quant, int32_t iDcScaler, int16_t predictors[8], const int bound) { const int mbpos = (y * mb_width) + x; int16_t *left, *top, *diag, *current; int32_t left_quant = current_quant; int32_t top_quant = current_quant; const int16_t *pLeft = default_acdc_values; const int16_t *pTop = default_acdc_values; const int16_t *pDiag = default_acdc_values; uint32_t index = x + y * mb_width; /* current macroblock */ int *acpred_direction = &pMBs[index].acpred_directions[block]; uint32_t i; left = top = diag = current = NULL; /* grab left,top and diag macroblocks */ /* left macroblock */ if (x && mbpos >= bound + 1 && (pMBs[index - 1].mode == MODE_INTRA || pMBs[index - 1].mode == MODE_INTRA_Q)) { left = (int16_t*)pMBs[index - 1].pred_values[0]; left_quant = pMBs[index - 1].quant; } /* top macroblock */ if (mbpos >= bound + (int)mb_width && (pMBs[index - mb_width].mode == MODE_INTRA || pMBs[index - mb_width].mode == MODE_INTRA_Q)) { top = (int16_t*)pMBs[index - mb_width].pred_values[0]; top_quant = pMBs[index - mb_width].quant; } /* diag macroblock */ if (x && mbpos >= bound + (int)mb_width + 1 && (pMBs[index - 1 - mb_width].mode == MODE_INTRA || pMBs[index - 1 - mb_width].mode == MODE_INTRA_Q)) { diag = (int16_t*)pMBs[index - 1 - mb_width].pred_values[0]; } current = (int16_t*)pMBs[index].pred_values[0]; /* now grab pLeft, pTop, pDiag _blocks_ */ switch (block) { case 0: if (left) pLeft = left + MBPRED_SIZE; if (top) pTop = top + (MBPRED_SIZE << 1); if (diag) pDiag = diag + 3 * MBPRED_SIZE; break; case 1: pLeft = current; left_quant = current_quant; if (top) { pTop = top + 3 * MBPRED_SIZE; pDiag = top + (MBPRED_SIZE << 1); } break; case 2: if (left) { pLeft = left + 3 * MBPRED_SIZE; pDiag = left + MBPRED_SIZE; } pTop = current; top_quant = current_quant; break; case 3: pLeft = current + (MBPRED_SIZE << 1); left_quant = current_quant; pTop = current + MBPRED_SIZE; top_quant = current_quant; pDiag = current; break; case 4: if (left) pLeft = left + (MBPRED_SIZE << 2); if (top) pTop = top + (MBPRED_SIZE << 2); if (diag) pDiag = diag + (MBPRED_SIZE << 2); break; case 5: if (left) pLeft = left + 5 * MBPRED_SIZE; if (top) pTop = top + 5 * MBPRED_SIZE; if (diag) pDiag = diag + 5 * MBPRED_SIZE; break; } /* determine ac prediction direction & ac/dc predictor place rescaled ac/dc * predictions into predictors[] for later use */ if (abs(pLeft[0] - pDiag[0]) < abs(pDiag[0] - pTop[0])) { *acpred_direction = 1; /* vertical */ predictors[0] = DIV_DIV(pTop[0], iDcScaler); for (i = 1; i < 8; i++) { predictors[i] = rescale(top_quant, current_quant, pTop[i]); } } else { *acpred_direction = 2; /* horizontal */ predictors[0] = DIV_DIV(pLeft[0], iDcScaler); for (i = 1; i < 8; i++) { predictors[i] = rescale(left_quant, current_quant, pLeft[i + 7]); } } } /* decoder: add predictors to dct_codes[] and store current coeffs to pred_values[] for future prediction */ /* Up to this version, no DC clipping was performed, so we try to be backward * compatible to avoid artifacts */ #define BS_VERSION_BUGGY_DC_CLIPPING 34 void add_acdc(MACROBLOCK * pMB, uint32_t block, int16_t dct_codes[64], uint32_t iDcScaler, int16_t predictors[8], const int bsversion) { uint8_t acpred_direction = pMB->acpred_directions[block]; int16_t *pCurrent = (int16_t*)pMB->pred_values[block]; uint32_t i; DPRINTF(XVID_DEBUG_COEFF,"predictor[0] %i\n", predictors[0]); dct_codes[0] += predictors[0]; /* dc prediction */ pCurrent[0] = dct_codes[0]*iDcScaler; if (!bsversion || bsversion > BS_VERSION_BUGGY_DC_CLIPPING) { pCurrent[0] = CLIP(pCurrent[0], -2048, 2047); } if (acpred_direction == 1) { for (i = 1; i < 8; i++) { int level = dct_codes[i] + predictors[i]; DPRINTF(XVID_DEBUG_COEFF,"predictor[%i] %i\n",i, predictors[i]); dct_codes[i] = level; pCurrent[i] = level; pCurrent[i + 7] = dct_codes[i * 8]; } } else if (acpred_direction == 2) { for (i = 1; i < 8; i++) { int level = dct_codes[i * 8] + predictors[i]; DPRINTF(XVID_DEBUG_COEFF,"predictor[%i] %i\n",i*8, predictors[i]); dct_codes[i * 8] = level; pCurrent[i + 7] = level; pCurrent[i] = dct_codes[i]; } } else { for (i = 1; i < 8; i++) { pCurrent[i] = dct_codes[i]; pCurrent[i + 7] = dct_codes[i * 8]; } } } /***************************************************************************** ****************************************************************************/ /* encoder: subtract predictors from qcoeff[] and calculate S1/S2 returns sum of coeefficients *saved* if prediction is enabled S1 = sum of all (qcoeff - prediction) S2 = sum of all qcoeff */ static int calc_acdc_coeff(MACROBLOCK * pMB, uint32_t block, int16_t qcoeff[64], uint32_t iDcScaler, int16_t predictors[8]) { int16_t *pCurrent = (int16_t*)pMB->pred_values[block]; uint32_t i; int S1 = 0, S2 = 0; /* store current coeffs to pred_values[] for future prediction */ pCurrent[0] = qcoeff[0] * iDcScaler; pCurrent[0] = CLIP(pCurrent[0], -2048, 2047); for (i = 1; i < 8; i++) { pCurrent[i] = qcoeff[i]; pCurrent[i + 7] = qcoeff[i * 8]; } /* subtract predictors and store back in predictors[] */ qcoeff[0] = qcoeff[0] - predictors[0]; if (pMB->acpred_directions[block] == 1) { for (i = 1; i < 8; i++) { int16_t level; level = qcoeff[i]; S2 += abs(level); level -= predictors[i]; S1 += abs(level); predictors[i] = level; } } else /* acpred_direction == 2 */ { for (i = 1; i < 8; i++) { int16_t level; level = qcoeff[i * 8]; S2 += abs(level); level -= predictors[i]; S1 += abs(level); predictors[i] = level; } } return S2 - S1; } /* returns the bits *saved* if prediction is enabled */ static int calc_acdc_bits(MACROBLOCK * pMB, uint32_t block, int16_t qcoeff[64], uint32_t iDcScaler, int16_t predictors[8]) { const int direction = pMB->acpred_directions[block]; int16_t *pCurrent = (int16_t*)pMB->pred_values[block]; int16_t tmp[8]; unsigned int i; int Z1, Z2; /* store current coeffs to pred_values[] for future prediction */ pCurrent[0] = qcoeff[0] * iDcScaler; pCurrent[0] = CLIP(pCurrent[0], -2048, 2047); for (i = 1; i < 8; i++) { pCurrent[i] = qcoeff[i]; pCurrent[i + 7] = qcoeff[i * 8]; } /* dc prediction */ qcoeff[0] = qcoeff[0] - predictors[0]; /* calc cost before ac prediction */ Z2 = CodeCoeffIntra_CalcBits(qcoeff, scan_tables[0]); /* apply ac prediction & calc cost*/ if (direction == 1) { for (i = 1; i < 8; i++) { tmp[i] = qcoeff[i]; qcoeff[i] -= predictors[i]; predictors[i] = qcoeff[i]; } }else{ /* acpred_direction == 2 */ for (i = 1; i < 8; i++) { tmp[i] = qcoeff[i*8]; qcoeff[i*8] -= predictors[i]; predictors[i] = qcoeff[i*8]; } } Z1 = CodeCoeffIntra_CalcBits(qcoeff, scan_tables[direction]); /* undo prediction */ if (direction == 1) { for (i = 1; i < 8; i++) qcoeff[i] = tmp[i]; }else{ /* acpred_direction == 2 */ for (i = 1; i < 8; i++) qcoeff[i*8] = tmp[i]; } return Z2-Z1; } /* apply predictors[] to qcoeff */ static void apply_acdc(MACROBLOCK * pMB, uint32_t block, int16_t qcoeff[64], int16_t predictors[8]) { unsigned int i; if (pMB->acpred_directions[block] == 1) { for (i = 1; i < 8; i++) qcoeff[i] = predictors[i]; } else { for (i = 1; i < 8; i++) qcoeff[i * 8] = predictors[i]; } } void MBPrediction(FRAMEINFO * frame, uint32_t x, uint32_t y, uint32_t mb_width, int16_t qcoeff[6 * 64]) { int32_t j; int32_t iDcScaler, iQuant; int S = 0; int16_t predictors[6][8]; MACROBLOCK *pMB = &frame->mbs[x + y * mb_width]; iQuant = pMB->quant; if ((pMB->mode == MODE_INTRA) || (pMB->mode == MODE_INTRA_Q)) { for (j = 0; j < 6; j++) { iDcScaler = get_dc_scaler(iQuant, j<4); predict_acdc(frame->mbs, x, y, mb_width, j, &qcoeff[j * 64], iQuant, iDcScaler, predictors[j], 0); if ((frame->vop_flags & XVID_VOP_HQACPRED)) S += calc_acdc_bits(pMB, j, &qcoeff[j * 64], iDcScaler, predictors[j]); else S += calc_acdc_coeff(pMB, j, &qcoeff[j * 64], iDcScaler, predictors[j]); } if (S<=0) { /* dont predict */ for (j = 0; j < 6; j++) pMB->acpred_directions[j] = 0; }else{ for (j = 0; j < 6; j++) apply_acdc(pMB, j, &qcoeff[j * 64], predictors[j]); } pMB->cbp = calc_cbp(qcoeff); } } static const VECTOR zeroMV = { 0, 0 }; VECTOR get_pmv2(const MACROBLOCK * const mbs, const int mb_width, const int bound, const int x, const int y, const int block) { int lx, ly, lz; /* left */ int tx, ty, tz; /* top */ int rx, ry, rz; /* top-right */ int lpos, tpos, rpos; int num_cand = 0, last_cand = 1; VECTOR pmv[4]; /* left neighbour, top neighbour, top-right neighbour */ switch (block) { case 0: lx = x - 1; ly = y; lz = 1; tx = x; ty = y - 1; tz = 2; rx = x + 1; ry = y - 1; rz = 2; break; case 1: lx = x; ly = y; lz = 0; tx = x; ty = y - 1; tz = 3; rx = x + 1; ry = y - 1; rz = 2; break; case 2: lx = x - 1; ly = y; lz = 3; tx = x; ty = y; tz = 0; rx = x; ry = y; rz = 1; break; default: lx = x; ly = y; lz = 2; tx = x; ty = y; tz = 0; rx = x; ry = y; rz = 1; } lpos = lx + ly * mb_width; rpos = rx + ry * mb_width; tpos = tx + ty * mb_width; if (lpos >= bound && lx >= 0) { num_cand++; pmv[1] = mbs[lpos].mvs[lz]; } else pmv[1] = zeroMV; if (tpos >= bound) { num_cand++; last_cand = 2; pmv[2] = mbs[tpos].mvs[tz]; } else pmv[2] = zeroMV; if (rpos >= bound && rx < mb_width) { num_cand++; last_cand = 3; pmv[3] = mbs[rpos].mvs[rz]; } else pmv[3] = zeroMV; /* If there're more than one candidate, we return the median vector */ if (num_cand > 1) { /* set median */ pmv[0].x = MIN(MAX(pmv[1].x, pmv[2].x), MIN(MAX(pmv[2].x, pmv[3].x), MAX(pmv[1].x, pmv[3].x))); pmv[0].y = MIN(MAX(pmv[1].y, pmv[2].y), MIN(MAX(pmv[2].y, pmv[3].y), MAX(pmv[1].y, pmv[3].y))); return pmv[0]; } return pmv[last_cand]; /* no point calculating median mv */ } VECTOR get_pmv2_interlaced(const MACROBLOCK * const mbs, const int mb_width, const int bound, const int x, const int y, const int block) { int lx, ly, lz; /* left */ int tx, ty, tz; /* top */ int rx, ry, rz; /* top-right */ int lpos, tpos, rpos; int num_cand = 0, last_cand = 1; VECTOR pmv[4]; /* left neighbour, top neighbour, top-right neighbour */ lx=x-1; ly=y; lz=1; tx=x; ty=y-1; tz=2; rx=x+1; ry=y-1; rz=2; lpos=lx+ly*mb_width; rpos=rx+ry*mb_width; tpos=tx+ty*mb_width; if(lx>=0 && lpos>=bound) { num_cand++; if(mbs[lpos].field_pred) pmv[1] = mbs[lpos].mvs_avg; else pmv[1] = mbs[lpos].mvs[lz]; } else { pmv[1] = zeroMV; } if(tpos>=bound) { num_cand++; last_cand=2; if(mbs[tpos].field_pred) pmv[2] = mbs[tpos].mvs_avg; else pmv[2] = mbs[tpos].mvs[tz]; } else { pmv[2] = zeroMV; } if(rx=bound) { num_cand++; last_cand = 3; if(mbs[rpos].field_pred) pmv[3] = mbs[rpos].mvs_avg; else pmv[3] = mbs[rpos].mvs[rz]; } else { pmv[3] = zeroMV; } /* If there're more than one candidate, we return the median vector */ if(num_cand>1) { /* set median */ pmv[0].x = MIN(MAX(pmv[1].x, pmv[2].x), MIN(MAX(pmv[2].x, pmv[3].x), MAX(pmv[1].x, pmv[3].x))); pmv[0].y = MIN(MAX(pmv[1].y, pmv[2].y), MIN(MAX(pmv[2].y, pmv[3].y), MAX(pmv[1].y, pmv[3].y))); return pmv[0]; } return pmv[last_cand]; /* no point calculating median mv */ } VECTOR get_qpmv2(const MACROBLOCK * const mbs, const int mb_width, const int bound, const int x, const int y, const int block) { int lx, ly, lz; /* left */ int tx, ty, tz; /* top */ int rx, ry, rz; /* top-right */ int lpos, tpos, rpos; int num_cand = 0, last_cand = 1; VECTOR pmv[4]; /* left neighbour, top neighbour, top-right neighbour */ switch (block) { case 0: lx = x - 1; ly = y; lz = 1; tx = x; ty = y - 1; tz = 2; rx = x + 1; ry = y - 1; rz = 2; break; case 1: lx = x; ly = y; lz = 0; tx = x; ty = y - 1; tz = 3; rx = x + 1; ry = y - 1; rz = 2; break; case 2: lx = x - 1; ly = y; lz = 3; tx = x; ty = y; tz = 0; rx = x; ry = y; rz = 1; break; default: lx = x; ly = y; lz = 2; tx = x; ty = y; tz = 0; rx = x; ry = y; rz = 1; } lpos = lx + ly * mb_width; rpos = rx + ry * mb_width; tpos = tx + ty * mb_width; if (lpos >= bound && lx >= 0) { num_cand++; pmv[1] = mbs[lpos].qmvs[lz]; } else pmv[1] = zeroMV; if (tpos >= bound) { num_cand++; last_cand = 2; pmv[2] = mbs[tpos].qmvs[tz]; } else pmv[2] = zeroMV; if (rpos >= bound && rx < mb_width) { num_cand++; last_cand = 3; pmv[3] = mbs[rpos].qmvs[rz]; } else pmv[3] = zeroMV; /* If there're more than one candidate, we return the median vector */ if (num_cand > 1) { /* set median */ pmv[0].x = MIN(MAX(pmv[1].x, pmv[2].x), MIN(MAX(pmv[2].x, pmv[3].x), MAX(pmv[1].x, pmv[3].x))); pmv[0].y = MIN(MAX(pmv[1].y, pmv[2].y), MIN(MAX(pmv[2].y, pmv[3].y), MAX(pmv[1].y, pmv[3].y))); return pmv[0]; } return pmv[last_cand]; /* no point calculating median mv */ }