encoder.c

mpeg4代码,比较具体

		} else {
			pFrame->intra = FrameCodeP(pEnc, &bs, &bits, 0, write_vol_header);
		}
	} else {
		if (pFrame->intra == 1) {
			pFrame->intra = FrameCodeI(pEnc, &bs, &bits);
		} else {
			pFrame->intra = FrameCodeP(pEnc, &bs, &bits, 1, write_vol_header);
		}

	}

	/* Fix from CVS_HEAD (2003-03-17)
	 *
	 * Relic from OpenDivX - now disabled
	 *
	 * BitstreamPutBits(&bs, 0xFFFF, 16);
	 * BitstreamPutBits(&bs, 0xFFFF, 16);
	 */
	BitstreamPadAlways(&bs); /* next_start_code() at the end of Video Object Plane */
	pFrame->length = BitstreamLength(&bs);

	if (pResult) {
		pResult->quant = pEnc->current->quant;
		pResult->hlength = pFrame->length - (pEnc->sStat.iTextBits / 8);
		pResult->kblks = pEnc->sStat.kblks;
		pResult->mblks = pEnc->sStat.mblks;
		pResult->ublks = pEnc->sStat.ublks;
	}

	emms();

	if (pFrame->quant == 0) {
		RateControlUpdate(&pEnc->rate_control, (int16_t)pEnc->current->quant,
						  pFrame->length, pFrame->intra);
	}
#ifdef _DEBUG_PSNR
	psnr =
		image_psnr(&pEnc->sOriginal, &pEnc->current->image,
				   pEnc->mbParam.edged_width, pEnc->mbParam.width,
				   pEnc->mbParam.height);

	snprintf(temp, 127, "PSNR: %f\n", psnr);
	DEBUG(temp);
#endif

	inc_frame_num(pEnc);
	pEnc->iFrameNum++;

	stop_global_timer();
	write_timer();

	return XVID_ERR_OK;
}


static __inline void
CodeIntraMB(Encoder * pEnc,
			MACROBLOCK * pMB)
{

	pMB->mode = MODE_INTRA;

	/* zero mv statistics */
	pMB->mvs[0].x = pMB->mvs[1].x = pMB->mvs[2].x = pMB->mvs[3].x = 0;
	pMB->mvs[0].y = pMB->mvs[1].y = pMB->mvs[2].y = pMB->mvs[3].y = 0;
	pMB->sad8[0] = pMB->sad8[1] = pMB->sad8[2] = pMB->sad8[3] = 0;
	pMB->sad16 = 0;

	if ((pEnc->current->global_flags & XVID_LUMIMASKING)) {
		if (pMB->dquant != NO_CHANGE) {
			pMB->mode = MODE_INTRA_Q;
			pEnc->current->quant += DQtab[pMB->dquant];

			if (pEnc->current->quant > 31)
				pEnc->current->quant = 31;
			if (pEnc->current->quant < 1)
				pEnc->current->quant = 1;
		}
	}

	pMB->quant = pEnc->current->quant;
}


#define FCODEBITS	3
#define MODEBITS	5

void
HintedMESet(Encoder * pEnc,
			int *intra)
{
	HINTINFO *hint;
	Bitstream bs;
	int length, high;
	uint32_t x, y;

	hint = pEnc->mbParam.hint;

	if (hint->rawhints) {
		*intra = hint->mvhint.intra;
	} else {
		BitstreamInit(&bs, hint->hintstream, hint->hintlength);
		*intra = BitstreamGetBit(&bs);
	}

	if (*intra) {
		return;
	}

	pEnc->current->fcode = (hint->rawhints != 0) ?
		(uint32_t)hint->mvhint.fcode : BitstreamGetBits(&bs, FCODEBITS);

	length = pEnc->current->fcode + 5;
	high = 1 << (length - 1);

	for (y = 0; y < pEnc->mbParam.mb_height; ++y) {
		for (x = 0; x < pEnc->mbParam.mb_width; ++x) {
			MACROBLOCK *pMB =
				&pEnc->current->mbs[x + y * pEnc->mbParam.mb_width];
			MVBLOCKHINT *bhint =
				&hint->mvhint.block[x + y * pEnc->mbParam.mb_width];
			VECTOR pred;
			VECTOR tmp;
			int vec;

			pMB->mode = (hint->rawhints != 0) ?
				(uint32_t)bhint->mode : BitstreamGetBits(&bs, MODEBITS);

			pMB->mode = (pMB->mode == MODE_INTER_Q) ? MODE_INTER : pMB->mode;
			pMB->mode = (pMB->mode == MODE_INTRA_Q) ? MODE_INTRA : pMB->mode;

			if (pMB->mode == MODE_INTER) {
				tmp.x = (hint->rawhints) ?
					bhint->mvs[0].x : (int)BitstreamGetBits(&bs, length);
				tmp.y =	(hint->rawhints) ?
					bhint->mvs[0].y : (int)BitstreamGetBits(&bs, length);
				tmp.x -= (tmp.x >= high) ? high * 2 : 0;
				tmp.y -= (tmp.y >= high) ? high * 2 : 0;

				pred = get_pmv2(pEnc->current->mbs,pEnc->mbParam.mb_width,0,x,y,0);

				for (vec = 0; vec < 4; ++vec) {
					pMB->mvs[vec].x = tmp.x;
					pMB->mvs[vec].y = tmp.y;
					pMB->pmvs[vec].x = pMB->mvs[0].x - pred.x;
					pMB->pmvs[vec].y = pMB->mvs[0].y - pred.y;
				}
			} else if (pMB->mode == MODE_INTER4V) {
				for (vec = 0; vec < 4; ++vec) {
					tmp.x = (hint->rawhints) ?
						bhint->mvs[vec].x : (int)BitstreamGetBits(&bs, length);
					tmp.y = (hint->rawhints) ?
						bhint->mvs[vec].y : (int)BitstreamGetBits(&bs, length);
					tmp.x -= (tmp.x >= high) ? high * 2 : 0;
					tmp.y -= (tmp.y >= high) ? high * 2 : 0;

					pred = get_pmv2(pEnc->current->mbs,pEnc->mbParam.mb_width,0,x,y,vec);

					pMB->mvs[vec].x = tmp.x;
					pMB->mvs[vec].y = tmp.y;
					pMB->pmvs[vec].x = pMB->mvs[vec].x - pred.x;
					pMB->pmvs[vec].y = pMB->mvs[vec].y - pred.y;
				}
			} else				/* intra / stuffing / not_coded */
			{
				for (vec = 0; vec < 4; ++vec) {
					pMB->mvs[vec].x = pMB->mvs[vec].y = 0;
				}
			}

			if (pMB->mode == MODE_INTER4V &&
				(pEnc->current->global_flags & XVID_LUMIMASKING)
				&& pMB->dquant != NO_CHANGE) {
				pMB->mode = MODE_INTRA;

				for (vec = 0; vec < 4; ++vec) {
					pMB->mvs[vec].x = pMB->mvs[vec].y = 0;
				}
			}
		}
	}
}


void
HintedMEGet(Encoder * pEnc,
			int intra)
{
	HINTINFO *hint;
	Bitstream bs;
	uint32_t x, y;
	int length, high;

	hint = pEnc->mbParam.hint;

	if (hint->rawhints) {
		hint->mvhint.intra = intra;
	} else {
		BitstreamInit(&bs, hint->hintstream, 0);
		BitstreamPutBit(&bs, intra);
	}

	if (intra) {
		if (!hint->rawhints) {
			BitstreamPad(&bs);
			hint->hintlength = BitstreamLength(&bs);
		}
		return;
	}

	length = pEnc->current->fcode + 5;
	high = 1 << (length - 1);

	if (hint->rawhints) {
		hint->mvhint.fcode = pEnc->current->fcode;
	} else {
		BitstreamPutBits(&bs, pEnc->current->fcode, FCODEBITS);
	}

	for (y = 0; y < pEnc->mbParam.mb_height; ++y) {
		for (x = 0; x < pEnc->mbParam.mb_width; ++x) {
			MACROBLOCK *pMB =
				&pEnc->current->mbs[x + y * pEnc->mbParam.mb_width];
			MVBLOCKHINT *bhint =
				&hint->mvhint.block[x + y * pEnc->mbParam.mb_width];
			VECTOR tmp;

			if (hint->rawhints) {
				bhint->mode = pMB->mode;
			} else {
				BitstreamPutBits(&bs, pMB->mode, MODEBITS);
			}

			if (pMB->mode == MODE_INTER || pMB->mode == MODE_INTER_Q) {
				tmp.x = pMB->mvs[0].x;
				tmp.y = pMB->mvs[0].y;
				tmp.x += (tmp.x < 0) ? high * 2 : 0;
				tmp.y += (tmp.y < 0) ? high * 2 : 0;

				if (hint->rawhints) {
					bhint->mvs[0].x = tmp.x;
					bhint->mvs[0].y = tmp.y;
				} else {
					BitstreamPutBits(&bs, tmp.x, length);
					BitstreamPutBits(&bs, tmp.y, length);
				}
			} else if (pMB->mode == MODE_INTER4V) {
				int vec;

				for (vec = 0; vec < 4; ++vec) {
					tmp.x = pMB->mvs[vec].x;
					tmp.y = pMB->mvs[vec].y;
					tmp.x += (tmp.x < 0) ? high * 2 : 0;
					tmp.y += (tmp.y < 0) ? high * 2 : 0;

					if (hint->rawhints) {
						bhint->mvs[vec].x = tmp.x;
						bhint->mvs[vec].y = tmp.y;
					} else {
						BitstreamPutBits(&bs, tmp.x, length);
						BitstreamPutBits(&bs, tmp.y, length);
					}
				}
			}
		}
	}

	if (!hint->rawhints) {
		BitstreamPad(&bs);
		hint->hintlength = BitstreamLength(&bs);
	}
}


static int
FrameCodeI(Encoder * pEnc,
		   Bitstream * bs,
		   uint32_t * pBits)
{

	DECLARE_ALIGNED_MATRIX(dct_codes, 6, 64, int16_t, CACHE_LINE);
	DECLARE_ALIGNED_MATRIX(qcoeff, 6, 64, int16_t, CACHE_LINE);

	uint16_t x, y;

	pEnc->iFrameNum = 0;
	pEnc->mbParam.m_rounding_type = 1;
	pEnc->current->rounding_type = pEnc->mbParam.m_rounding_type;
	pEnc->current->coding_type = I_VOP;

	BitstreamWriteVolHeader(bs, &pEnc->mbParam, pEnc->current);

	BitstreamWriteVopHeader(bs, &pEnc->mbParam, pEnc->current, 1);

	*pBits = BitstreamPos(bs);

	pEnc->sStat.iTextBits = 0;
	pEnc->sStat.kblks = pEnc->mbParam.mb_width * pEnc->mbParam.mb_height;
	pEnc->sStat.mblks = pEnc->sStat.ublks = 0;

	for (y = 0; y < pEnc->mbParam.mb_height; y++)
		for (x = 0; x < pEnc->mbParam.mb_width; x++) {
			MACROBLOCK *pMB =
				&pEnc->current->mbs[x + y * pEnc->mbParam.mb_width];

			CodeIntraMB(pEnc, pMB);

			MBTransQuantIntra(&pEnc->mbParam, pEnc->current, pMB, x, y,
							  dct_codes, qcoeff);

			start_timer();
			MBPrediction(pEnc->current, x, y, pEnc->mbParam.mb_width, qcoeff);
			stop_prediction_timer();

			start_timer();
			if (pEnc->current->global_flags & XVID_GREYSCALE)
			{	pMB->cbp &= 0x3C;		/* keep only bits 5-2 */
				qcoeff[4*64+0]=0;		/* zero, because for INTRA MBs DC value is saved */
				qcoeff[5*64+0]=0;
			}
			MBCoding(pEnc->current, pMB, qcoeff, bs, &pEnc->sStat);
			stop_coding_timer();
		}

	emms();

	*pBits = BitstreamPos(bs) - *pBits;
	pEnc->sStat.fMvPrevSigma = -1;
	pEnc->sStat.iMvSum = 0;
	pEnc->sStat.iMvCount = 0;
	pEnc->mbParam.m_fcode = 2;

	if (pEnc->current->global_flags & XVID_HINTEDME_GET) {
		HintedMEGet(pEnc, 1);
	}

	return 1;					/* intra */
}


#define INTRA_THRESHOLD 0.5

static int
FrameCodeP(Encoder * pEnc,
		   Bitstream * bs,
		   uint32_t * pBits,
		   bool force_inter,
		   bool vol_header)
{
	float fSigma;

	DECLARE_ALIGNED_MATRIX(dct_codes, 6, 64, int16_t, CACHE_LINE);
	DECLARE_ALIGNED_MATRIX(qcoeff, 6, 64, int16_t, CACHE_LINE);

	int iLimit;
	unsigned int x, y;
	int iSearchRange;
	int bIntra;
	
	/* IMAGE *pCurrent = &pEnc->current->image; */
	IMAGE *pRef = &pEnc->reference->image;

	start_timer();
	image_setedges(pRef, pEnc->mbParam.edged_width, pEnc->mbParam.edged_height,
				   pEnc->mbParam.width, pEnc->mbParam.height);
	stop_edges_timer();

	pEnc->mbParam.m_rounding_type = 1 - pEnc->mbParam.m_rounding_type;
	pEnc->current->rounding_type = pEnc->mbParam.m_rounding_type;
	pEnc->current->fcode = pEnc->mbParam.m_fcode;

	if (!force_inter)
		iLimit =
			(int) (pEnc->mbParam.mb_width * pEnc->mbParam.mb_height *
				   INTRA_THRESHOLD);
	else
		iLimit = pEnc->mbParam.mb_width * pEnc->mbParam.mb_height + 1;

	if ((pEnc->current->global_flags & XVID_HALFPEL)) {
		start_timer();
		image_interpolate(pRef, &pEnc->vInterH, &pEnc->vInterV,
						  &pEnc->vInterHV, pEnc->mbParam.edged_width,
						  pEnc->mbParam.edged_height,
						  pEnc->current->rounding_type);
		stop_inter_timer();
	}

	start_timer();
	if (pEnc->current->global_flags & XVID_HINTEDME_SET) {
		HintedMESet(pEnc, &bIntra);
	} else {

		bIntra =
			MotionEstimation(&pEnc->mbParam, pEnc->current, pEnc->reference,
                         &pEnc->vInterH, &pEnc->vInterV, &pEnc->vInterHV,
                         iLimit);
			
	}
	stop_motion_timer();

	if (bIntra == 1) {
		return FrameCodeI(pEnc, bs, pBits);
	}

	pEnc->current->coding_type = P_VOP;

	if (vol_header)
		BitstreamWriteVolHeader(bs, &pEnc->mbParam, pEnc->current);

	BitstreamWriteVopHeader(bs, &pEnc->mbParam, pEnc->current, 1);

	*pBits = BitstreamPos(bs);

	pEnc->sStat.iTextBits = 0;
	pEnc->sStat.iMvSum = 0;
	pEnc->sStat.iMvCount = 0;
	pEnc->sStat.kblks = pEnc->sStat.mblks = pEnc->sStat.ublks = 0;

	for (y = 0; y < pEnc->mbParam.mb_height; y++) {
		for (x = 0; x < pEnc->mbParam.mb_width; x++) {
			MACROBLOCK *pMB =
				&pEnc->current->mbs[x + y * pEnc->mbParam.mb_width];

			bIntra = (pMB->mode == MODE_INTRA) || (pMB->mode == MODE_INTRA_Q);

			if (!bIntra) {
				start_timer();
				MBMotionCompensation(pMB, x, y, &pEnc->reference->image,
									 &pEnc->vInterH, &pEnc->vInterV,
									 &pEnc->vInterHV, &pEnc->current->image,
									 dct_codes, pEnc->mbParam.width,
									 pEnc->mbParam.height,
									 pEnc->mbParam.edged_width,
									 pEnc->current->rounding_type);
				stop_comp_timer();

				if ((pEnc->current->global_flags & XVID_LUMIMASKING)) {
					if (pMB->dquant != NO_CHANGE) {
						pMB->mode = MODE_INTER_Q;
						pEnc->current->quant += DQtab[pMB->dquant];
						if (pEnc->current->quant > 31)
							pEnc->current->quant = 31;
						else if (pEnc->current->quant < 1)
							pEnc->current->quant = 1;
					}
				}
				pMB->quant = pEnc->current->quant;

				pMB->field_pred = 0;

				pMB->cbp =
					MBTransQuantInter(&pEnc->mbParam, pEnc->current, pMB, x, y,
									  dct_codes, qcoeff);
			} else {
				CodeIntraMB(pEnc, pMB);
				MBTransQuantIntra(&pEnc->mbParam, pEnc->current, pMB, x, y,
								  dct_codes, qcoeff);

				start_timer();
				MBPrediction(pEnc->current, x, y, pEnc->mbParam.mb_width, qcoeff);
				stop_prediction_timer();
			}

			if (pMB->mode == MODE_INTRA || pMB->mode == MODE_INTRA_Q) {
				pEnc->sStat.kblks++;
			} else if (pMB->cbp || pMB->mvs[0].x || pMB->mvs[0].y ||
					   pMB->mvs[1].x || pMB->mvs[1].y || pMB->mvs[2].x ||
					   pMB->mvs[2].y || pMB->mvs[3].x || pMB->mvs[3].y) {
				pEnc->sStat.mblks++;
			}  else {
				pEnc->sStat.ublks++;
			} 

			start_timer();

			/* Finished processing the MB, now check if to CODE or SKIP */

			if (pMB->cbp == 0 && pMB->mode == MODE_INTER && pMB->mvs[0].x == 0 &&
				pMB->mvs[0].y == 0) {

					MBSkip(bs);	/* without B-frames, no precautions are needed */

			}
			else {
				if (pEnc->current->global_flags & XVID_GREYSCALE) {
					pMB->cbp &= 0x3C;		/* keep only bits 5-2 */
					qcoeff[4*64+0]=0;		/* zero, because DC for INTRA MBs DC value is saved */
					qcoeff[5*64+0]=0;
				}
				MBCoding(pEnc->current, pMB, qcoeff, bs, &pEnc->sStat);
			}

			stop_coding_timer();
		}
	}

	emms();

	if (pEnc->current->global_flags & XVID_HINTEDME_GET) {
		HintedMEGet(pEnc, 0);
	}

	if (pEnc->sStat.iMvCount == 0)
		pEnc->sStat.iMvCount = 1;

	fSigma = (float) sqrt((float) pEnc->sStat.iMvSum / pEnc->sStat.iMvCount);

	iSearchRange = 1 << (3 + pEnc->mbParam.m_fcode);

	if ((fSigma > iSearchRange / 3)
		&& (pEnc->mbParam.m_fcode <= 3))	/* maximum search range 128 */
	{
		pEnc->mbParam.m_fcode++;
		iSearchRange *= 2;
	} else if ((fSigma < iSearchRange / 6)
			   && (pEnc->sStat.fMvPrevSigma >= 0)
			   && (pEnc->sStat.fMvPrevSigma < iSearchRange / 6)
			   && (pEnc->mbParam.m_fcode >= 2))	/* minimum search range 16 */
	{
		pEnc->mbParam.m_fcode--;
		iSearchRange /= 2;
	}

	pEnc->sStat.fMvPrevSigma = fSigma;

	*pBits = BitstreamPos(bs) - *pBits;

	return 0;					/* inter */

}