decoder.c

mpeg4视频解码源码.rar

/*****************************************************************************
 *
 *  XVID MPEG-4 VIDEO CODEC
 *  - Decoder Module -
 *
 *  Copyright(C) 2002      MinChen <[e-mail]>
 *               2002-2004 Peter Ross <[e-mail]>
 *
 *  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
 *
 * $Id$
 *
 ****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef BFRAMES_DEC_DEBUG
	#define BFRAMES_DEC
#endif

#include "xvid.h"
#include "portab.h"
#include "global.h"

#include "decoder.h"
#include "bitstream/bitstream.h"
#include "bitstream/mbcoding.h"

#include "quant/quant.h"
#include "quant/quant_matrix.h"
#include "dct/idct.h"
#include "dct/fdct.h"
#include "utils/mem_transfer.h"
#include "image/interpolate8x8.h"
#include "image/font.h"
#include "image/qpel.h"

#include "bitstream/mbcoding.h"
#include "prediction/mbprediction.h"
#include "utils/timer.h"
#include "utils/emms.h"
#include "motion/motion.h"
#include "motion/gmc.h"

#include "image/image.h"
#include "image/colorspace.h"
#include "image/postprocessing.h"
#include "utils/mem_align.h"

static int
decoder_resize(DECODER * dec)
{
	/* free existing */
	image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
	image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
	image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
	image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
	image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);

	image_destroy(&dec->gmc, dec->edged_width, dec->edged_height);

	if (dec->last_mbs)
		xvid_free(dec->last_mbs);
	if (dec->mbs)
		xvid_free(dec->mbs);
	if (dec->qscale)
		xvid_free(dec->qscale);

	/* realloc */
	dec->mb_width = (dec->width + 15) / 16;
	dec->mb_height = (dec->height + 15) / 16;

	dec->edged_width = 16 * dec->mb_width + 2 * EDGE_SIZE;
	dec->edged_height = 16 * dec->mb_height + 2 * EDGE_SIZE;

	if (image_create(&dec->cur, dec->edged_width, dec->edged_height)) {
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	if (image_create(&dec->refn[0], dec->edged_width, dec->edged_height)) {
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	/* Support B-frame to reference last 2 frame */
	if (image_create(&dec->refn[1], dec->edged_width, dec->edged_height)) {
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}
	if (image_create(&dec->tmp, dec->edged_width, dec->edged_height)) {
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	if (image_create(&dec->qtmp, dec->edged_width, dec->edged_height)) {
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	if (image_create(&dec->gmc, dec->edged_width, dec->edged_height)) {
		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	dec->mbs =
		xvid_malloc(sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height,
					CACHE_LINE);
	if (dec->mbs == NULL) {
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}
	memset(dec->mbs, 0, sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height);

	/* For skip MB flag */
	dec->last_mbs =
		xvid_malloc(sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height,
					CACHE_LINE);
	if (dec->last_mbs == NULL) {
		xvid_free(dec->mbs);
		image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
		image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
		image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
		image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	memset(dec->last_mbs, 0, sizeof(MACROBLOCK) * dec->mb_width * dec->mb_height);

	/* nothing happens if that fails */
	dec->qscale =
		xvid_malloc(sizeof(int) * dec->mb_width * dec->mb_height, CACHE_LINE);
	
	if (dec->qscale)
		memset(dec->qscale, 0, sizeof(int) * dec->mb_width * dec->mb_height);

	return 0;
}


int
decoder_create(xvid_dec_create_t * create)
{
	DECODER *dec;

	if (XVID_VERSION_MAJOR(create->version) != 1)	/* v1.x.x */
		return XVID_ERR_VERSION;

	dec = xvid_malloc(sizeof(DECODER), CACHE_LINE);
	if (dec == NULL) {
		return XVID_ERR_MEMORY;
	}

	memset(dec, 0, sizeof(DECODER));

	dec->mpeg_quant_matrices = xvid_malloc(sizeof(uint16_t) * 64 * 8, CACHE_LINE);
	if (dec->mpeg_quant_matrices == NULL) {
		xvid_free(dec);
		return XVID_ERR_MEMORY;
	}

	create->handle = dec;

	dec->width = create->width;
	dec->height = create->height;

	image_null(&dec->cur);
	image_null(&dec->refn[0]);
	image_null(&dec->refn[1]);
	image_null(&dec->tmp);
	image_null(&dec->qtmp);

	/* image based GMC */
	image_null(&dec->gmc);

	dec->mbs = NULL;
	dec->last_mbs = NULL;
	dec->qscale = NULL;

	init_timer();
	init_postproc(&dec->postproc);
	init_mpeg_matrix(dec->mpeg_quant_matrices);

	/* For B-frame support (used to save reference frame's time */
	dec->frames = 0;
	dec->time = dec->time_base = dec->last_time_base = 0;
	dec->low_delay = 0;
	dec->packed_mode = 0;
	dec->time_inc_resolution = 1; /* until VOL header says otherwise */

	dec->fixed_dimensions = (dec->width > 0 && dec->height > 0);

	if (dec->fixed_dimensions)
		return decoder_resize(dec);
	else
		return 0;
}


int
decoder_destroy(DECODER * dec)
{
	xvid_free(dec->last_mbs);
	xvid_free(dec->mbs);
	xvid_free(dec->qscale);

	/* image based GMC */
	image_destroy(&dec->gmc, dec->edged_width, dec->edged_height);

	image_destroy(&dec->refn[0], dec->edged_width, dec->edged_height);
	image_destroy(&dec->refn[1], dec->edged_width, dec->edged_height);
	image_destroy(&dec->tmp, dec->edged_width, dec->edged_height);
	image_destroy(&dec->qtmp, dec->edged_width, dec->edged_height);
	image_destroy(&dec->cur, dec->edged_width, dec->edged_height);
	xvid_free(dec->mpeg_quant_matrices);
	xvid_free(dec);

	write_timer();
	return 0;
}

static const int32_t dquant_table[4] = {
	-1, -2, 1, 2
};

/* decode an intra macroblock */
static void
decoder_mbintra(DECODER * dec,
				MACROBLOCK * pMB,
				const uint32_t x_pos,
				const uint32_t y_pos,
				const uint32_t acpred_flag,
				const uint32_t cbp,
				Bitstream * bs,
				const uint32_t quant,
				const uint32_t intra_dc_threshold,
				const unsigned int bound)
{

	DECLARE_ALIGNED_MATRIX(block, 6, 64, int16_t, CACHE_LINE);
	DECLARE_ALIGNED_MATRIX(data, 6, 64, int16_t, CACHE_LINE);

	uint32_t stride = dec->edged_width;
	uint32_t stride2 = stride / 2;
	uint32_t next_block = stride * 8;
	uint32_t i;
	uint32_t iQuant = pMB->quant;
	uint8_t *pY_Cur, *pU_Cur, *pV_Cur;

	pY_Cur = dec->cur.y + (y_pos << 4) * stride + (x_pos << 4);
	pU_Cur = dec->cur.u + (y_pos << 3) * stride2 + (x_pos << 3);
	pV_Cur = dec->cur.v + (y_pos << 3) * stride2 + (x_pos << 3);

	memset(block, 0, 6 * 64 * sizeof(int16_t));	/* clear */

	for (i = 0; i < 6; i++) {
		uint32_t iDcScaler = get_dc_scaler(iQuant, i < 4);
		int16_t predictors[8];
		int start_coeff;

		start_timer();
		predict_acdc(dec->mbs, x_pos, y_pos, dec->mb_width, i, &block[i * 64],
					 iQuant, iDcScaler, predictors, bound);
		if (!acpred_flag) {
			pMB->acpred_directions[i] = 0;
		}
		stop_prediction_timer();

		if (quant < intra_dc_threshold) {
			int dc_size;
			int dc_dif;

			dc_size = i < 4 ? get_dc_size_lum(bs) : get_dc_size_chrom(bs);
			dc_dif = dc_size ? get_dc_dif(bs, dc_size) : 0;

			if (dc_size > 8) {
				BitstreamSkip(bs, 1);	/* marker */
			}

			block[i * 64 + 0] = dc_dif;
			start_coeff = 1;

			DPRINTF(XVID_DEBUG_COEFF,"block[0] %i\n", dc_dif);
		} else {
			start_coeff = 0;
		}

		start_timer();
		if (cbp & (1 << (5 - i)))	/* coded */
		{
			int direction = dec->alternate_vertical_scan ?
				2 : pMB->acpred_directions[i];

			get_intra_block(bs, &block[i * 64], direction, start_coeff);
		}
		stop_coding_timer();

		start_timer();
		add_acdc(pMB, i, &block[i * 64], iDcScaler, predictors, dec->bs_version);
		stop_prediction_timer();

		start_timer();
		if (dec->quant_type == 0) {
			dequant_h263_intra(&data[i * 64], &block[i * 64], iQuant, iDcScaler, dec->mpeg_quant_matrices);
		} else {
			dequant_mpeg_intra(&data[i * 64], &block[i * 64], iQuant, iDcScaler, dec->mpeg_quant_matrices);
		}
		stop_iquant_timer();

		start_timer();
		idct(&data[i * 64]);
		stop_idct_timer();

	}

	if (dec->interlacing && pMB->field_dct) {
		next_block = stride;
		stride *= 2;
	}

	start_timer();
	transfer_16to8copy(pY_Cur, &data[0 * 64], stride);
	transfer_16to8copy(pY_Cur + 8, &data[1 * 64], stride);
	transfer_16to8copy(pY_Cur + next_block, &data[2 * 64], stride);
	transfer_16to8copy(pY_Cur + 8 + next_block, &data[3 * 64], stride);
	transfer_16to8copy(pU_Cur, &data[4 * 64], stride2);
	transfer_16to8copy(pV_Cur, &data[5 * 64], stride2);
	stop_transfer_timer();
}

static void
decoder_mb_decode(DECODER * dec,
				const uint32_t cbp,
				Bitstream * bs,
				uint8_t * pY_Cur,
				uint8_t * pU_Cur,
				uint8_t * pV_Cur,
				const MACROBLOCK * pMB)
{
	DECLARE_ALIGNED_MATRIX(data, 1, 64, int16_t, CACHE_LINE);

	int stride = dec->edged_width;
	int next_block = stride * 8;
	int i;
	const uint32_t iQuant = pMB->quant;
	const int direction = dec->alternate_vertical_scan ? 2 : 0;
	typedef void (*get_inter_block_function_t)(
			Bitstream * bs,
			int16_t * block,
			int direction,
			const int quant,
			const uint16_t *matrix);
	typedef void (*add_residual_function_t)(
			uint8_t *predicted_block,
			const int16_t *residual,
			int stride);

	const get_inter_block_function_t get_inter_block = (dec->quant_type == 0)
		? (get_inter_block_function_t)get_inter_block_h263
		: (get_inter_block_function_t)get_inter_block_mpeg;

	uint8_t *dst[6];
	int strides[6];
	

	if (dec->interlacing && pMB->field_dct) {
		next_block = stride;
		stride *= 2;
	}

	dst[0] = pY_Cur;
	dst[2] = pY_Cur + next_block;
	dst[1] = dst[0] + 8;
	dst[3] = dst[2] + 8;
	dst[4] = pU_Cur;
	dst[5] = pV_Cur;
	strides[0] = strides[1] = strides[2] = strides[3] = stride;
	strides[4] = stride/2;
	strides[5] = stride/2;
	
	for (i = 0; i < 6; i++) {
		/* Process only coded blocks */
		if (cbp & (1 << (5 - i))) {

			/* Clear the block */
			memset(&data[0], 0, 64*sizeof(int16_t));

			/* Decode coeffs and dequantize on the fly */
			start_timer();
			get_inter_block(bs, &data[0], direction, iQuant, get_inter_matrix(dec->mpeg_quant_matrices));
			stop_coding_timer();

			/* iDCT */
			start_timer();
			idct(&data[0]);
			stop_idct_timer();

			/* Add this residual to the predicted block */
			start_timer();
			transfer_16to8add(dst[i], &data[0], strides[i]);
			stop_transfer_timer();
		}
	}
}

static void __inline
validate_vector(VECTOR * mv, unsigned int x_pos, unsigned int y_pos, const DECODER * dec)
{
	/* clip a vector to valid range 
	   prevents crashes if bitstream is broken 
	*/
	int shift = 5 + dec->quarterpel;
	int xborder_high = (int)(dec->mb_width - x_pos) << shift;
	int xborder_low = (-(int)x_pos-1) << shift;
	int yborder_high = (int)(dec->mb_height - y_pos) << shift;
	int yborder_low = (-(int)y_pos-1) << shift;

#define CHECK_MV(mv) \
	do { \
	if ((mv).x > xborder_high) { \
		DPRINTF(XVID_DEBUG_MV, "mv.x > max -- %d > %d, MB %d, %d", (mv).x, xborder_high, x_pos, y_pos); \
		(mv).x = xborder_high; \
	} else if ((mv).x < xborder_low) { \
		DPRINTF(XVID_DEBUG_MV, "mv.x < min -- %d < %d, MB %d, %d", (mv).x, xborder_low, x_pos, y_pos); \
		(mv).x = xborder_low; \
	} \
	if ((mv).y > yborder_high) { \
		DPRINTF(XVID_DEBUG_MV, "mv.y > max -- %d > %d, MB %d, %d", (mv).y, yborder_high, x_pos, y_pos); \
		(mv).y = yborder_high; \
	} else if ((mv).y < yborder_low) { \
		DPRINTF(XVID_DEBUG_MV, "mv.y < min -- %d < %d, MB %d, %d", (mv).y, yborder_low, x_pos, y_pos); \
		(mv).y = yborder_low; \
	} \
	} while (0)

	CHECK_MV(mv[0]);
	CHECK_MV(mv[1]);
	CHECK_MV(mv[2]);
	CHECK_MV(mv[3]);
}

/* decode an inter macroblock */
static void
decoder_mbinter(DECODER * dec,
				const MACROBLOCK * pMB,
				const uint32_t x_pos,
				const uint32_t y_pos,
				const uint32_t cbp,
				Bitstream * bs,
				const uint32_t rounding,
				const int ref)
{
	uint32_t stride = dec->edged_width;
	uint32_t stride2 = stride / 2;
	uint32_t i;

	uint8_t *pY_Cur, *pU_Cur, *pV_Cur;

	int uv_dx, uv_dy;
	VECTOR mv[4];	/* local copy of mvs */

	pY_Cur = dec->cur.y + (y_pos << 4) * stride + (x_pos << 4);
	pU_Cur = dec->cur.u + (y_pos << 3) * stride2 + (x_pos << 3);
	pV_Cur = dec->cur.v + (y_pos << 3) * stride2 + (x_pos << 3);
	for (i = 0; i < 4; i++)
		mv[i] = pMB->mvs[i];

	validate_vector(mv, x_pos, y_pos, dec);

	start_timer();

	if (pMB->mode != MODE_INTER4V) { /* INTER, INTER_Q, NOT_CODED, FORWARD, BACKWARD */

		uv_dx = mv[0].x;
		uv_dy = mv[0].y;
		if (dec->quarterpel) {
			uv_dx /= 2;
			uv_dy /= 2;
		}
		uv_dx = (uv_dx >> 1) + roundtab_79[uv_dx & 0x3];