/* * decode.c * Copyright (C) 2000-2003 Michel Lespinasse <walken@zoy.org> * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca> * * This file is part of mpeg2dec, a free MPEG-2 video stream decoder. * See http://libmpeg2.sourceforge.net/ for updates. * * mpeg2dec 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. * * mpeg2dec 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 */#include "config.h"#include <string.h>	/* memcmp/memset, try to remove */#include <stdlib.h>#include <inttypes.h>#include "mpeg2.h"#include "attributes.h"#include "mpeg2_internal.h"

#include "getbit.h"
//#include "smartcache.h"


static int ChromaFormat[4] = {
	0, 6, 8, 12
};

static int mpeg2_accels = 0;//#define BUFFER_SIZE (1194 * 1024)const mpeg2_info_t *  mpeg2_info (mpeg2dec_t * mpeg2dec){    return &(mpeg2dec->info);}static inline int skip_chunk (mpeg2dec_t * mpeg2dec, int bytes){    uint8_t * current;    uint32_t shift;    uint8_t * limit;    uint8_t byte;    if (!bytes)	return 0;    current = mpeg2dec->buf_start;    shift = mpeg2dec->shift;    limit = current + bytes;    do {	byte = *current++;	if (shift == 0x00000100) {	    int skipped;	    mpeg2dec->shift = 0xffffff00;	    skipped = current - mpeg2dec->buf_start;	    mpeg2dec->buf_start = current;	    return skipped;	}	shift = (shift | byte) << 8;    } while (current < limit);    mpeg2dec->shift = shift;    mpeg2dec->buf_start = current;    return 0;}static inline int copy_chunk (mpeg2dec_t * mpeg2dec, int bytes){    uint8_t * current;    uint32_t shift;    uint8_t * chunk_ptr;    uint8_t * limit;    uint8_t byte;    if (!bytes)	return 0;    current = mpeg2dec->buf_start;    shift = mpeg2dec->shift;    chunk_ptr = mpeg2dec->chunk_ptr;    limit = current + bytes;    do {	byte = *current++;	if (shift == 0x00000100) {	    int copied;	    mpeg2dec->shift = 0xffffff00;	    mpeg2dec->chunk_ptr = chunk_ptr + 1;	    copied = current - mpeg2dec->buf_start;	    mpeg2dec->buf_start = current;	    return copied;	}	shift = (shift | byte) << 8;	*chunk_ptr++ = byte;    } while (current < limit);    mpeg2dec->shift = shift;    mpeg2dec->buf_start = current;    return 0;}void  mpeg2_buffer (mpeg2dec_t * mpeg2dec, uint8_t * start, uint8_t * end){    mpeg2dec->buf_start = start;    mpeg2dec->buf_end = end;}int mpeg2_getpos (mpeg2dec_t * mpeg2dec){    return mpeg2dec->buf_end - mpeg2dec->buf_start;}static inline mpeg2_state_t seek_chunk (mpeg2dec_t * mpeg2dec){    int size, skipped;    size = mpeg2dec->buf_end - mpeg2dec->buf_start;    skipped = skip_chunk (mpeg2dec, size);    if (!skipped) {	mpeg2dec->bytes_since_tag += size;	return STATE_BUFFER;    }    mpeg2dec->bytes_since_tag += skipped;    mpeg2dec->code = mpeg2dec->buf_start[-1];    return (mpeg2_state_t)-1;}mpeg2_state_t mpeg2_seek_header (mpeg2dec_t * mpeg2dec){    while (mpeg2dec->code != 0xb3 &&	   ((mpeg2dec->code != 0xb7 && mpeg2dec->code != 0xb8 &&	     mpeg2dec->code) || mpeg2dec->sequence.width == (unsigned)-1))	if (seek_chunk (mpeg2dec) == STATE_BUFFER)	    return STATE_BUFFER;    mpeg2dec->chunk_start = mpeg2dec->chunk_ptr = mpeg2dec->chunk_buffer;    mpeg2dec->user_data_len = 0;    return (mpeg2dec->code ? mpeg2_parse_header (mpeg2dec) :	    mpeg2_header_picture_start (mpeg2dec));}#define RECEIVED(code,state) (((state) << 8) + (code))mpeg2_state_t mpeg2_parse (mpeg2dec_t * mpeg2dec){    int size_buffer, size_chunk, copied;    if (mpeg2dec->action) {	mpeg2_state_t state;	state = mpeg2dec->action (mpeg2dec);	if ((int)state >= 0)	    return state;    }    while (1) {	while ((unsigned) (mpeg2dec->code - mpeg2dec->first_decode_slice) <	       mpeg2dec->nb_decode_slices) {	    size_buffer = mpeg2dec->buf_end - mpeg2dec->buf_start;	    size_chunk = (mpeg2dec->chunk_buffer + BUFFER_SIZE -			  mpeg2dec->chunk_ptr);	    if (size_buffer <= size_chunk) {		copied = copy_chunk (mpeg2dec, size_buffer);		if (!copied) {		    mpeg2dec->bytes_since_tag += size_buffer;		    mpeg2dec->chunk_ptr += size_buffer;		    return STATE_BUFFER;		}	    } else {		copied = copy_chunk (mpeg2dec, size_chunk);		if (!copied) {		    /* filled the chunk buffer without finding a start code */		    mpeg2dec->bytes_since_tag += size_chunk;		    mpeg2dec->action = seek_chunk;		    return STATE_INVALID;		}	    }	    mpeg2dec->bytes_since_tag += copied;	    mpeg2_slice (&(mpeg2dec->decoder), mpeg2dec->code,			 mpeg2dec->chunk_start);	    mpeg2dec->code = mpeg2dec->buf_start[-1];	    mpeg2dec->chunk_ptr = mpeg2dec->chunk_start;	}	if ((unsigned) (mpeg2dec->code - 1) >= 0xb0 - 1)	    break;	if (seek_chunk (mpeg2dec) == STATE_BUFFER)	    return STATE_BUFFER;    }    switch (mpeg2dec->code) {    case 0x00:	mpeg2dec->action = mpeg2_header_picture_start;	return mpeg2dec->state;    case 0xb7:	mpeg2dec->action = mpeg2_header_end;	break;    case 0xb3:    case 0xb8:	mpeg2dec->action = mpeg2_parse_header;	break;    default:	mpeg2dec->action = seek_chunk;	return STATE_INVALID;    }    return (mpeg2dec->state == STATE_SLICE) ? STATE_SLICE : STATE_INVALID;}mpeg2_state_t mpeg2_parse_header (mpeg2dec_t * mpeg2dec){    static int (* process_header[]) (mpeg2dec_t * mpeg2dec) = {	mpeg2_header_picture, mpeg2_header_extension, mpeg2_header_user_data,	mpeg2_header_sequence, NULL, NULL, NULL, NULL, mpeg2_header_gop    };    int size_buffer, size_chunk, copied;    mpeg2dec->action = mpeg2_parse_header;    mpeg2dec->info.user_data = NULL;	mpeg2dec->info.user_data_len = 0;    while (1) {	size_buffer = mpeg2dec->buf_end - mpeg2dec->buf_start;	size_chunk = (mpeg2dec->chunk_buffer + BUFFER_SIZE -		      mpeg2dec->chunk_ptr);	if (size_buffer <= size_chunk) {	    copied = copy_chunk (mpeg2dec, size_buffer);	    if (!copied) {		mpeg2dec->bytes_since_tag += size_buffer;		mpeg2dec->chunk_ptr += size_buffer;		return STATE_BUFFER;	    }	} else {	    copied = copy_chunk (mpeg2dec, size_chunk);	    if (!copied) {		/* filled the chunk buffer without finding a start code */		mpeg2dec->bytes_since_tag += size_chunk;		mpeg2dec->code = 0xb4;		mpeg2dec->action = mpeg2_seek_header;		return STATE_INVALID;	    }	}	mpeg2dec->bytes_since_tag += copied;	if (process_header[mpeg2dec->code & 0x0b] (mpeg2dec)) {	    mpeg2dec->code = mpeg2dec->buf_start[-1];	    mpeg2dec->action = mpeg2_seek_header;	    return STATE_INVALID;	}	mpeg2dec->code = mpeg2dec->buf_start[-1];	switch (RECEIVED (mpeg2dec->code, mpeg2dec->state)) {	/* state transition after a sequence header */	case RECEIVED (0x00, STATE_SEQUENCE):	    mpeg2dec->action = mpeg2_header_picture_start;	case RECEIVED (0xb8, STATE_SEQUENCE):	    mpeg2_header_sequence_finalize (mpeg2dec);	    break;	/* other legal state transitions */	case RECEIVED (0x00, STATE_GOP):	    mpeg2_header_gop_finalize (mpeg2dec);	    mpeg2dec->action = mpeg2_header_picture_start;	    break;	case RECEIVED (0x01, STATE_PICTURE):	case RECEIVED (0x01, STATE_PICTURE_2ND):	    mpeg2_header_picture_finalize (mpeg2dec, mpeg2_accels);	    mpeg2dec->action = mpeg2_header_slice_start;	    break;	/* legal headers within a given state */	case RECEIVED (0xb2, STATE_SEQUENCE):	case RECEIVED (0xb2, STATE_GOP):	case RECEIVED (0xb2, STATE_PICTURE):	case RECEIVED (0xb2, STATE_PICTURE_2ND):	case RECEIVED (0xb5, STATE_SEQUENCE):	case RECEIVED (0xb5, STATE_PICTURE):	case RECEIVED (0xb5, STATE_PICTURE_2ND):	    mpeg2dec->chunk_ptr = mpeg2dec->chunk_start;	    continue;	default:	    mpeg2dec->action = mpeg2_seek_header;	    return STATE_INVALID;	}	mpeg2dec->chunk_start = mpeg2dec->chunk_ptr = mpeg2dec->chunk_buffer;	mpeg2dec->user_data_len = 0;	return mpeg2dec->state;    }}int mpeg2_convert (mpeg2dec_t * mpeg2dec, mpeg2_convert_t convert, void * arg){    mpeg2_convert_init_t convert_init;    int error;