demux_real.c

来自「君正早期ucos系统(只有早期的才不没有打包成库),MPLAYER,文件系统,图」· C语言 代码 · 共 1,820 行 · 第 1/5 页

/*
    Real parser & demuxer
    
    (C) Alex Beregszaszi
    (C) 2005, 2006 Roberto Togni
    
    Based on FFmpeg's libav/rm.c.

Audio codecs: (supported by RealPlayer8 for Linux)
    DNET - RealAudio 3.0, really it's AC3 in swapped-byteorder
    SIPR - SiproLab's audio codec, ACELP decoder working with MPlayer,
	   needs fine-tuning too :)
    ATRC - RealAudio 8 (ATRAC3) - www.minidisc.org/atrac3_article.pdf,
           ACM decoder uploaded, needs some fine-tuning to work
	   -> RealAudio 8
    COOK/COKR - Real Cooker -> RealAudio G2

Video codecs: (supported by RealPlayer8 for Linux)
    RV10 - H.263 based, working with libavcodec's decoder
    RV20-RV40 - using RealPlayer's codec plugins
*/

#include <mplaylib.h>
#include <mplaylib.h>
#include <mplaylib.h>
#include <inttypes.h>

#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"

#include "stream/stream.h"
#include "demuxer.h"
#include "stheader.h"

#ifdef USE_LIBAVCODEC_SO
#include <ffmpeg/avcodec.h>
#elif defined(USE_LIBAVCODEC)
#include "libavcodec/avcodec.h"
#else
#define FF_INPUT_BUFFER_PADDING_SIZE 8
#endif
#define SEEK_ABSOLUTE (1 << 0)
#define SEEK_FACTOR   (1 << 1)
//#define mp_dbg(mod,lev, args... ) mp_msg_c((mod<<8)|lev, ## args )

#define MKTAG(a, b, c, d) (a | (b << 8) | (c << 16) | (d << 24))
#undef memcpy
#define memcpy uc_memcpy
#define MAX_STREAMS 32
//#undef F(x,s...)
//#define F(x,s...)

static unsigned char sipr_swaps[38][2]={
    {0,63},{1,22},{2,44},{3,90},{5,81},{7,31},{8,86},{9,58},{10,36},{12,68},
    {13,39},{14,73},{15,53},{16,69},{17,57},{19,88},{20,34},{21,71},{24,46},
    {25,94},{26,54},{28,75},{29,50},{32,70},{33,92},{35,74},{38,85},{40,56},
    {42,87},{43,65},{45,59},{48,79},{49,93},{51,89},{55,95},{61,76},{67,83},
    {77,80} };

typedef struct {
    unsigned int	timestamp;
    int		offset;
//    int		packetno;
//    int		len; /* only filled by our index generator */
//    int		flags; /* only filled by our index generator */
} real_index_table_t;

typedef struct {
    /* for seeking */
    int		index_chunk_offset;
    real_index_table_t *index_table[MAX_STREAMS];
	
//    int		*index_table[MAX_STREAMS];
    int		index_table_size[MAX_STREAMS];
    int		index_malloc_size[MAX_STREAMS];
    int		data_chunk_offset;
    int		num_of_packets;
    int		current_packet;
	
// need for seek
    int		audio_need_keyframe;
    int		video_after_seek;

    int		current_apacket;
    int		current_vpacket;
    
    // timestamp correction:
    int64_t		kf_base;// timestamp of the prev. video keyframe
    unsigned int	kf_pts;	// timestamp of next video keyframe
    unsigned int	a_pts;	// previous audio timestamp
    double	v_pts;  // previous video timestamp
    unsigned long	duration;
    
    /* stream id table */
//    int		last_a_stream;
//    int 	a_streams[MAX_STREAMS];
//    int		last_v_stream;
//    int 	v_streams[MAX_STREAMS];

    /**
     * Used to demux multirate files
     */
    int is_multirate; ///< != 0 for multirate files
    int str_data_offset[MAX_STREAMS]; ///< Data chunk offset for every audio/video stream
    int audio_curpos; ///< Current file position for audio demuxing
    int video_curpos; ///< Current file position for video demuxing
    int a_num_of_packets; ///< Number of audio packets
    int v_num_of_packets; ///< Number of video packets
    int a_idx_ptr; ///< Audio index position pointer
    int v_idx_ptr; ///< Video index position pointer
    int a_bitrate; ///< Audio bitrate
    int v_bitrate; ///< Video bitrate
    int stream_switch; ///< Flag used to switch audio/video demuxing

   /**
    * Used to reorder audio data
    */
    unsigned int intl_id[MAX_STREAMS]; ///< interleaver id, per stream
    int sub_packet_size[MAX_STREAMS]; ///< sub packet size, per stream
    int sub_packet_h[MAX_STREAMS]; ///< number of coded frames per block
    int coded_framesize[MAX_STREAMS]; ///< coded frame size, per stream
    int audiopk_size[MAX_STREAMS]; ///< audio packet size
    unsigned char *audio_buf; ///< place to store reordered audio data
    double *audio_timestamp; ///< timestamp for each audio packet
    int sub_packet_cnt; ///< number of subpacket already received
    int audio_filepos; ///< file position of first audio packet in block
} real_priv_t;

//! use at most 200 MB of memory for index, corresponds to around 25 million entries
#define MAX_INDEX_ENTRIES (200*1024*1024 / sizeof(real_index_table_t))

/* originally from FFmpeg */
static void get_str(int isbyte, demuxer_t *demuxer, char *buf, int buf_size)
{
    int len;
    
    if (isbyte)
	len = stream_read_char(demuxer->stream);
    else
	len = stream_read_word(demuxer->stream);

    stream_read(demuxer->stream, buf, (len > buf_size) ? buf_size : len);
    if (len > buf_size)
	stream_skip(demuxer->stream, len-buf_size);

    mp_msg(MSGT_DEMUX, MSGL_V, "read_str: %d bytes read\n", len);
}

static void dump_index(demuxer_t *demuxer, int stream_id)
{
    real_priv_t *priv = demuxer->priv;
    real_index_table_t *index;
    int i, entries;

    if ( mp_msg_test(MSGT_DEMUX,MSGL_V) )
	return;
    
    if ((unsigned)stream_id >= MAX_STREAMS)
	return;

    index = priv->index_table[stream_id];
    entries = priv->index_table_size[stream_id];
    
    mp_msg(MSGT_DEMUX, MSGL_V, "Index table for stream %d\n", stream_id);
    for (i = 0; i < entries; i++)
    {
#if 1
	mp_msg(MSGT_DEMUX, MSGL_V,"i: %d, pos: %d, timestamp: %u\n", i, index[i].offset, index[i].timestamp);
#else
	mp_msg(MSGT_DEMUX, MSGL_V,"packetno: %x pos: %x len: %x timestamp: %x flags: %x\n",
	    index[i].packetno, index[i].offset, index[i].len, index[i].timestamp,
	    index[i].flags);
#endif
    }
}

static int parse_index_chunk(demuxer_t *demuxer)
{
    real_priv_t *priv = demuxer->priv;
    int origpos = stream_tell(demuxer->stream);
    int next_header_pos = priv->index_chunk_offset;
    int i, entries, stream_id;

read_index:
		stream_seek(demuxer->stream, next_header_pos);

    i = stream_read_dword_le(demuxer->stream);
    if ((i == -256) || (i != MKTAG('I', 'N', 'D', 'X')))
    {
	mp_msg(MSGT_DEMUX, MSGL_WARN,"Something went wrong, no index chunk found on given address (%d)\n",
	    next_header_pos);
	index_mode = -1;
        if (i == -256)
	    stream_reset(demuxer->stream);
	    
    	stream_seek(demuxer->stream, origpos);
	return 0;
	//goto end;
    }

    mp_msg(MSGT_DEMUX, MSGL_V,"Reading index table from index chunk (%d)\n",
	next_header_pos);

    i = stream_read_dword(demuxer->stream);
    mp_msg(MSGT_DEMUX, MSGL_V,"size: %d bytes\n", i);

    i = stream_read_word(demuxer->stream);
    if (i != 0)
	mp_msg(MSGT_DEMUX, MSGL_WARN,"Hmm, index table with unknown version (%d), please report it to MPlayer developers!\n", i);

    entries = stream_read_dword(demuxer->stream);
    mp_msg(MSGT_DEMUX, MSGL_V,"entries: %d\n", entries);
    
    stream_id = stream_read_word(demuxer->stream);
    mp_msg(MSGT_DEMUX, MSGL_V,"stream_id: %d\n", stream_id);
    
    next_header_pos = stream_read_dword(demuxer->stream);
    mp_msg(MSGT_DEMUX, MSGL_V,"next_header_pos: %d\n", next_header_pos);
    if (entries <= 0 || entries > MAX_INDEX_ENTRIES)
    {
	if (next_header_pos)
	    goto read_index;
	i = entries;
	goto end;
    }

    priv->index_table_size[stream_id] = entries;
    priv->index_table[stream_id] = calloc(priv->index_table_size[stream_id], sizeof(real_index_table_t));
    
    for (i = 0; i < entries; i++)
    {
	stream_skip(demuxer->stream, 2); /* version */
	priv->index_table[stream_id][i].timestamp = stream_read_dword(demuxer->stream);
	priv->index_table[stream_id][i].offset = stream_read_dword(demuxer->stream);
	//F("offset = %d %d",i,priv->index_table[stream_id][i].offset);
	stream_skip(demuxer->stream, 4); /* packetno */
//priv->index_table[stream_id][i].packetno = stream_read_dword(demuxer->stream);
	//unsigned int packetno = stream_read_dword(demuxer->stream);
	
	//printf("Index table: Stream#%d: entry: %d: pos: %d :timestamp: %d packetno: %d\n",
	//    stream_id, i, priv->index_table[stream_id][i].offset,priv->index_table[stream_id][i].timestamp,packetno);
    }
    
    dump_index(demuxer, stream_id);

    if (next_header_pos > 0)
	goto read_index;

end:
    if (i == -256)
			stream_reset(demuxer->stream);
		stream_seek(demuxer->stream, origpos);
    if (i == -256)
	return 0;
    else
	return 1;
}

#if 1

static void add_index_item(demuxer_t *demuxer, int stream_id, unsigned int timestamp, int offset)
{
  if ((unsigned)stream_id < MAX_STREAMS)
  {
    real_priv_t *priv = demuxer->priv;
    real_index_table_t *index;
    if (priv->index_table_size[stream_id] >= MAX_INDEX_ENTRIES) {
      mp_msg(MSGT_DEMUXER, MSGL_WARN, "Index too large during building\n");
      return;
    }
    if (priv->index_table_size[stream_id] >= priv->index_malloc_size[stream_id])
    {
      if (priv->index_malloc_size[stream_id] == 0)
	priv->index_malloc_size[stream_id] = 2048;
      else
	priv->index_malloc_size[stream_id] += priv->index_malloc_size[stream_id] / 2;
      // in case we have a really large chunk...
      if (priv->index_table_size[stream_id] >=
            priv->index_malloc_size[stream_id])
        priv->index_malloc_size[stream_id] =
          priv->index_table_size[stream_id] + 1;
      priv->index_table[stream_id] = realloc(priv->index_table[stream_id], priv->index_malloc_size[stream_id]*sizeof(priv->index_table[0][0]));
    }
    if (priv->index_table_size[stream_id] > 0)
    {
      index = &priv->index_table[stream_id][priv->index_table_size[stream_id] - 1];
      if (index->timestamp >= timestamp || index->offset >= offset)
	return;
    }
    index = &priv->index_table[stream_id][priv->index_table_size[stream_id]++];
    index->timestamp = timestamp;
    index->offset = offset;
  }
}

static void add_index_segment(demuxer_t *demuxer, int seek_stream_id, int64_t seek_timestamp)
{
  int tag, len, stream_id, flags;
  unsigned int timestamp;
  if (seek_timestamp != -1 && (unsigned)seek_stream_id >= MAX_STREAMS)
    return;
  while (1)
  {
    demuxer->filepos = stream_tell(demuxer->stream);
    
    tag = stream_read_dword(demuxer->stream);
    if (tag == MKTAG('A', 'T', 'A', 'D'))
    {
      stream_skip(demuxer->stream, 14);
      continue; /* skip to next loop */
    }
    len = tag & 0xffff;
    if (tag == -256 || len < 12)
      break;
    
    stream_id = stream_read_word(demuxer->stream);
    timestamp = stream_read_dword(demuxer->stream);
    
    stream_skip(demuxer->stream, 1); /* reserved */
    flags = stream_read_char(demuxer->stream);
    
    if (flags == -256)
      break;
    
    if (flags & 2)
    {
      add_index_item(demuxer, stream_id, timestamp, demuxer->filepos);
      if (stream_id == seek_stream_id && timestamp >= seek_timestamp)
      {
      	stream_seek(demuxer->stream, demuxer->filepos);
	return;
      }
    }
    // printf("Index: stream=%d packet=%d timestamp=%u len=%d flags=0x%x datapos=0x%x\n", stream_id, entries, timestamp, len, flags, index->offset);
    /* skip data */
    stream_skip(demuxer->stream, len-12);
  }
}

static int generate_index(demuxer_t *demuxer)
{
  real_priv_t *priv = demuxer->priv;
  int origpos = stream_tell(demuxer->stream);
  int data_pos = priv->data_chunk_offset-10;
  int i;
  int tag;
  stream_seek(demuxer->stream, data_pos);
  tag = stream_read_dword(demuxer->stream);
  if (tag != MKTAG('A', 'T', 'A', 'D'))
  {
    mp_msg(MSGT_DEMUX, MSGL_WARN,"Something went wrong, no data chunk found on given address (%d)\n", data_pos);
  }
  else
  {
    stream_skip(demuxer->stream, 14);
    add_index_segment(demuxer, -1, -1);
  }
  for (i = 0; i < MAX_STREAMS; i++)
  {
    if (priv->index_table_size[i] > 0)
    {
      dump_index(demuxer, i);
    }