demux_ogg.c

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	      ogg_d->pos -= pa;
	      continue;
	    }
	    /// We need more data
	    buf = ogg_sync_buffer(sync,BLOCK_SIZE);	    
	    len = stream_read(s,buf,BLOCK_SIZE);
	    if(len == 0 && s->eof) {
	      mp_msg(MSGT_DEMUX,MSGL_DBG2,"Ogg : Stream EOF !!!!\n");
	      return 0;
	    }
	    ogg_sync_wrote(sync,len);
	  } /// Page loop
	  ogg_d->last_size = pa;
	  /// Find the page's logical stream
	  if( (id = demux_ogg_get_page_stream(ogg_d,&os)) < 0) {
	    mp_msg(MSGT_DEMUX,MSGL_ERR,"Ogg demuxer error : we met an unknown stream\n");
	    return 0;
	  }
	  /// Take the page
	  if(ogg_stream_pagein(os,page) == 0)
	    break;
	  /// Page was invalid => retry
	  mp_msg(MSGT_DEMUX,MSGL_WARN,"Ogg demuxer : got invalid page !!!!!\n");
	  ogg_d->pos += ogg_d->last_size;
	}
      } else /// Packet was corrupted
	mp_msg(MSGT_DEMUX,MSGL_WARN,"Ogg : bad packet in stream %d\n",id);
    } /// Packet loop
    
    /// Is the actual logical stream in use ?
    if(id == d->audio->id)
      ds = d->audio;
    else if(id == d->video->id)
      ds = d->video;
    else if (ogg_d->subs[id].text)
      ds = d->sub;

    if(ds) {
      if(!demux_ogg_add_packet(ds,&ogg_d->subs[id],id,&pack))
	continue; /// Unuseful packet, get another
      d->filepos = ogg_d->pos;
      return 1;
    }

  } /// while(1)

}

/// For avi with Ogg audio stream we have to create an ogg demuxer for this
// stream, then we join the avi and ogg demuxer with a demuxers demuxer
demuxer_t* init_avi_with_ogg(demuxer_t* demuxer) {
  demuxer_t  *od;
  ogg_demuxer_t *ogg_d;
  stream_t* s;
  uint32_t hdrsizes[3];
  demux_packet_t *dp;
  sh_audio_t *sh_audio = demuxer->audio->sh;
  int np;
  unsigned char *p = NULL,*buf;
  int plen;

  /// Check that the cbSize is enouth big for the following reads
  if(sh_audio->wf->cbSize < 22+3*sizeof(uint32_t)) {
    mp_msg(MSGT_DEMUX,MSGL_ERR,"AVI Ogg : Initial audio header is too small !!!!!\n");
    goto fallback;
  }
  /// Get the size of the 3 header packet
  memcpy(hdrsizes, ((unsigned char*)sh_audio->wf)+22+sizeof(WAVEFORMATEX), 3*sizeof(uint32_t));
//  printf("\n!!!!!! hdr sizes: %d %d %d   \n",hdrsizes[0],hdrsizes[1],hdrsizes[2]);

  /// Check the size
  if(sh_audio->wf->cbSize < 22+3*sizeof(uint32_t)+hdrsizes[0]+hdrsizes[1] + hdrsizes[2]) {
    mp_msg(MSGT_DEMUX,MSGL_ERR,"AVI Ogg : Audio header is too small !!!!!\n");
    goto fallback;
  }

  // Build the ogg demuxer private datas
  ogg_d = (ogg_demuxer_t*)calloc(1,sizeof(ogg_demuxer_t));
  ogg_d->num_sub = 1;
  ogg_d->subs = (ogg_stream_t*)malloc(sizeof(ogg_stream_t));
  ogg_d->subs[0].vorbis = 1;

   // Init the ogg physical stream
  ogg_sync_init(&ogg_d->sync);

  // Get the first page of the stream : we assume there only 1 logical stream
  while((np = ogg_sync_pageout(&ogg_d->sync,&ogg_d->page)) <= 0 ) {
    if(np < 0) {
      mp_msg(MSGT_DEMUX,MSGL_ERR,"AVI Ogg error : Can't init using first stream packets\n");
      free(ogg_d);
      goto fallback;
    }
    // Add some data
    plen = ds_get_packet(demuxer->audio,&p);    
    buf = ogg_sync_buffer(&ogg_d->sync,plen);
    memcpy(buf,p,plen);
    ogg_sync_wrote(&ogg_d->sync,plen);
  }
  // Init the logical stream
  mp_msg(MSGT_DEMUX,MSGL_DBG2,"AVI Ogg found page with serial %d\n",ogg_page_serialno(&ogg_d->page));
  ogg_stream_init(&ogg_d->subs[0].stream,ogg_page_serialno(&ogg_d->page));
  // Write the page
  ogg_stream_pagein(&ogg_d->subs[0].stream,&ogg_d->page);

  // Create the ds_stream and the ogg demuxer
  s = new_ds_stream(demuxer->audio);
  od = new_demuxer(s,DEMUXER_TYPE_OGG,0,-2,-2);

  /// Add the header packets in the ogg demuxer audio stream
  // Initial header
  dp = new_demux_packet(hdrsizes[0]);
  memcpy(dp->buffer,((unsigned char*)sh_audio->wf)+22+sizeof(WAVEFORMATEX)+3*sizeof(uint32_t),hdrsizes[0]);
  ds_add_packet(od->audio,dp);
  /// Comments
  dp = new_demux_packet(hdrsizes[1]);
  memcpy(dp->buffer,((unsigned char*)sh_audio->wf)+22+sizeof(WAVEFORMATEX)+3*sizeof(uint32_t)+hdrsizes[0],hdrsizes[1]);
  ds_add_packet(od->audio,dp);
  /// Code book
  dp = new_demux_packet(hdrsizes[2]);
  memcpy(dp->buffer,((unsigned char*)sh_audio->wf)+22+sizeof(WAVEFORMATEX)+3*sizeof(uint32_t)+hdrsizes[0]+hdrsizes[1],hdrsizes[2]);
  ds_add_packet(od->audio,dp);

  // Finish setting up the ogg demuxer
  od->priv = ogg_d;
  sh_audio = new_sh_audio(od,0);
  od->audio->id = 0;
  od->video->id = -2;
  od->audio->sh = sh_audio;
  sh_audio->ds = od->audio;
  sh_audio->format = FOURCC_VORBIS;

  /// Return the joined demuxers
  return new_demuxers_demuxer(demuxer,od,demuxer);

 fallback:
  demuxer->audio->id = -2;
  return demuxer;

}

extern void resync_audio_stream(sh_audio_t *sh_audio);

void demux_ogg_seek(demuxer_t *demuxer,float rel_seek_secs,int flags) {
  ogg_demuxer_t* ogg_d = demuxer->priv;
  ogg_sync_state* sync = &ogg_d->sync;
  ogg_page* page= &ogg_d->page;
  ogg_stream_state* oss;
  ogg_stream_t* os;
  demux_stream_t* ds;
  sh_audio_t* sh_audio = demuxer->audio->sh;
  ogg_packet op;
  float rate;
  int i,sp,first,precision=1,do_seek=1;
  vorbis_info* vi = NULL;
  int64_t gp = 0, old_gp;
  void *context = NULL;
  off_t pos, old_pos;
  int np;
  int is_gp_valid;
  float pts;
  int is_keyframe;
  int samplesize=1;

  if(demuxer->video->id >= 0) {
    ds = demuxer->video;
    /* demux_ogg_read_packet needs decoder context for Theora streams */
    if (((sh_video_t*)demuxer->video->sh)->format == FOURCC_THEORA)
      context = ((sh_video_t*)demuxer->video->sh)->context;
    rate = ogg_d->subs[ds->id].samplerate;
  } else {
    ds = demuxer->audio;
    /* demux_ogg_read_packet needs decoder context for Vorbis streams */
    if(((sh_audio_t*)demuxer->audio->sh)->format == FOURCC_VORBIS)
      context = ((sh_audio_t*)demuxer->audio->sh)->context;
    vi = &((ov_struct_t*)((sh_audio_t*)ds->sh)->context)->vi;
    rate = (float)vi->rate;
    samplesize = ((sh_audio_t*)ds->sh)->samplesize;
  }

  os = &ogg_d->subs[ds->id];
  oss = &os->stream;

  old_gp = os->lastpos;
  old_pos = ogg_d->pos;

  //calculate the granulepos to seek to
    gp = flags & 1 ? 0 : os->lastpos;
  if(flags & 2) {
    if (ogg_d->final_granulepos > 0)
      gp += ogg_d->final_granulepos * rel_seek_secs;
      else
      gp += rel_seek_secs * (demuxer->movi_end - demuxer->movi_start) * os->lastpos / ogg_d->pos;
  } else
      gp += rel_seek_secs * rate;
  if (gp < 0) gp = 0;

  //calculate the filepos to seek to
  if(ogg_d->syncpoints) {
    for(sp = 0; sp < ogg_d->num_syncpoint ; sp++) {
      if(ogg_d->syncpoints[sp].granulepos >= gp) break;
    }

    if(sp >= ogg_d->num_syncpoint) return;
    if (sp > 0 && ogg_d->syncpoints[sp].granulepos - gp > gp - ogg_d->syncpoints[sp-1].granulepos)
      sp--;
    if (ogg_d->syncpoints[sp].granulepos == os->lastpos) {
      if (sp > 0 && gp < os->lastpos) sp--;
      if (sp < ogg_d->num_syncpoint-1 && gp > os->lastpos) sp++;
    }
    pos = ogg_d->syncpoints[sp].page_pos;
    precision = 0;
  } else {
    pos = flags & 1 ? 0 : ogg_d->pos;
    if(flags & 2)
      pos += (demuxer->movi_end - demuxer->movi_start) * rel_seek_secs;
    else {
      if (ogg_d->final_granulepos > 0) {
        pos += rel_seek_secs * (demuxer->movi_end - demuxer->movi_start) / (ogg_d->final_granulepos / rate);
      } else if (os->lastpos > 0) {
      pos += rel_seek_secs * ogg_d->pos / (os->lastpos / rate);
    }
  }
    if (pos < 0) pos = 0;
    if (pos > (demuxer->movi_end - demuxer->movi_start)) return;
  } // if(ogg_d->syncpoints)

  while(1) {
    if (do_seek) {
  stream_seek(demuxer->stream,pos+demuxer->movi_start);
  ogg_sync_reset(sync);
  for(i = 0 ; i < ogg_d->num_sub ; i++) {
    ogg_stream_reset(&ogg_d->subs[i].stream);
    ogg_d->subs[i].lastpos = ogg_d->subs[i].lastsize = 0;
  }
  ogg_d->pos = pos;
  ogg_d->last_size = 0;
      /* we just guess that we reached correct granulepos, in case a
         subsequent search occurs before we read a valid granulepos */
      os->lastpos = gp;
      first = !(ogg_d->syncpoints);
      do_seek=0;
    }
    ogg_d->pos += ogg_d->last_size;
    ogg_d->last_size = 0;
    np = ogg_sync_pageseek(sync,page);

    if(np < 0)
      ogg_d->pos -= np;
    if(np <= 0) { // We need more data
      char* buf = ogg_sync_buffer(sync,BLOCK_SIZE);
      int len = stream_read(demuxer->stream,buf,BLOCK_SIZE);
       if(len == 0 && demuxer->stream->eof) {
	mp_msg(MSGT_DEMUX,MSGL_ERR,"EOF while trying to seek !!!!\n");
	break;
      }
      ogg_sync_wrote(sync,len);
      continue;
    }
    ogg_d->last_size = np;
    if(ogg_page_serialno(page) != oss->serialno)
      continue;

    if(ogg_stream_pagein(oss,page) != 0)
      continue;

     while(1) {
      np = ogg_stream_packetout(oss,&op);
      if(np < 0)
	continue;
      else if(np == 0)
	break;
      if (first) { /* Discard the first packet as it's probably broken,
           and we don't have any other means to decide whether it is
           complete or not. */
        first = 0;
        break;
      }
      is_gp_valid = (op.granulepos >= 0);
      demux_ogg_read_packet(os,&op,context,&pts,&is_keyframe,samplesize);
      if (precision && is_gp_valid) {
        precision--;
        if (abs(gp - op.granulepos) > rate && (op.granulepos != old_gp)) {
          //prepare another seek because we are off by more than 1s
          pos += (gp - op.granulepos) * (pos - old_pos) / (op.granulepos - old_gp);
          if (pos < 0) pos = 0;
          if (pos < (demuxer->movi_end - demuxer->movi_start)) {
            do_seek=1;
            break;
          }
        }
      }
      if (is_gp_valid && (pos > 0) && (old_gp > gp)
          && (2 * (old_gp - op.granulepos) < old_gp - gp)) {
        /* prepare another seek because looking for a syncpoint
           destroyed the backward search */
        pos = old_pos - 1.5 * (old_pos - pos);
        if (pos < 0) pos = 0;
        if (pos < (demuxer->movi_end - demuxer->movi_start)) {
          do_seek=1;
          break;
        }
      }
      if(!precision && (is_keyframe || os->vorbis) ) {
        ogg_sub.lines = 0;
        vo_sub = &ogg_sub;
        vo_osd_changed(OSDTYPE_SUBTITLE);
        clear_sub = -1;
	demux_ogg_add_packet(ds,os,ds->id,&op);
	if(sh_audio)
	  resync_audio_stream(sh_audio); 
	return;
      }
     }
  }

  mp_msg(MSGT_DEMUX,MSGL_ERR,"Can't find the good packet :(\n");  

}

void demux_close_ogg(demuxer_t* demuxer) {
  ogg_demuxer_t* ogg_d = demuxer->priv;
  int i;

  if(!ogg_d)
    return;

#ifdef USE_ICONV
  subcp_close();
#endif

  ogg_sync_clear(&ogg_d->sync);
  if(ogg_d->subs)
  {
    for (i = 0; i < ogg_d->num_sub; i++)
      ogg_stream_clear(&ogg_d->subs[i].stream);
    free(ogg_d->subs);
  }
  if(ogg_d->syncpoints)
    free(ogg_d->syncpoints);
  if (ogg_d->text_ids)
    free(ogg_d->text_ids);
  if (ogg_d->text_langs) {
    for (i = 0; i < ogg_d->n_text; i++)
      if (ogg_d->text_langs[i]) free(ogg_d->text_langs[i]);
    free(ogg_d->text_langs);
  }
  free(ogg_d);
}

int demux_ogg_control(demuxer_t *demuxer,int cmd, void *arg){
  ogg_demuxer_t* ogg_d = demuxer->priv;
  ogg_stream_t* os;
  float rate;

  if(demuxer->video->id >= 0) {
    os = &ogg_d->subs[demuxer->video->id];
    rate = os->samplerate;
  } else {
    os = &ogg_d->subs[demuxer->audio->id];
    rate = (float)((ov_struct_t*)((sh_audio_t*)demuxer->audio->sh)->context)->vi.rate;
  }


    switch(cmd) {
	case DEMUXER_CTRL_GET_TIME_LENGTH:
	    if (ogg_d->final_granulepos<=0) return DEMUXER_CTRL_DONTKNOW;
	    *((unsigned long *)arg)=ogg_d->final_granulepos / rate;
	    return DEMUXER_CTRL_GUESS;

	case DEMUXER_CTRL_GET_PERCENT_POS:
	    if (ogg_d->final_granulepos<=0) return DEMUXER_CTRL_DONTKNOW;
	    *((int *)arg)=(int)( (os->lastpos*100) / ogg_d->final_granulepos);
	    return DEMUXER_CTRL_OK;

	default:
	    return DEMUXER_CTRL_NOTIMPL;
    }
}

#endif