dvdnav.c

linux下的MPEG1

}

/*
 * These are the main get_next_block function which actually get the media stream video and audio etc.
 *
 * There are two versions: The second one is using the zero-copy read ahead cache and therefore
 * hands out pointers targetting directly into the cache.
 * The first one uses a memcopy to fill this cache block into the application provided memory.
 * The benefit of this first one is that no special memory management is needed. The application is
 * the only one responsible of allocating and freeing the memory associated with the pointer.
 * The drawback is the additional memcopy.
 */

dvdnav_status_t dvdnav_get_next_block(dvdnav_t *this, uint8_t *buf,
				      int32_t *event, int32_t *len) {
  unsigned char *block;
  dvdnav_status_t status;
  
  block = buf;
  status = dvdnav_get_next_cache_block(this, &block, event, len);
  if (status == DVDNAV_STATUS_OK && block != buf) {
    /* we received a block from the cache, copy it, so we can give it back */
    memcpy(buf, block, DVD_VIDEO_LB_LEN);
    dvdnav_free_cache_block(this, block);
  }
  return status;
}
 
dvdnav_status_t dvdnav_get_next_cache_block(dvdnav_t *this, uint8_t **buf,
					    int32_t *event, int32_t *len) {
  dvd_state_t *state;
  int32_t result;

  if(!this || !event || !len || !buf || !*buf) {
    printerr("Passed a NULL pointer.");
    return DVDNAV_STATUS_ERR;
  }

  pthread_mutex_lock(&this->vm_lock);
  
  if(!this->started) {
    /* Start the VM */
    if (!vm_start(this->vm)) {
      printerr("Encrypted or faulty DVD");
      return DVDNAV_STATUS_ERR;
    }
    this->started = 1;
  }

  state = &(this->vm->state);
  (*event) = DVDNAV_NOP;
  (*len) = 0;
 
  /* Check the STOP flag */
  if(this->vm->stopped) {
    vm_stop(this->vm);
    (*event) = DVDNAV_STOP;
    this->started = 0;
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  vm_position_get(this->vm, &this->position_next);
  
#ifdef LOG_DEBUG
  fprintf(MSG_OUT, "libdvdnav: POS-NEXT ");
  vm_position_print(this->vm, &this->position_next);
  fprintf(MSG_OUT, "libdvdnav: POS-CUR  ");
  vm_position_print(this->vm, &this->position_current);
#endif

  /* did we hop? */
  if(this->position_current.hop_channel != this->position_next.hop_channel) {
    (*event) = DVDNAV_HOP_CHANNEL;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: HOP_CHANNEL\n");
#endif
    if (this->position_next.hop_channel - this->position_current.hop_channel >= HOP_SEEK) {
      int32_t num_angles = 0, current;
      
      /* we seeked -> check for multiple angles */
      vm_get_angle_info(this->vm, &current, &num_angles);
      if (num_angles > 1) {
        int32_t result, block;
	/* we have to skip the first VOBU when seeking in a multiangle feature,
	 * because it might belong to the wrong angle */
	block = this->position_next.cell_start + this->position_next.block;
	result = dvdnav_read_cache_block(this->cache, block, 1, buf);
	if(result <= 0) {
	  printerr("Error reading NAV packet.");
	  pthread_mutex_unlock(&this->vm_lock); 
	  return DVDNAV_STATUS_ERR;
	}
	/* Decode nav into pci and dsi. Then get next VOBU info. */
	if(!dvdnav_decode_packet(this, *buf, &this->dsi, &this->pci)) {
	  printerr("Expected NAV packet but none found.");
	  pthread_mutex_unlock(&this->vm_lock); 
	  return DVDNAV_STATUS_ERR;
	}
	dvdnav_get_vobu(this, &this->dsi, &this->pci, &this->vobu);
	/* skip to next, if there is a next */
	if (this->vobu.vobu_next != SRI_END_OF_CELL) {
	  this->vobu.vobu_start += this->vobu.vobu_next;
	  this->vobu.vobu_next   = 0;
	}
	/* update VM state */
	this->vm->state.blockN = this->vobu.vobu_start - this->position_next.cell_start;
      }
    }
    this->position_current.hop_channel = this->position_next.hop_channel;
    /* update VOBU info */
    this->vobu.vobu_start  = this->position_next.cell_start + this->position_next.block;
    this->vobu.vobu_next   = 0;
    /* Make blockN == vobu_length to do expected_nav */
    this->vobu.vobu_length = 0;
    this->vobu.blockN      = 0;
    this->sync_wait        = 0;
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  /* Check the HIGHLIGHT flag */
  if(this->position_current.button != this->position_next.button) {
    dvdnav_highlight_event_t *hevent = (dvdnav_highlight_event_t *)*buf;

    (*event) = DVDNAV_HIGHLIGHT;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: HIGHLIGHT\n");
#endif
    (*len) = sizeof(dvdnav_highlight_event_t);
    hevent->display = 1;
    hevent->buttonN = this->position_next.button;
    this->position_current.button = this->position_next.button;
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }
  
  /* Check the WAIT flag */
  if(this->sync_wait) {
    (*event) = DVDNAV_WAIT;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: WAIT\n");
#endif
    (*len) = 0;
    pthread_mutex_unlock(&this->vm_lock);
    return DVDNAV_STATUS_OK;
  }

  /* Check to see if we need to change the currently opened VOB */
  if((this->position_current.vts != this->position_next.vts) || 
     (this->position_current.domain != this->position_next.domain)) {
    dvd_read_domain_t domain;
    int32_t vtsN;
    dvdnav_vts_change_event_t *vts_event = (dvdnav_vts_change_event_t *)*buf;
    
    if(this->file) {
      DVDCloseFile(this->file);
      this->file = NULL;
    }

    vts_event->old_vtsN = this->position_current.vts;
    vts_event->old_domain = this->position_current.domain;
     
    /* Use the DOMAIN to find whether to open menu or title VOBs */
    switch(this->position_next.domain) {
    case FP_DOMAIN:
    case VMGM_DOMAIN:
      domain = DVD_READ_MENU_VOBS;
      vtsN = 0;
      break;
    case VTSM_DOMAIN:
      domain = DVD_READ_MENU_VOBS;
      vtsN = this->position_next.vts; 
      break;
    case VTS_DOMAIN:
      domain = DVD_READ_TITLE_VOBS;
      vtsN = this->position_next.vts; 
      break;
    default:
      printerr("Unknown domain when changing VTS.");
      pthread_mutex_unlock(&this->vm_lock); 
      return DVDNAV_STATUS_ERR;
    }
    
    this->position_current.vts = this->position_next.vts; 
    this->position_current.domain = this->position_next.domain;
    dvdnav_read_cache_clear(this->cache);
    this->file = DVDOpenFile(vm_get_dvd_reader(this->vm), vtsN, domain);
    vts_event->new_vtsN = this->position_next.vts; 
    vts_event->new_domain = this->position_next.domain; 

    /* If couldn't open the file for some reason, moan */
    if(this->file == NULL) {
      printerrf("Error opening vtsN=%i, domain=%i.", vtsN, domain);
      pthread_mutex_unlock(&this->vm_lock); 
      return DVDNAV_STATUS_ERR;
    }

    /* File opened successfully so return a VTS change event */
    (*event) = DVDNAV_VTS_CHANGE;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: VTS_CHANGE\n");
#endif
    (*len) = sizeof(dvdnav_vts_change_event_t);

    this->spu_clut_changed = 1;
    this->position_current.cell = -1; /* Force an update */
    this->position_current.spu_channel = -1; /* Force an update */
    this->position_current.audio_channel = -1; /* Force an update */;
     
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  /* Check if the cell changed */  
  if( (this->position_current.cell != this->position_next.cell) ||
      (this->position_current.cell_restart != this->position_next.cell_restart) ||
      (this->position_current.cell_start != this->position_next.cell_start) ) {
    dvdnav_cell_change_event_t *cell_event = (dvdnav_cell_change_event_t *)*buf;
    int32_t first_cell_nr, last_cell_nr, i;
    dvd_state_t *state = &this->vm->state;
    
    (*event) = DVDNAV_CELL_CHANGE;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: CELL_CHANGE\n");
#endif
    (*len) = sizeof(dvdnav_cell_change_event_t);
    
    cell_event->cellN = state->cellN;
    cell_event->pgN   = state->pgN;
    cell_event->cell_length =
      dvdnav_convert_time(&state->pgc->cell_playback[state->cellN-1].playback_time);

    cell_event->pg_length = 0;
    /* Find start cell of program. */
    first_cell_nr = state->pgc->program_map[state->pgN-1];
    /* Find end cell of program */
    if(state->pgN < state->pgc->nr_of_programs)
      last_cell_nr = state->pgc->program_map[state->pgN] - 1;
    else
      last_cell_nr = state->pgc->nr_of_cells;
    for (i = first_cell_nr; i <= last_cell_nr; i++)
      cell_event->pg_length +=
        dvdnav_convert_time(&state->pgc->cell_playback[i - 1].playback_time);
    cell_event->pgc_length = dvdnav_convert_time(&state->pgc->playback_time);

    cell_event->cell_start = 0;
    for (i = 1; i < state->cellN; i++)
      cell_event->cell_start +=
        dvdnav_convert_time(&state->pgc->cell_playback[i - 1].playback_time);

    cell_event->pg_start = 0;
    for (i = 1; i < state->pgc->program_map[state->pgN-1]; i++)
      cell_event->pg_start +=
        dvdnav_convert_time(&state->pgc->cell_playback[i - 1].playback_time);

    this->position_current.cell         = this->position_next.cell;
    this->position_current.cell_restart = this->position_next.cell_restart;
    this->position_current.cell_start   = this->position_next.cell_start;
    this->position_current.block        = this->position_next.block;
    
    /* vobu info is used for mid cell resumes */
    this->vobu.vobu_start               = this->position_next.cell_start + this->position_next.block;
    this->vobu.vobu_next                = 0;
    /* Make blockN == vobu_length to do expected_nav */
    this->vobu.vobu_length = 0;
    this->vobu.blockN      = 0;
    
    /* update the spu palette at least on PGC changes */
    this->spu_clut_changed = 1;
    this->position_current.spu_channel = -1; /* Force an update */
    this->position_current.audio_channel = -1; /* Force an update */

    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }
 
  /* has the CLUT changed? */
  if(this->spu_clut_changed) {
    (*event) = DVDNAV_SPU_CLUT_CHANGE;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: SPU_CLUT_CHANGE\n");
#endif
    (*len) = 16 * sizeof(uint32_t);
    memcpy(*buf, &(state->pgc->palette), 16 * sizeof(uint32_t));
    this->spu_clut_changed = 0;
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  /* has the SPU channel changed? */  
  if(this->position_current.spu_channel != this->position_next.spu_channel) {
    dvdnav_spu_stream_change_event_t *stream_change = (dvdnav_spu_stream_change_event_t *)*buf;

    (*event) = DVDNAV_SPU_STREAM_CHANGE;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: SPU_STREAM_CHANGE\n");
#endif
    (*len) = sizeof(dvdnav_spu_stream_change_event_t);
    stream_change->physical_wide      = vm_get_subp_active_stream(this->vm, 0);
    stream_change->physical_letterbox = vm_get_subp_active_stream(this->vm, 1);
    stream_change->physical_pan_scan  = vm_get_subp_active_stream(this->vm, 2);
    this->position_current.spu_channel = this->position_next.spu_channel;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: SPU_STREAM_CHANGE stream_id_wide=%d\n",stream_change->physical_wide);
    fprintf(MSG_OUT, "libdvdnav: SPU_STREAM_CHANGE stream_id_letterbox=%d\n",stream_change->physical_letterbox);
    fprintf(MSG_OUT, "libdvdnav: SPU_STREAM_CHANGE stream_id_pan_scan=%d\n",stream_change->physical_pan_scan);
    fprintf(MSG_OUT, "libdvdnav: SPU_STREAM_CHANGE returning DVDNAV_STATUS_OK\n");
#endif
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  /* has the audio channel changed? */  
  if(this->position_current.audio_channel != this->position_next.audio_channel) {
    dvdnav_audio_stream_change_event_t *stream_change = (dvdnav_audio_stream_change_event_t *)*buf;
    
    (*event) = DVDNAV_AUDIO_STREAM_CHANGE;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: AUDIO_STREAM_CHANGE\n");
#endif
    (*len) = sizeof(dvdnav_audio_stream_change_event_t);
    stream_change->physical = vm_get_audio_active_stream( this->vm );
    this->position_current.audio_channel = this->position_next.audio_channel;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: AUDIO_STREAM_CHANGE stream_id=%d returning DVDNAV_STATUS_OK\n",stream_change->physical);
#endif
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }
     
  /* Check the STILLFRAME flag */
  if(this->position_current.still != 0) {
    dvdnav_still_event_t *still_event = (dvdnav_still_event_t *)*buf;

    (*event) = DVDNAV_STILL_FRAME;
#ifdef LOG_DEBUG
    fprintf(MSG_OUT, "libdvdnav: STILL_FRAME\n");
#endif
    (*len) = sizeof(dvdnav_still_event_t);
    still_event->length = this->position_current.still;
    pthread_mutex_unlock(&this->vm_lock); 
    return DVDNAV_STATUS_OK;
  }

  /* Have we reached the end of a VOBU? */
  if (this->vobu.blockN >= this->vobu.vobu_length) {

    /* Have we reached the end of a cell? */
    if(this->vobu.vobu_next == SRI_END_OF_CELL) {
      /* End of Cell from NAV DSI info */
#ifdef LOG_DEBUG
      fprintf(MSG_OUT, "libdvdnav: Still set to %x\n", this->position_next.still);
#endif
      this->position_current.still = this->position_next.still;

      /* we are about to leave a cell, so a lot of state changes could occur;
       * under certain conditions, the application should get in sync with us before this,
       * otherwise it might show stills or menus too shortly */
      if ((this->position_current.still || this->pci.hli.hl_gi.hli_ss) && !this->sync_wait_skip) {
        this->sync_wait = 1;
      } else {
	if( this->position_current.still == 0 || this->skip_still ) {