Event information table

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The Event Information Table ( EIT ; German broadcast information table ) is a table that contains information about current and planned broadcasts (events) in digital television ( DVB ). Data from the EIT are used for electronic program guides (EPG) and time-controlled recordings. It is part of DVB-SI and specified in accordance with ETSI EN 300 468.

The EIT contains information for programs (services) in the received and also in other transport streams. It is sent out in packets with the PID 18.

construction

The EIT is often the largest table in an MPEG transport stream because it contains a lot of information in a readable form. The key term in this table is the event that describes an individual program (e.g. “Tagesschau”). Unlike most of the other service information tables , the information is broken down into several sub-tables, each with its own table identification (Table_ID).

There can be four classes of single tables

  1. Table with table_id 0x4E contains information about the current and the following transmission of the received transport stream
  2. Table with table_id 0x4F contains information about the current and the following transmission of further transport streams
  3. Tables with table_id from 0x50 to 0x5F contain information about the planned transmission of the received transport stream
  4. Tables with table_id from 0x60 to 0x6F contain information about the planned transmission of further transport streams

Each section (which contains a maximum of 4 kilobytes of binary data) contains the following information:

  • Table identification (table_id) and table identification of the last table (last_table_id) in this table set.
  • Program identification (Service_id).
  • Number of the section and indication of the last section, whereby the first section always has the number 0 and the numbering must be in ascending order, but not without gaps. In the latter case, the information of the number of the last section in this segment is still available. This is often used to organize the transmissions over time.
  • Transport stream identification (transport_stream_id) and network identification (original_network_id).
  • Information about one or more mailings with the following detailed data:
    • Broadcast identification (event_id).
    • Start time of transmission (start_time).
    • Duration of the transmission.
    • Status of the transmission (running_status), u. a. "Does not work", "starts in a few seconds" "runs". This information can be used for automatic recording control.
    • Transmission can be received freely (i.e. not encrypted) (free_CA_mode).
    • Further broadcast-dependent information that is held in descriptors . These are u. a .:
      • Brief description of the broadcast (short_event_descriptor) including the title.
      • Detailed description of the broadcast (extended_event_descriptor). Since a descriptor cannot be longer than 255 characters, several of these descriptors can be used to form longer texts.
      • Category of broadcast (e.g. crime thriller, documentary, news).

The table 0x4E assigned to the program, which only contains information about these two broadcasts (events), is used to determine the program currently being broadcast and the subsequent broadcast of a program (service) in the currently received transport stream.

The scope of the overall table is explained by the possibility of combining the fields table identification (table_id), program identification (Service_id), transport stream identification (transport_stream_id) and network identification (original_network_id). For a typical transport stream in Germany, with four programs (services), in which only broadcasts of the received transport stream are regularly displayed, around 500 different sections can be received.

The time interval between the individual sections in the transport stream is between 2 seconds (for the current and subsequent broadcast in the received transport stream) and a maximum of 5 minutes (for planned broadcasts in other transport streams).

Individual evidence

  1. ↑ ETSI: Digital Video Broadcasting (DVB); Specification for Service Information (SI) in DVB systems , chapter 5.2.4 Event Information Table (EIT) . Retrieved April 16, 2015
  2. ↑ ETSI: Digital Video Broadcasting (DVB); Measurement guidelines for DVB systems . Chapter 5.2.3 eit_error . Retrieved April 16, 2015

literature

  • Digital video broadcasting (DVB); Guidelines on implementation and usage of Service Information (SI) . ETSI TS 101 211 V1.11.1 (2012-04); Reference: RTS / JTC-DVB-313.
  • Digital video broadcasting (DVB); Specification for Service Information (SI) in DVB systems . ETSI EN 300 468 V1.13.1 (2012-04); Reference: REN / JTC-DVB-314.
  • International Electrotechnical Commission 2001; IEC 62216-1, E-Book V2.0.2
  • Gil Solla, Alberto / Sotelo Bovino, Rafael G .: TV-Anytime Paving the Way for Personalized TV. Springer, Berlin (2013).

See also

Web links