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PSI/PSIP Table Analysis
Like the SI tables, DVB & ATSC also provide PSIP (Program and System Information Protocol) tables.
PSIP stands for "program and system information protocol" and represents a similar store of information to
that given on DVB SI. In ATSC, the following tables are used: the Master Guide Table (MGT), the Event
Information Table (EIT), the Extended Text Table (ETT), the System Time Table (STT), the Rating Region Table
(RRT), and the Cable Virtual Channel Table (CVCT) or the Terrestrial Virtual Channel Table (TVCT).
According to ATSC, the PSI tables defined in MPEG-2 and provided in the MPEG Standard are used for
accessing the video and audio streams, i.e. the transport stream carries one PAT and several PMTs. The
conditional access information is also referenced via a CAT.
The actual ATSC tables are implemented as “private tables”. The Master Guide Table, contains the PIDs for
some of these ATSC tables. The Master Guide Table can be recognized by the packet ID = 0x1FFB and the
table ID = 0xC7. The transport stream must contain at least four Event Information Tables (EIT-0, EIT-1, EIT-2,
EIT-3) and the PIDs for these EITs are found in the Master Guide Table. Up to 128 further Event Information
Tables are possible but also optional. An EIT contains a 3-hour section of an electronic program guide
(EPG). Together with the 4 mandatory EITs, it is possible to cover a period of 12 hours. Furthermore, Extended
Text Tables may optionally be accessed through the MGT. Each existing Extended Text Table (ETT) is
allocated to one EIT. Thus, e.g. ETT-0 contains extended text information for EIT- 0. It is possible to have up to
a total of 128 ETTs.
PSIP Table ID Ranges and Value
Table PID Table ID Value (hex)
Program Association Table (PAT) 0x0 0x0
Program Map Table (PMT) per PAT 0x2
Conditional Access Table (CAT) 0x1 0x1
Master Guide Table (MGT) 0x1FFB 0xC7
Terrestrial Virtual Channel Table
(TVCT)
0x1FFB 0xC8
Cable Virtual Channel Table (CVCT)
0x1FFB 0Xc9
Rating Region Table (RRT) 0x1FFB 0xCA
Event Information Table (EIT) per MGT 0xCB
Extended Text Table (ETT) per MGT 0xCC
System Time Tables (STT) 0x1FFB 0xCD
In the Virtual Channel Table, which can be present either as Terrestrial Virtual Channel Table (TVCT) or as
Cable Virtual Channel Table (CVCT) depending on the transmission path, identification information for the
virtual channels, i.e. programs, contained in a multiplexed transport stream are transmitted. The VCT
contains, among other things, the program names. The VCT is thus comparable to the SDT table in DVB.
In the System Time Table (STT), all the necessary time information is transmitted. The STT can be recognized
by the packet ID = 0x1FFB and the table ID = 0xCD. In the STT, the GPS (Global Positioning System) time and
the time difference between GPS time and UTC (Universal Time Coordinated (= GMT)) is transmitted. The
Rating Region Table (RRT) can be used for restricting the size of the audience in terms of age or region. In
addition to the information about region (e.g. a Federal State in the US), information relating to the
minimum age set for the program currently being broadcast is also included. Using the RRT, a type of
parental lock can be implemented in the set-top box. The RRT is recognized by the packet ID = 0x1FFB and
the table ID = 0xCA.
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