Program Specific Information

Program Specific Information

Program Specific Information (PSI) is metadata, part of MPEG transport stream.

The PSI data contains four tables: PAT (Program Association Table), CAT (Conditional Access Table), PMT (Program Map Table) and NIT (Network Information Table). This last table is normally not used with MPEG-2 PSI.

PSI is carried in the form of a table structure. The table structure can span multiple transport stream packets. Adaptation field also occurs in TS packets carrying PSI data. The PSI data will never be scrambled so that the decoder at the receiving end can easily identify the properties of the stream.

The PSI data contains five tables: * PAT (Program Association Table) * CAT (Conditional Access Table) * PMT (Program Map Table) * NIT (Network Information Table) * TDT (Time and Date Table)

Some tables are associated with predefined PID as explained in the respective sections.And each table has predefined structure.

PAT (Program Association Table)

The PAT is assigned PID 0x0000 and table id of 0x00. The transport stream contains at least one or more TS packets with PID 0x0000. Some of these consecutive packets form the PAT.At the decoder side the PSI [http://mhpkdbwiki.s3.uni-due.de/mhpkdbwiki/index.php/Section_Filtering section filter] listens to the incoming TS packets. After the filter identifies the PAT table they assemble the packet and decode it.A PAT has information about all the programs contained in the TS. The PAT contains information showing the association of Program Map Table PID and Program Number.

CAT (Conditional Access Table)

This table is used for conditional access to the streams. This table provides association with EMM stream. When the TS is scrambled then this section contains the EMM PID. This EMM pid is encrypted using the smart card number.

PMT (Program Map Table)

This table contains PID numbers of elementary streams associated with the program. In addition it also contains the encrypted messages ECM. The table has information about the type of elementary stream.

NIT (Network Information Table)

This table provides information about the multiplexes and transport streams on a given network.

Information about the current network uses table_id of 0x40, that about other networks uses table_id of 0x41.

It is segmented into network information sections and is carried on PID 0x0010. [ref EN300468]

Also this table contains the private stream information too. For example, TeleText, Subtitle and MHEG

TDT (Time and Date Table)

Provides UTC (Universal Time) coded as MJD (Modified Julian Date). The PID value is 0x0014.

For TDT - Table ID is 0x70For TOT - Table ID is 0x73

References

External links

* [http://www.dunod.com/documents/49346/49346_DVB.pdf DVB system information chart]
* [http://www.av.it.pt/research/rmom/dtv/PDFfiles/present/DTV_ICP_ch4.pdf mpeg-2 DVB]


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Information — as a concept has a diversity of meanings, from everyday usage to technical settings. Generally speaking, the concept of information is closely related to notions of constraint, communication, control, data, form, instruction, knowledge, meaning,… …   Wikipedia

  • Program evaluation — is a formalized approach to studying the goals, processes, and impacts of projects, policies and programs. Program evaluation is used in the public and private sector and is taught in numerous universities. Evaluation became particularly relevant …   Wikipedia

  • Site-specific information DSM program assistance —   ADSM (demand side management) assistance program that provides guidance on energy efficiency and load management options tailored to a particular customer s facility; it often involves an on site inspection of the customer facility to identify… …   Energy terms

  • information system — Introduction       an integrated set of components for collecting, storing, processing, and communicating information (information science). Business firms, other organizations, and individuals in contemporary society rely on information systems… …   Universalium

  • information processing — Acquisition, recording, organization, retrieval, display, and dissemination of information. Today the term usually refers to computer based operations. Information processing consists of locating and capturing information, using software to… …   Universalium

  • Information warfare — Warfare Military history Eras Prehistoric Ancient Medieval Gunpowder Industrial …   Wikipedia

  • Information model — An information model in software engineering is a representation of concepts, relationships, constraints, rules, and operations to specify data semantics for a chosen domain of discourse. It can provide sharable, stable, and organized structure… …   Wikipedia

  • Information Awareness Office — seal The Information Awareness Office (IAO) was established by the Defense Advanced Research Projects Agency (DARPA) in January 2002 to bring together several DARPA projects focused on applying surveillance and information technology to track and …   Wikipedia

  • Information security — Components: or qualities, i.e., Confidentiality, Integrity and Availability (CIA). Information Systems are decomposed in three main portions, hardware, software and communications with the purpose to identify and apply information security… …   Wikipedia

  • Information technology governance — Information Technology Governance, IT Governance or ICT (Information Communications Technology) Governance, is a subset discipline of Corporate Governance focused on information technology (IT) systems and their performance and risk management.… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”