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Media Synchronization | MPEG-1 | |
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MPEG tables are groups
of structured information that describe programs, program components
or other information that is related to the delivery and decoding of programs.
There are many types of MPEG program tables and the more common tables contain
listings of programs in a transport channel (PAT), program components (video
and audio streams) and conditional access information (to enable decryption
and decoding).
Program specific information - PSI - is data that defines elements of characteristics of program media (such as the video, audio and meta descriptive components of a television program). A program allocation table - PAT - contains the identification codes and system information associated with programs that are contained in a transport stream. The PAT is usually sent every 20 msec to 100 msec to allow the receiver to quickly acquire a list of available programs. Program map table - PMT - contains information that identifies and describes the components (such as the video and audio elementary streams) that are parts of a program (such as a television show). A conditional access table - CAT - holds information that is used by an access device (such as a set top box with a smart card) to decode programs that are part of a conditional access system (e.g. on-demand programs). The CAT table provides the packet identifier (PID) channel code that provides the entitlement management messages (EMM) to the descrambler assembly. Private tables are user defined data elements that are sent along with broadcast programs (such as a television show). Electronic programming guides - EPG - may use information from program tables that p[rovide a customer to preview channel list to select from available content media. EPGs can vary from simple program selection to interactive filters that dynamically allow the user to filter through program guides by theme, time period, or other criteria. | ||
Introduction to MPEG This book explains the basics of audio and video digitization and compression and the standard formats that are used be MPEG. You will learn about the different MPEG audio coders and video coder options. $19.99 Printed, $16.99 eBook |