1.1 Scope
This Part of GB/T 17975 specified the system layer of the coding. It was developed principally to support the combination of the video and audio coding methods defined in Part 2 and 3 of this Standard. The system layer supports six basic functions:
a) the synchronization of multiple compressed streams on decoding;
b) the interleaving of multiple compressed streams into a single stream;
c) the initialization of buffering for decoding start up;
d) continuous buffer management;
e) time identification;
A GB/T 17975.1 multiplexed bit stream is either a Transport Stream or a Program Stream. Both streams are constructed from PES packets and packets containing other necessary information. Both stream types support multiplexing of video and audio compressed streams from one program with a common time base. The Transport Stream additionally supports the multiplexing of video and audio compressed streams from multiple programs with independent time bases. For almost error-free environments the Program Stream is generally more appropriate, supporting software processing of program information. The Transport Stream is more suitable for use in environments where errors are likely.
A GB/T 17975.1 multiplexed bit stream, whether a Transport Stream or a Program Stream, is constructed in two layers: the outermost layer is the system layer, and the innermost is the compression layer. The system layer provides the functions necessary for using one or more compressed data streams in a system. The video and audio parts of GB/T 17975 define the compression coding layer for audio and video data. Coding of other types of data is not contained in this Specification, but is supported by the system layer provided that the other types of data adhere to the constraints on multiplexing stream semantics defined in Section 2.7.
1.2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding amending errors in the text) to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative documents referred to applies.
GB/T 4880.2-2000 Codes for the Presentations of Names of Languages C Part2: Alpha-3 Code (eqv ISO 639-2: 1998)
GB/T 15273.1-1994 Information Processing C 8-bit Single-byte Graphic Characters Sets C Part 1: Latin Alphabet No. 1 (idt ISO 8859-1: 1997)
GB/T 17191.1-1997 Information Technology C Coding of Moving Pictures and Associated Audio for Digital Storage Media at up to about 1.5Mbit/s C Part 1: Systems (idt ISO/IEC 11172-1: 1993)
GB/T 17191.2-1997 Information Technology C Coding of Moving Pictures and Associated Audio for Digital Storage Media at up to about 1.5Mbit/s C Part 2: Video (idt ISO/IEC 11172-2: 1993)
GB/T 17191.3-1997 Information Technology C Coding of Moving Pictures and Associated Audio for Digital Storage Media at up to about 1.5Mbit/s C Part 2: (idt ISO/IEC 11172-3: 1993)
GB/T 17576-1998 Compact Disc Digital Audio System (idt IEC 908: 1987)
GB/T 17975.2-2000 Information Technology C Generic Coding of Moving Picture and Associated Audio Information C Part 2: Video (idt ITU-T H: 262: 1995)
GB/T 17975.3-2002 Information Technology C Generic Coding of Moving Picture and Associated Audio Information C Part 3: Audio (idt ISO/IEC 13818-3: 1998)
GB/T 20090.2-2006 Information Technology Advanced Coding of Audio and Video C Part 2: Video
ISO/IEC 13818-2: 2000 Information Technology C Generic Coding of Moving Pictures and Associated Audio Information: Video
ISO/IEC 13818-3: 1998 Information Technology C Generic Coding of Moving Pictures and Associated Audio Information: Audio
ISO/IEC 13522-1:1997 Information Technology C Coding of Multimedia and Hypermedia Information C Part 1: MHEG Object Representation C Base Notation (ASN.1)
ITU-R Recommendation BT.601.3 Studio Encoding Parameters of Digital Television ITU-R Recommendation BT.470-2 Television System
ITU-R BR.648 Digital Recording of Audio Signal
ITU-R Report BO.955.2 Satellite Sound Broadcasting to Vehicular, Portable and Fixed Receivers in the Range of 500-3000 MHz
CCITT Recommendation J.17 (1988) Pre-emphasis Circuits used on Sound-programme
2 Technical Elements
GB/T 17975.1-2010 The following standards are cited：
