IEC 61883-7 pdf download Consumer audio/video equipment – Digital interface – Part 7: Transmission of ITU-R BO.1294 System B
1 scope
This specification defines packetization and transmission for transport streams of lTU-R B0.1294system B (DirecTV system/Dss) over the lEEE 1394 Serial Bus.
2Normative references
The following referenced documents are indispensable for the application of this document.For dated references, only the edition cited applies.For undated references, the latest editionof the referenced document (including any amendments) applies.
IEC 61883-1,Consumer audio/video equipment – Digital interface – Part 1: General
ITU-R BO.1294:1997,Common functional requirements for the reception of digital multi-programme television emissions by satellites operating in the 11/12 GHz frequency range1
IEEE 1394:1995,Standard for a High Performance Serial Bus
IEEE 1394a:2000, Standard for a High Performance Serial Bus – Amendment 1
3 Terms, definitions and abbreviations
For the purposes of this part of lEC 61883, the following terms and definitions apply.
3.1 Terms and definitions
For the purposes of this part of lEC 61883, the following terms and definitions apply.
3.1.1
byte
eight bits of data, used as a synonym for octetNOTE The symbol for byte is B.
3.1.2
cSR architecture
convenient abbreviation of the following reference: ISO/IEC 13213:1994,Informationtechnology – Microprocessor systems – Control and status register (CSR) architecture formicrocomputer buses
3.1.3
quadlet
four bytes of data
3.2 Abbreviations
For the purpose of this part of IEC 61 883, the following abbreviations used in IEEE 1 394
apply:
AV/C Audio Video Control
CIP Common Isochronous Packet
CTR Cycle Time Register
HD High Definition
IEEE The Institute of Electrical and Electronics Engineers, Inc.
MPEG Motion Picture Expert Group
TSP Transport Stream Package
4 DSS transport stream
A DSS transport stream consists of transport stream packets with a length of 1 30 B.
NOTE Refer to Annex 1 of ITU-R BO.1 294: 1 997 for more information.
A stream may contain several programs. In Figure 1 , an example is given of a transport stream, which consists of several programs. Often, only one or a few programs need to be transmitted. If a program selection is carried out, then only those transport stream packets from that particular transport stream are transmitted. In this situation, the occupied bandwidth on the IEEE 1 394 interface can be reduced. Reduction of the bit rate is carried in a smoothing buffer. As a result of the smoothing operation, the transport stream packets will be shifted in time.
The transport stream packets at the output of the smoothing buffer are transmitted over the IEEE 1 394 interface.
During transmission, this interface will introduce some jitter on the arrival time of the transport stream packets in the receiver. In the DSS transport stream, there are strong requirements on the timing of the transport stream packets. The jitter introduced by the both the smoothing buffer and the transmitter of the interface has to be compensated. This is done by adding a time stamp to the transport stream packets:
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