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1、BROADCASTING DIVISIONAPPLICATION NOTEThe most common abbreviations used in the standards for digital TV: MPEG2, DVB and ATSCProducts:MPEG2 DTV RECORDER GENERATORDVRG MPEG2 MEASUREMENT GENERATORDVG MPEG2 REAL TIME MONITORDVRM MPEG2 MEASUREMENT DECODERDVMDQAM TEST RECEIVER/DEMODULATOREFA TV TEST TRANS
2、MITTERSFQ7BM27_0EBROADCASTING DIVISION21 MPEG2 AbbreviationsAdaptation Field Ancillary program data (especially PCR) which are uncoded and are transmitted at least every 100ms acc. to MPEG2 or 40 ms acc. to DVB specifications BATBouquet Association Table Table describing a bouquet of programs offere
3、d by a broadcasterBlock8x8 pixel block, MPEG2 codedCAConditional AccessInformation of whether the program is scrambledCATConditional Access Table (PID=1): Reference to scrambled programsCIFCommon Intermediate Format Picture formatCRCCyclic Redundancy CheckDCTDiscrete Cosine TransformDCT-1 / IDCTInve
4、rse Discrete Cosine TransformDFDDisplaced Frame Difference Differential picture if there is motionDPCMDifferential Pulse Code ModulationDTSDecoding Time Stamp Stamp for decoding time, only transmitted if not identical with PTS; reference to PIDEITEvent Information Table TV guideESElementary Stream C
5、ompressed data stream for video, audio or data. Preliminary stage to PESGOPGroup of PicturesI, P, and B pictures Intra-coded pictures (I), predicted pictures (P) and bi- directional prediction pictures (B)IRDIntegrated Receiver Decoder Receiver with (MPEG) decoder MPEGMotion Picture Experts Group so
6、metimes called Moving Picture Experts GroupMUSICAMMasking Pattern Adapted Universal Subband Integra- ted Coding and Multiplexing Compression method for audio codingThe most common abbreviations used in the standards for digital TV: MPEG2, DVB and ATSCThe introduction of the transmission of compresse
7、d TV signals to MPEG2 and DVB for cable, satellite and terrestrial (COFDM) lead to the creation of many abbreviations that have to be explained to the “uninitiated”. In the previous three lines, three abbreviations whose meanings are not obvious have already been mentioned. A table explaining what t
8、hese abbreviations mean is therefore essential.BROADCASTING DIVISION3NITNetwork Information Table Information about orbit, transponder etc.PATProgram Association Table (PID=0): List of all the programs contained in TS Multiplex with reference to PID of PMTPay LoadUseful data in TSPCMPulse Code Modul
9、ationPCRProgram Clock Reference Reference in TS for the 27-MHz clock recovery. Transmitted at least every 0.1 secPESPacketized Elementary Stream Video and audio data packets and ancillary data of definable lengthPES Header Ancillary data for an elementary streamPIDPacket Identification Identificatio
10、n of programs in the transport streamPMTProgram Map Table: Reference to packets with PCR Name of programs, copyright, reference of the data streams with PIDs etc. belonging to the relevant programPredictionPrediction of a picture (P or B) with indication of a motion vectorProfileSubdivision of video
11、 coding into different resolutionsPSProgram Stream Multiplex of several audio and video PES using the same clock. PSIProgram Specific Informa- tion Data transmitted in TS for the demultiplexer in the receiver (eg PAT, PMT, CAT)PTSPresentation Time Stamp Time stamp for vision and sound, transmitted a
12、t least every 0.7 sec. Integrated into PESQQuantizationQ-1 Inverse quantizationQSQuantization scalingRLCRun Length Coding Coding of data with different number of bits. Frequently reoccurring data has the smallest number of bits, data seldom reoccurring have the highest number of bits.RSTRunning Stat
13、us Table Accurate and fast adaptation to a new program run if time changes occur in the scheduleSectionA table is subdivided into several sections. If there is a change, only the section affected is transmittedSIService Information All the data required by the receiver to demultiplex and decode the
14、various programs in the TSSIFSource Input FormatSCRSystem Clock Reference Reference in ES for synchro- nizing the system demultiplex clock in the receiver, transmitted at least every 0.7 sec. Integrated into PESSDTService Description Table Description of programs offeredSTCSystem Time Clock 27-MHz c
15、lock, regenerated from PCR for a jitter-free readout of MPEG dataBROADCASTING DIVISION4SYNC(_byte)Synchronization byte in TS header value 0x47TSTransport StreamTS HeaderThe first 4 bytes of each TS packet contain the data (PID) required for the demultiplexer in addition to the sync byte (0x47). Thes
16、e bytes are never scrambled.TDTTime and Date table UTC time and dateTOTTime Offset Table UTC time and date with indication of local time offsetUTCUniversal Time, Co- ordinated Greenwich meantimeVBR Variable Bit RateVLCVariable Length Coding Coding of data with variable number of bits (also see RLC)ZigZag ScanZigzag scan of quantized DCT coeffi- cient matrix. This gives an efficient run length
