Digital Audio Broadcasting (DAB); Multimedia Object Transfer (MOT) protocol

To produce edition 2 simply by the addition of a directory object to provide effective file management. The amendment will be backwards compatible with the existing standard. The group working with the MOT updates within Eureka 147 will be refered to as Task Force Directory Object, in short TF DO. Rapporteur: Richard Rebhan, Teracom, Sweden Supporting organisations: Eureka 147 members.

Digitalna zvokovna radiodifuzija (DAB) - Protokol za prenos multimedijskih objektov (MDT)

General Information

Status
Published
Publication Date
31-Dec-1999
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Jan-2000
Due Date
01-Jan-2000
Completion Date
01-Jan-2000

Buy Standard

Standard
EN 301 234:2000
English language
31 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digitalna zvokovna radiodifuzija (DAB) - Protokol za prenos multimedijskih objektov (MDT)Digital Audio Broadcasting (DAB); Multimedia Object Transfer (MOT) protocol33.160.60WHOHNRQIHUHQFHMultimedia systems and teleconferencing equipmentICS:Ta slovenski standard je istoveten z:EN 301 234 Version 1.2.1SIST EN 301 234:2000en01-januar-2000SIST EN 301 234:2000SLOVENSKI
STANDARD



SIST EN 301 234:2000



EN 301 234 V1.2.1 (1999-02)European Standard (Telecommunications series)Digital Audio Broadcasting (DAB);Multimedia Object Transfer (MOT) protocolEBUUEREuropean Broadcasting UnionUnion Européenne de Radio-TélévisionSIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)2ReferenceREN/JTC-DAB-MOT-1 (bfc00ioo.PDF)KeywordsDAB, digital, audio, broadcasting, multimedia,protocolETSIPostal addressF-06921 Sophia Antipolis Cedex - FRANCEOffice address650 Route des Lucioles - Sophia AntipolisValbonne - FRANCETel.: +33 4 92 94 42 00
Fax: +33 4 93 65 47 16Siret N° 348 623 562 00017 - NAF 742 CAssociation à but non lucratif enregistrée à laSous-Préfecture de Grasse (06) N° 7803/88Internetsecretariat@etsi.frIndividual copies of this ETSI deliverablecan be downloaded fromhttp://www.etsi.orgIf you find errors in the present document, send yourcomment to: editor@etsi.frCopyright NotificationNo part may be reproduced except as authorized by written permission.The copyright and the foregoing restriction extend to reproduction in all media.© European Telecommunications Standards Institute 1999.© European Broadcasting Union 1999.All rights reserved.SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)3ContentsIntellectual Property Rights.5Foreword.51Scope.62References.63Definitions and abbreviations.83.1Definitions.83.2Abbreviations.94General description of the MOT protocol.104.1Requirements of Multimedia services.104.2Problems MOT is attempting to solve.104.3Receiver architecture reference model.115Object description.125.1Header core.125.2Header extension.135.2.1Structure of the header extension.145.2.2Future expansion of the parameter data field.155.2.3Parameters of the header extension.155.3Object body.176Object transport mechanisms.186.1Segmentation of objects - transport level.196.1.1Segmentation header.206.1.2Transport of header segments.206.1.3Transport of body segments.206.2Packetizing segments - network level.216.2.1Packet mode.216.2.2X-PAD.216.2.2.1Indication of the Data Group Length.216.3Different methods of transferring MOT objects.236.3.1Repetition on object level.246.3.2Insertion of additional header information.246.3.3Interleaving objects in one MOT stream.256.3.4Repetition of Data Groups/segments.257Updating.257.1Object update.257.2Updating header information/triggering objects.267.2.1Triggering an object.267.2.2Deletion of an object.268MOT directory.268.1Introduction.268.1AAssembly of MOT objects and MOT directory.278.2MOT directory coding.278.2.1Parameters of the DirectoryExtension.288.2.2SegmentSize of the MOT directory.288.2.3Identification of the MOT directory.298.3Use of the MOT directory.298.3.1Segment reception order.298.3.2Service acquisition.298.3.3Version control.308.3.4Allocation of TransportIds.30SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)48.3.5Prioritizing objects within the carousel.308.3.6Managing updates to the carousel.308.3.7Cache management.30History.31SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)5Intellectual Property RightsIPRs essential or potentially essential to the present document may have been declared to ETSI. The informationpertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be foundin SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respectof ETSI standards", which is available free of charge from the ETSI Secretariat. Latest updates are available on theETSI Web server (http://www.etsi.org/ipr).Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guaranteecan be given as to the existence of other IPRs not referenced in SR 000 314 (or the updates on the ETSI Web server)which are, or may be, or may become, essential to the present document.ForewordThis European Standard (Telecommunications series) has been produced by the Joint Technical Committee (JTC)Broadcast of the European Broadcasting Union (EBU), Comité Européen de Normalisation ELECtrotechnique(CENELEC) and the European Telecommunications Standards Institute (ETSI).NOTE 1:The EBU/ETSI JTC Broadcast was established in 1990 to co-ordinate the drafting of standards in thespecific field of broadcasting and related fields. Since 1995 the JTC Broadcast became a tripartite bodyby including in the Memorandum of Understanding also CENELEC, which is responsible for thestandardization of radio and television receivers. The EBU is a professional association of broadcastingorganizations whose work includes the co-ordination of its members' activities in the technical, legal,programme-making and programme-exchange domains. The EBU has active members in about 60countries in the European broadcasting area; its headquarters is in Geneva.European Broadcasting UnionCH-1218 GRAND SACONNEX (Geneva)SwitzerlandTel: +41 22 717 21 11Fax: +41 22 717 24 81The DAB system is a novel sound broadcasting system intended to supersede the existing analogue amplitude andfrequency modulation systems. It is a rugged, yet highly spectrum and power efficient sound and data broadcastingsystem. It has been designed for terrestrial and satellite as well as for hybrid and mixed delivery. The DAB system hasbeen publicly demonstrated on a number of occasions during its development. It has been subject to extensive field testsand computer simulations in Europe and elsewhere. In 1995, the European DAB forum (EuroDab) was established topursue the introduction of DAB services in a concerted manner world-wide, and it became the World DAB forum(World DAB) in 1997.NOTE 2:DAB is a registered trademark owned by one of the Eureka 147 partners.National transposition datesDate of adoption of this EN: 29 January 1999Date of latest announcement of this EN (doa): 30 April 1999Date of latest publication of new National Standardor endorsement of this EN (dop/e): 31 October 1999Date of withdrawal of any conflicting National Standard (dow): 31 October 1999SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)61ScopeThe present document specifies a transmission protocol, which allows to broadcast various kinds of data using theDigital Audio Broadcasting (DAB) system. It is tailored to the needs of Multimedia services and the specific constraintsgiven by the broadcasting characteristics of the DAB system. After reception this data can be processed and presented tothe user.The present document defines the transport specific encoding for data types not specified in ETS 300 401 [1] accordingto the transport mechanisms provided by DAB. It allows a flexible utilization of the data channels incorporated in theDAB system, as well as methods to manage and maintain a reliable transmission in a uni-directional broadcastenvironment. Provisions are also made for the creation and presentation of advanced Multimedia services using formatssuch as Hyper Text Markup Language (HTML) (see RFC 1866 [3]) or Multimedia and Hypermedia information codingExperts Group (MHEG) (see ISO/IEC CD 13522 [4]).The present document describes the core transport protocol. Subsequent parts or revisions of the present document willdescribe backwards compatible extensions.Aspects related to the further decoding and processing of the data objects carried are outside the scope of the presentdocument. Hardware or software implementation considerations are not covered.2ReferencesThe following documents contain provisions which, through reference in this text, constitute provisions of the presentdocument.· References are either specific (identified by date of publication, edition number, VersionNumber, etc.) ornon-specific.· For a specific reference, subsequent revisions do not apply.· For a non-specific reference, the latest version applies.· A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the samenumber.[1]ETS 300 401: "Radio broadcasting systems; Digital Audio Broadcasting (DAB) to mobile,portable and fixed receivers".[2]Sun Microsystems (1994, 1995): "The Java Language: A White Paper". Called "Java" in thepresent document.[3]RFC 1866 (November 1995): "Hyper Text Markup Language (HTML) Specification-2.0",T. Berners-Lee, D. Connolly; MIT/LCS onwards.[4]ISO/IEC CD 13522: "Information Technology; Coding of Multimedia and HypermediaInformation".[5]ISO DIS 10918: "Digital Compression and Coding of Continuous-tone Still Images", JointPhotographers Experts Group (JPEG).[6]ISO-8859-1 (1987): "International Standard; Information Processing; 8-bit Single-Byte CodedGraphic Character Sets; Part 1: Latin alphabet No. 1".[7]ISO-8859-2 (1987): "Information Processing; 8-bit single-byte coded graphic character sets;Part 2: Latin alphabet No. 2".[8]RFC 1521 (September 1993): "MIME (Multipurpose Internet Mail Extensions)Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies",N. Borenstein, N. Freed.SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)7[9]RFC 1945 (May 1996): "Hypertext Transfer Protocol – HTTP/1.0", T. Berners-Lee, R. Fielding,H. Nielsen.[10]ISO/IEC 646 (1991): "Information Technology; ISO 7-bit coded character set for informationinterchange".[11]© CompuServe, Incorporated (June 15, 1987): "GIF ™, Graphics Interchange Format ™:A standard defining a mechanism for the storage and transmission of raster-based graphicsinformation".[12]BMP: "Device-independent bitmap format used as default graphics file format for MicrosoftWindows".[13]ISO/IEC 11172-3 (1993): "Information technology; Coding of moving pictures and associatedaudio for digital storage media at up to about 1,5 Mbit/s; Part 3: Audio".[14]ISO/IEC 13818-3 (1994): "Generic coding of moving pictures and associated audio - Audio part".[15]ITU-T Recommendation G.711: "Pulse Code Modulation (PCM) of voice frequencies".[16]Apple Computer, Incorporated: "Audio Interchange File Format (AIFF): A Standard for SamplesSound Files".[17]Sony: "Adaptive Transform Acoustic Coding".[18]Sony: "Adaptive Transform Acoustic Coding II".[19]ISO/IEC 14496-3: "Very low bitrate audio-visual coding; Part 3: Audio".[20]ISO/IEC 11172-2 (1993): "Information technology; Coding of moving pictures and associatedaudio for digital storage media at up to about 1,5 Mbit/s; Part 2: Video".[21]ISO/IEC 13818-2 (November 1994): "Generic coding of moving pictures and associated audio -Video part". It is also standardized by ITU-T as Recommendation H.262.[22]ISO/IEC 14496-2: "Very Low Bitrate Audio-Visual Coding".[23]ITU-T Recommendation H.263: "Video coding for low bit rate communication".[24]ISO 7498 (1984): "Open Systems Interconnection (OSI) Basic Reference Model".[25]EN 50067: "Specification of the Radio Data System (RDS) for VHF/FM sound broadcasting in thefrequency range from 87,5 MHz to 108,0 MHz".SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)83Definitions and abbreviations3.1DefinitionsFor the purposes of the present document, the following definitions apply:body: The body carries any kind of data, where structure and content of the data are described in the header.byte ordering: All numeric values using more than one byte have to be coded in Big Endian Format (most significantbyte first). In all schematics the bits are ordered with the most significant bit of a byte ("b7") at the left end and leastsignificant bit ("b0") at the right end of the drawing.Conditional Access (CA): A mechanism by which user access to service components can be restricted.DAB receiver: The Multimedia Object Transfer (MOT) specific definition of a DAB receiver includes decoding of theDAB signal and resolving the multiplex structure of the main service channel.data carousel: A distinct set of objects that are used for cyclic transmission.data channels: The data channels in DAB (packet mode, X-PAD) provide the functionality on the transport layer inorder to convey the objects.data decoder: The data decoder processes the MOT data stream and applies both packet mode/X-PAD specificdecoding and then MOT decoding.ensemble: The transmitted signal, comprising a set of regularly and closely-spaced orthogonal carriers. The ensemble isthe entity which is received and processed. In general, it contains programme and data services.eXtended Programme Associated Data (X-PAD): The extended part of the PAD carried towards the end of the DABaudio frame, immediately before the scale factor Cyclic Redundancy Check (CRC). It is used to transport informationtogether with an audio stream which is related or synchronized to the X-PAD. No provisions for error detection areincluded in X-PAD so that additional protocols are required for some applications.Fast Information Channel (FIC): A part of the transmission frame, comprising the Fast Information Blocks (FIB),which contains the multiplex configuration information together with optional service information and data servicecomponents.header: The header consists of the header core and the header extension.header core: The header core contains information about the size and the content of the object, so that the receiver candetermine whether it has system resources to decode and present the object or not.header extension: The header extension includes additional information about the body.Main Service Channel (MSC): A channel which occupies the major part of the transmission frame and which carriesall the digital audio service components, together with possible supporting and additional data service components.MOT data service: A data service comprises information which is intended to be presented to a user, i.e. text, pictures,video or audio sequences. An application decoder is required to gain access to the data. This might be a viewer whichdecodes text and pictures and displays them on a screen. It might also be a Multimedia engine which manages variousinputs and outputs a number of different audio-visual media synchronously. In terms of MOT a data services consists ofone or an ordered collection of several objects. It is not in the scope of MOT to deal with the content of the object, butto carry information to support both presentation and handling of these objects.MOT directory: Within a data carousel the MOT directory contains a complete description of the content of thecarousel.MOT object: A MOT object is used to transfer data in DAB, the object contains a header and a body carrying thepayload.MOT stream: One stream of MOT objects is transferred in an individual service component (packet mode) or as part ofthe X-PAD of a programme service, where several MOT objects might be conveyed in parallel by interleaving.SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)9packet mode: The mode of data transmission in which data are carried in addressable blocks called packets. Packets areused to convey MSC Data Groups within a sub-channel. The packet mode carries the load in packets of a certain size,separating different streams of packets by specific addresses. Error detection and repetition are already covered bypacket mode and thus allow a reliable and flexible data transmission.Programme Associated Data (PAD): Information which is related to the audio data in terms of content andsynchronization. The PAD field is located at the end of the DAB audio frame.service: The user-selectable output which can be either a programme service or a data service.service component: A part of a service which carries either audio (including PAD) or data. The service components ofa given service are linked together by the Multiplex Configuration Information (MCI). Each service component iscarried either in a sub-channel or in the Fast Information Data Channel (FIDC).service label: Alphanumeric characters associated with a particular service and intended for display in a receiver.TransportId: This 16-bit field shall uniquely identify one data object (file and header information) from a stream ofsuch objects. It shall be used to indicate the object to which the information carried in the segment belongs or relates. Itis valid only during the transport time of the object.transport time: The transport time is the entire duration which is needed to transfer a MOT object completely(including all repetitions), i.e. the time during which a particular TransportId is valid for one MOT object.X-PAD Data Group: A package of data for carrying one segment of an MOT object in the Extended ProgrammeAssociated Data (X-PAD).3.2AbbreviationsFor the purposes of the present document, the following abbreviations apply:AIFFAudio Interchange File FormatASCIIAmerican Standard Code for Information InterchangeATRACAdaptive Transform Acoustic CodingBMPWindows BitmapCAConditional AccessCRCCyclic Redundancy CheckDABDigital Audio BroadcastingECMEntitlement Checking MessageEMMEntitlement Management MessageETSEuropean Telecommunication StandardFFTFast Fourier TransformFIBFast Information BlockFICFast Information ChannelFIDCFast Information Data ChannelGIFGraphics Interchange FormatHFHigh FrequencyHTMLHyper Text Markup LanguageHTTPHyper Text Transfer ProtocolJFIFJPEG File Interchange FormatJPEGJoint Photographic Experts GroupMCIMultiplex Configuration InformationMHEGMultimedia and Hypermedia information coding Experts GroupMIMEMultipurpose Internet Mail ExtensionsMJDModified Julian DateMOTMultimedia Object TransferMPEGMoving Pictures Expert GroupMSCMain Service ChannelPADProgramme Associated DataPCMPulse Code ModulationPLIParameter Length IndicatorRfaReserved for future additionSIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)10RfuReserved for future useUTCUniversal Time Co-ordinatedX-PADExtended Programme Associated Data4General description of the MOT protocol4.1Requirements of Multimedia servicesMultimedia in general can be referred to as information and its presentation in various formats (visible, audible, etc.)and forms (text, pictures, video, etc.). The material is often structured and packaged into a number of containers or fileswhich shall be either completely available before the presentation or are delivered on request of the user.Multimedia services require to control the presentation (e.g. the arrangement of visible information on a screen) andtherefore direct access to both hardware and software resources of the receiver/terminal is essential. The appropriatetime shall also be considered for the presentation. Thus it is required to synchronize the various elements (e.g. videotogether with the sound), i.e. some kind of a runtime environment is necessary.4.2Problems MOT is attempting to solveThe MOT protocol is a data transport protocol specified to provide facilities for the transportation of Multimedia objectsin the DAB system. These objects can consist of:-self-contained Multimedia objects, such as:-MHEG (see ISO/IEC CD 13522 [4]); and-Java [2]; or-actual files containing for example:-JPEG pictures (see ISO DIS 10918 [5]);-American Standard Code for Information Interchange (ASCII) text;-Moving Pictures Expert Group (MPEG) video or audio sequences.For transmission of Multimedia objects, the protocol provides the means to use the following data channels of the DABsystem:-PAD; and-Packet Mode.Session layerTransport layerPacket Mode/X-PADNetwork layerPackets/X-PAD data subfieldsFigure 1: Target for the MOT protocolMOT interconnects the closed and well defined world of DAB to the open world of Multimedia services with its largevariety of systems and data formats. It comprises functionality to carry information to the terminal, respectively the user.MOT does not cover issues specific to runtime environments to control Multimedia services, i.e. the interpretation andexecution of object code, pseudo code or script languages. This shall be included in the particular application.SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)114.3Receiver architecture reference modelAn example decoding process for MOT objects is shown in figure 2 (data flow top-down).HF PartFFT, Demux, Channel DecoderPAD strippingPacket Mode DecoderPAD DecoderMOT DecoderApplicationDecoding processPresentationPacketXPAD subfieldData GroupData GroupObject dataAdditional informationspeakerMultimediaterminalAudio DecoderETS 300 401Figure 2: Example scheme for the data decoding part of a DAB receiverAdditional information: Additional information is carried in the MOT header. It is decoded by the MOT decoder andforwarded.Object data: Object data is carried in the MOT body.Parts within the grey background (HF part, FFT/demux/channel decoder, PAD stripping, PAD decoder, packet modedecoder and audio decoder) are defined in ETS 300 401 [1]).Interface to the MOT decoder: Communication between PAD/packet mode decoder and MOT decoder uses completeMain Service Channel (MSC) Data Groups (see ETS 300 401 [1]). The session header of a Data Group cannot beomitted, although it is optional in the DAB specification, since it carries the TransportId, which is necessary toreassemble the MOT objects.SIST EN 301 234:2000



ETSIEN 301 234 V1.2.1 (1999-02)125Object descriptionAn object consists of an ordered collection of the following three parts (see figure 3):Header core: The header core contains information about the size and the content of the object, so that the receiver candetermine whether it has system resources to decode and present the object or not.Header extension: The header extension includes information that supports the handling of the objects (e.g. memoryhandling) and provides additional information that can support an application.Body: The body carries any kind of data, where structure and content of the data is described in the header core and theheader extension.For transportation the object is split into several segments, at least one header segment and, if present, one bodysegment. Each segment is mapped into one Data Group as described in clause 6.The header is separated from the body during transportation in order to:-have the possibility to repeat the header several times before and during the transmission of the body (which isuseful when transmitting long objects);-send the header in advance in order to give the receiver the opportunity to "be prepared in advance" to the datathat is going to be received;-send the header unscrambled when the body is scrambled.7 bytesvariablevariableheader coreheader extensionbodyFigure 3: General object structureThe header shall be sent at least once preceding the body of the object.5.1Header coreThe header core shall be coded as shown in figure 4.28 bits13 bits6 bits9 bitsBodySizeHeaderSizeContentTypeContentSubTypeb55b28b27b15b14b9b8b0Figure 4: Structure of the header coreBodySize: This 28-bit field, coded as an unsigned binary number, indicates the total size of the body in bytes. TheBodySize all ones "FFFFFFF" (hexadecimal notation) indicates unknown size (at the beginning of the transmission).HeaderSize: This 13-bit field, coded as an unsigned binary number, indicates the total size of the header in bytes.ContentType: This 6-bit field indicates the main category of the body's content (see table 1)
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.