1、SMPTE STANDARD SMPTE 354M-2002 for Television - ATM Common Layer for Transport of Packetized Audio, video and Data over Asynchronous Transfer Mode using ATM Adaptation Layer Type 1 1 Scope This standard defines a common layer for transport of packetized audio, video, and data over asynchronous trans
2、fer mode (ATM) using ATM adaptation layer iype 1 (AALl). This standard covers the transmission of the packetized audio, video, and data including rates at standard time and faster-than-real time, and multipro- gram transmission as well. The common layer shall be a higher layer located immediately ab
3、ove the AAL1 layer, and which does not depend on any application. The usage of the transmission packets for particular applications is defined in other documents. Page 1 of 1 O pages 3 Common layer The common layer is the next higher layer located immediately above AALl and transports packets of app
4、lications. The common layer consists of two sublayers. The lower sublayer is the SYNC layer and the higher sublayer is the container layer. 3.1 SYNC layer The SYNC layer defines the SYNC stream block (SSB) which includes containers, but does not define the usage of such containers. The container is
5、defined as follows for transmitting packetized audio, video, and data. 2 Normative references 3.1.1 SYNC stream block (SSB) format The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indica
6、ted were valid. The standard is subject to revision, and patties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below. ANSVSMPTE 298M-1997, Television - Universal Labels for Unique Identification of Di
7、gital Data SMPTE 336M-2001, Television - Data Encoding Protocol using Key-Length-Value ISO/IEC 8825-1 :1998 (ITU-T X.690), Information Technology - ASN.l Encoding Rules - Specifica- tion of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER), Pars. 8.1.3
8、.4 and 8.1.3.5 ITU-T 1.363.1 (08/96), 6-ISDN ATM Adaptation Layer Specification: Type 1 AAL The SSB data are mapped to AAL1 byte by byte. SSB is transmitted sequentially from the first byte of the SSB header during the time interval of a single video frame. SSB consists of SSB header and one or more
9、 containers. The SSB format is shown in figure 1 and shall include the following: UL key: 16 bytes - UL header: 2 bytes - UL designators: 6 bytes - Item designator: 8 bytes SSB value length: Variable (defined in 3.1.3) SSB value: Variable - Reserved: 4bytes - Number of containers: 1 byte - Number of
10、 programs: 1 byte - Container information blocks: 9 bytes - Containers: The length of each container is indicated in each container infor- mation block. Copyright O 2002 by THE SOCIW OF MOTION PICTURE AND TELEVISION ENGINEERS 595 W. Harisdale Ave., White Plains, NY 10607 (914) 761-1 100 Approved Jan
11、uary 31,2002 SMPTE 354M-2002 4 4 b4 SYNC Stream Block (SSB) b b b SSB Header Containers 4 SSB Value sbytas,i byteE,l byt therefore, the 3.1.4.3 Number of programs The number of programs shall consist of 1 byte. It indicates the number of programs within the SSB. Page 2 of 1 O pages SMPTE 354M-2002 3
12、.1.4.4 Container information block The container information block shall consist of 9 bytes. The number of container information blocks is the same number as the number of containers (n) within the SSB. Each container information block is assigned a number from O to (n - l), indicating to which cont
13、ainer in the container sequence within the SSB the information belongs. The first container informa- tion block is assigned O. Each container information block consists of the program number, the container size, and the container offset. The container informa- tion block mapping is shown in figure 2
14、 9 bytes j Container Infohation ! Figure 2 - Container information 3.1.4.4.1 Program number The program number shall consist of 1 byte. It indi- cates the program number of the container data within the SSB. It is assigned sequentially from O to total program number - 1. 3.1.4.4.2 Container size The
15、 container size shall consist of 4 bytes. It indicates the size of the container in bytes. 3.1.4.4.3 Container offset The container offset shall consist of 4 bytes. It indi- cates the header byte position of the container from the start byte of the SYNC stream block. 3.1.4.5 Container The container
16、is designed for transporting packetized data. The length of the container is indicated by con- tainer information described in 3.1.4.4. The container does not contain its SSB sequence number, but it is assigned a different 4-byte sequence number as an identifier. 3.2 Container layer The container la
17、yer defines the structure of the con- tainer in SSB. Each container is intended to hold a video frame (optionally two fields) worth of packetized audio, video, and data. 3.2.1 Container format The container has two basic modes: simple mode and extended header mode. The simple mode supports four obje
18、cts of somewhat restricted types. The ex- tended header mode, needed when there are more than four objects, supports up to 16 objects. The container format is shown in figure 3. The container with m objects shall include the following: Container header: 88 bytes Extended container header (if needed)
19、: (m-4)*4 bytes (m = 4) Object: The length is indicated in the container header or extended container header. 3.2.1.1 Container header The container header shall consist of 88 bytes and each word consists of 4 bytes. The first 6 words of the header apply to the entire container. The remaining 16 wor
20、ds are divided into four identically structured sections, one for each data object. The container header shall include the following and is shown in figure 4: Sequence number: 4 bytes Clip ID: 4 bytes Container time stamp: 8 bytes Video frame rate: 1 byte Transmission rate: 1 byte Reserved: 2 bytes
21、Mode: 1 byte Number of objects: 1 byte Reserved: 1 byte Size of extended header: 1 byte Object O information: 4 words (16 bytes) Object 1 information: 4 words (16 bytes) Object 2 information: 4 words (16 bytes) Object 3 information: 4 words (16 bytes) (Each object information has class, size, offset
22、, and object type defined.) Page 3 of 10 pages SMPTE 354M-2002 Container Object0 Header :Object m-i! . Object 1 Object2 Object3 Object4 i Object5 Figure 3 - Container format Word I Identifier BYTE O BYTE 1 BYTE 2 BYTE 3 O I Seauence number MSB Figure 4 - Container header -number- -number- LS B Page
23、4 of 10 pages 20 21 Object 3 offset MSB -offset- -offset- LSB Object 3 Object type Object type Object type Object type Object type defined defined defined defined defined SMPTE 354M-2002 3.2.1.1.1 Sequence number A 32-bit unsigned integer used to identify where, in a series of containers representin
24、g a video clip, this objects fits. 3.2.1.1.2 Clip ID A 32-bit unsigned integer used for identification of a video clip. Intended for use by a higher level protocol as a way to identify the container as an element of a specific video clip. 3.2.1.1.3 Container time stamp A 64-bit word used to store a
25、time stamp for trans- mission purposes. This tirne stamp represents the container time. There may be other time stamps and time codes associated with each object. The time stamp format is described as the ANSI X3.230 (FC-PH) expiration time which is a b) Negotiated - for use by a higher level protoc
26、ol to dynamically assign data types; c) Vendor specific - for open use and guaranteed not to be assigned in the future. This standard makes no guarantee of interoperability when using vendor specific types of indices. The informative object table hierarchy is shown in figure 6. Object Type 10 Table
27、Index I ( ,I Y OOh Null , Exxxh Negotiated Fxxxh Vendor specific . , , , Fxh Vendor specific . , , . , . Object Type 40 Table Index 0000h Null 0001h AES/EBU2ch 1 nnnnh-DFFFh Reserved WI .*i Fxxxh Vendor specific I Figure 6 - Object table hierarchy Page 7 of 10 pages SMPTE 3541111-2002 Null object 3.
28、2.1.3.1 Object type bytes Object type bytes are unsigned bytes. The value represents a table. The values assigned are listed in indicated by the object type bye of the same object class word. For the case of a null object, the bytes are setto0000h. ooh table 2. Values listed as reserved areforfuture
29、assign- ment by ANSI. Values labeled vendor specific are intended for proprietary use by a specific vendor and will not be reassigned in the future. Note that in each table pointed to by the type byte, there are also vendor specific values. The intent is to allow a vendor to use an assigned type cla
30、ssification (such as uncom- pressed video) with a proprietary format. Therefore, vendor specific type bytes should only be used for types not listed in table 2. Undefined object type byte numbers are reserved. Video. UnCOmDreSSed Table 2 - Object class type 1 Oh Type I Code Video, compressed 11h Vid
31、eo program Reserved for video program Graphics (multiplexed stream) Audio, uncomprecsed Au di o, co mp recsed Rece rve d Ancillary data 20h 21h to 2Fh 3Xh 41 h 42h 60hto DFh 5Xh Negotiated object types I EOhto EFh Vendor specific I FOhto FFh SSB Header 3.2.1.3.2 Object index bytes Container O Contai
32、ner 1 Container 2 . (Frame f) (Frame ftl) (Frame ft2) (Frame ftn-i) The object index bytes are defined to be a 2-byte unsigned value representing an index to the table 4 Transmission order 4.1 Faster-than-real-time transmission In the case of faster-than-real-time transmission (n times transmission)
33、, n pieces of container are used within a single SSB. One video frame worth of video, audio, and ancillary data is mapped into one container in time sequence. N pieces of container are transmit- ted continuously. An example is shown in figure 7. 4.2 Multiprogram transmission In the case of multiprog
34、ram transmission, one video frame worth of video, audio, and ancillary data is mapped into one container and all programs are multiplexed into SSB. The program number shall be indicated by program number in the container infor- mation. The order of the program is the same within every SSB. An exampl
35、e is shown in figure 8 (p pro- gram transmission). 4.3 Combination of faster-than-real-time trans- mission and multiprogram transmission In the case of a combination of faster-than-real-time transmission and multiprogram transmission, all pro- grams are multiplexed into SSB. The program number shall
36、 be indicated by program number in the container information. Plural containers of faster-than-real-time programs are transmitted continuousiy and the order of the program is the same within every SSB. An example in the case of the 3-program transmission (program O: 1 time; program 1 : 4 times; prog
37、ram 2: 1 time) is shown in figure 9. Transmission order, Figure 7 - Faster-than-real-time transmission Page 8 of 10 pages SMPTE 354M-2002 SSB Header Container O Container 1 Container 2 . (Program O) (Program 1) (Program 2) - Figure 8 - Multiprogram transmission Transmission order, Figure 9 - Combina
38、tion of faster-than-real-time transmission and multiprogram transmission Annex A (informative) SSB sequence As described in 3.1.2.3, item designator-O and item desig- nator-1 are used alternately in the SSB sequence. The overview of the SSB sequence is shown in figure A.1. Transmission order b SSB (
39、n-i) SSB (n) SSB (n+i) SSB (n+2) SSB (n+3) - y1 FI yxrIFly1 - SSB Hude SSB Hadcr SSB Hader SSB Hada SSB HwJa Ian Designator-i) (Item D6ignator-O) gam Designator-I) (Item Dfsignamr-O) (rm DaignaMior-I) Figure A.l- SSB sequence Page 9 of 10 pages SMPTE 354M-2002 Annex B (informative) Bibliography ANSI
40、 X3.230-1994 (R1999), Information Technology - Fibre Channel - Physical and Signaling Interface (FC-PH) ANSIISMPTE 125M-1995, Television - Component Video Signal 4:2:2 - Bit-Parallel Digital Interface ANSIISMPTE 259M-1997, Television - 10-Bit 4:2:2 Com- ponent and 4fsc Composite Digital Signals - Se
41、rial Digital Interface ANSIISMPTE 267M-1995, Television - Bit-Parallel Digital Interface - Component Video Signal 4:2:2 16x9 Aspect Ratio ANSIISMPTE 293M-1996, Television - 720 x 483 Active Line at 59.94-Hz Progressive Scan Production - Digital Representation ANSIISMPTE 294M-1997, Television - 720 x
42、 483 Active Line at 59.94-Hz Progressive Scan Production - Bit-Serial Interfaces ANSIISMPTE 296M-1997, Television - 1280 x 720 Scan- ning, Analog and Digital Representation and Analog Inter- face SMPTE 274M-1998, Television - 1920 x 1080 Scanning and Analog and Parallel Digital Interfaces for Multip
43、le Picture Rates SMPTE 292M-1998, Television - Bit-Serial Digital Interface for High-Definition Television Systems ISOIIEC 8824-1:1998 (ITU-T X.680), Information Technology -Abstract Syntax Notation One (ASN.l) - Specification of Basic Notation ITU-T 1.356 (03/00), 8-ISDN ATM Layer Cell Transfer Per- formance ITU-T 1.361 (02/99), B-ISDN ATM Layer Specification Page 1 O of 10 pages
