1、 Table of contents 1 Scope 2 Normative references 3 Glossary of acronyms, terms and data types 4 Introduction 5 Type D-10 mapping 6 Application issues Annex A Descriptor set values for the essence elements defined in this standard Annex B Bibliography 1 Scope This standard defines the mapping of com
2、pressed picture data according to the type D-10 data stream and up to 8 channels of AES3 data into the material exchange format generic container (MXF-GC). This mapping is given the acronym: MXF-GC(D-10). The MXF specification is written in several parts. This is one of a set of documents that defin
3、e the contents of the MXF file body. The MXF file format specification includes operation pattern specifications that may define restrictions to be placed on the way in which this essence container type can be implemented. The reader is advised to carefully study the appropriate operational pattern
4、document for compliance to the defined implementation. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision
5、 and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. SMPTE 331M-2004, Television Element and Metadata Definitions for SDTI-CP SMPTE 356M-2001, Television Type D-10 Stream Specifications:
6、 MPEG-2 4:2:2PML for 525/60 and 625/50 SMPTE 377M-2004, Television Material Exchange Format (MXF) File Format Specification Page 1 of 12 pages SMPTE 386M-2004 Copyright 2004 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 595 W. Hartsdale Ave., White Plains, NY 10607 (914) 761-1100 Approve
7、d September 22, 2004 SMPTE STANDARD for Television Material Exchange Format (MXF) Mapping Type D-10 Essence Data to the MXF Generic Container SMPTE 386M-2004 Page 2 of 12 pages SMPTE 379M-2004, Television MXF Generic Container SMPTE 385M-2004, Television Mapping SDTI-CP Essence and Metadata into the
8、 MXF Generic Container SMPTE RP 204-2000, SDTI-CP MPEG Decoder Templates 3 Glossary of acronyms, terms and data types The general glossary of acronyms, terms and data types used in the MXF specification is given in SMPTE 377M. Supplementary glossaries of acronyms and terms are defined in SMPTE 379M
9、and SMPTE 385M. They are not repeated here to avoid any divergence of meaning. 4 Introduction The MXF generic container (MXF-GC) is a streamable essence container that encapsulates a sequence of one or more content packages (CP). SMPTE 379M defines the MXF generic container as the native essence con
10、tainer in MXF files. SMPTE 385M defines a system item that is compatible with SMPTE 326M (SDTI-CP) and also defines how SDTI-CP essence and metadata can be used in the MXF generic container. This standard specifies the mapping of the type D-10 stream data and 8-channel AES3 data into the MXF generic
11、 container. This same data is directly compatible with SDTI-CP constrained by the template defined in SMPTE RP 204. 5 Type D-10 mapping The MPEG-2 baseline decoder template specified by SMPTE RP204 provides for codecs operating with MPEG-2 4:2:2PML encoded pictures accompanied by an 8-channel AES3 d
12、ata capability and a general data element. It specifies a codec capable of basic timing and transfer modes for SDTI operation. The specification is a baseline allowing receiver/decoders to be designed with higher capabilities if and when desired. Details of the element and metadata definitions plus
13、the MPEG-2 baseline SDTI decoder template are given in SMPTE 331M and SMPTE RP 204. This specification shall use frame-based mapping as defined by SMPTE 379M. The order of items in this mapping shall be system, picture, sound and data (if present). NOTE Auxiliary items and elements in SMPTE 326M are
14、 synonymous with data items and elements in the MXF generic container. 5.1 System item mapping The mapping of system item data shall comply with that defined in SMPTE 385M. The system metadata pack and the package metadata set are required. The presence of the picture item, sound item, data item and
15、 control element depends on the setting of the system metadata bitmap as defined in SMPTE 385M. The universal label (UL) used in the MXF GC(D-10) system item and in the MXF header metadata shall have the following value: SMPTE 386M-2004 Page 3 of 12 pages Table 1 Specification of the MXF-GC(D-10) es
16、sence container UL Byte No. Description Value (hex) Meaning 113 See SMPTE 379M - Defined in Table 3 of SMPTE 379M 14 Type D-10 Mapping 01h Mapping compliant to SMPTE 356M and SMPTE RP204 15 MPEG Constraints: SMPTE 356M 01h 02h 03h 04h 05h 06h 50 Mbps, 625/50 50 Mbps, 525/60 40 Mbps, 625/50 40 Mbps,
17、525/60 30 Mbps, 625/50 30 Mbps, 525/60 16 Type: Template Extension 01h or 02h 01h = template defined in this document 02h = extended template This label value as described above shall be used as the essence container UL in the preface set and the appropriate file descriptor set of the header metadat
18、a and in the partition pack. 5.2 Picture item mapping There shall be one essence element in the MXF-GC picture item which shall be a MPEG-2 4:2:2PML video elementary stream constrained according to SMPTE 356M. 5.2.1 Essence element key The essence element key value shall be defined as follows: Table
19、 2 Key value for the type D-10 picture element Byte No. Description Value (hex) Meaning 112 See SMPTE 379M - Defined in Table 2 of SMPTE 379M 13 Item Type Identifier 05h SDTI-CP compatible picture item 14 Essence Element Count 01h One essence element present 15 Essence Element Type 01h MPEG2 422PML
20、element as defined in SMPTE 331M 16 Essence Element Number nnh As defined by SMPTE 379M section 7.1. 5.2.2 Essence element length The length field of the KLV coded element shall be 4 bytes BER long-form encoded (i.e., 83h.xx.yy.zz). The value of the length field shall correctly define the length of
21、the element value. 5.2.3 Essence element value The MPEG-2 4:2:2PML video elementary stream is as per the definition in SMPTE 331M. The encoded bitstream is constrained according to the type D-10 MPEG-2 data stream specification (SMPTE 356M). SMPTE 386M-2004 Page 4 of 12 pages NOTE As per SMPTE 356M,
22、 the maximum bit-rate for this stream is 50 Mbps. When operating at 50 Mbps, the size (in bytes) is: For 525/60 operation: 208,541 bytes; For 625/50 operation: 250,000 bytes. 5.3 Sound item mapping There shall be one sound element in the MXF GC sound item which shall be an 8-channel AES3 element def
23、ined according to SMPTE 331M. 5.3.1 Essence element key The essence element key value shall be as follows: Table 3 Key value for the 8-channel AES3 sound element Byte No. Description Value (hex) Meaning 112 See SMPTE 379M - Defined in Table 2 of SMPTE 379M 13 Item Type Identifier 06h SDTI-CP compati
24、ble sound Item 14 Essence Element Count 01h One essence element present 15 Essence Element Type 10h 8-channel AES3 element as defined in SMPTE 331M 16 Essence Element Number nnh As defined by SMPTE 379M section 7.1. 5.3.2 Essence element length The length field of the KLV coded element shall be 4 by
25、tes BER long-form encoded (i.e., 83h.xx.yy.zz). The value of the length field shall correctly define the length of the element value. 5.3.3 Essence element value The 8-channel AES3 element is as per the definition in SMPTE 331M. Active channels are filled with AES3 data according to the stream valid
26、 flag defined in SMPTE 331M. The active data length varies according to 625/50 or 525/60 operation (and in 525/60 operation varies over the frame sequence as it has a 5-frame sequence). 5.4 Data item mapping The data item may contain zero or more data elements as defined in SMPTE 331M. If the data i
27、tem has a variable length in each content package, then the end of the data item should be padded with the KLV fill item to ensure that the content package size is constant. NOTE The KLV fill item ensures that a simple index table can be used. 5.4.1 Essence element key The essence element key value
28、shall be as follows: SMPTE 386M-2004 Page 5 of 12 pages Table 4 Key value for an auxiliary data element Byte No. Description Value (hex) Meaning 112 See SMPTE 379M Defined in Table 2 of SMPTE 379M 13 Item Type Identifier 07h SDTI-CP compatible data item 14 Essence Element Count nnh One or more essen
29、ce elements present 15 Essence Element Type Per SMPTE 331M Data essence element as defined in SMPTE 331M 16 Essence Element Number xxh As defined by SMPTE 379M section 7.1. 5.4.2 Essence element length The length field of the KLV coded element shall be 4 bytes BER long-form encoded (i.e., 83h.xx.yy.
30、zz). The value of the length field shall correctly define the length of the element value. 5.4.3 Essence element value As defined by SMPTE 331M. 6 Application Issues 6.1 Application of the KLV fill item Within any MXF partition containing an essence container with this mapping specification, the KAG
31、 value defined in the partition pack shall have the value of 512 (02.00h) and the first byte of the key of the first element of each Item shall be aligned to the KLV alignment grid of that partition. For each Item in a content package, the length of the KLV fill item should be the minimum required t
32、o align to a KAG boundary and be consistent with maintaining a constant content package size. Where possible, any immediately preceding partition should align the start of each MXF partition containing an essence container with this mapping specification to a byte offset that is an integer multiple
33、of the defined KLV alignment grid relative to the start of the header partition pack. The length field of the KLV fill item shall be 4 bytes, BER long-form encoded (i.e., 83h.xxh.yyh.zzh). NOTE The application of the KAG shall comply with SMPTE 377M, section 5.4.1. 6.2 Application of index tables fo
34、r constant GC item sizes One index table segment should be present in the MXF header partition. Repetition of this index table segment in subsequent partitions is optional. The definition of the index table format is given in the MXF file format specification (SMPTE 377M). This section describes the
35、 application of index tables to an MXF-GC(D-10) essence container. Any KLV fill items are treated as a part of the element that they follow and are not indexed in their own right. Note that the index entry array is not used for GC(D-10) types with fixed item lengths. Note also that an “edit unit” is
36、 the duration of one content package (i.e., video frame). SMPTE 386M-2004 Page 6 of 12 pages The index table segment is constructed as follows: Table 5 Index table segment set Item Name Meaning Value Index Table Segment A segment of an Index Table Length Set Length Instance ID Unique ID of this inst
37、ance Index Edit Rate Frame rate of the Type D-10 video 25,1 or 30000, 1001 Index Start Position Byte address of first edit unit indexed by this table segment 0 Index Duration Number of edit units indexed by this table segment (NSA) 0 Edit Unit Byte Count Defines the length of a fixed size edit unit
38、0 IndexSID Identifier of the index table segment BodySID Identifier of the essence container Slice Count Number of slices minus 1 (NSL) 0 Delta Entry Array Map of elements in each content package (optional) (see table 6) IndexEntry Array Index from sample number to stream offset Not encoded This map
39、ping specification may use the optional delta entry array table as defined in SMPTE 377M. An example delta entry array table for system, picture, sound and data elements is given below: SMPTE 386M-2004 Page 7 of 12 pages Table 6 Structure of example delta entry array Field Name Meaning Typical Value
40、s Comment NDE Number of delta entries 4 Length Length of each delta entry 6 PosTableIndex No temporal reordering 0 Slice Slice number in index entry 0 Element Delta (Fixed) Delta from start of slice to this element 0 Element 0 e.g. System Data Pack Element PosTableIndex No temporal reordering 0 Slic
41、e Slice number in index entry 0 Element Delta (Fixed) Delta from start of slice to this element Len(system item + fill) Element 1 e.g. picture item PosTableIndex No temporal reordering 0 Slice Slice number in index entry 0 Element Delta (Fixed) Delta from start of slice to this element Len(system it
42、em + fill + element 1 + fill) Element 2 e.g. sound item PosTableIndex No temporal reordering 0 Slice Slice number in index entry 0 Element Delta (Fixed) Delta from start of slice to this element Len(system item + fill + element 1 + element 2 + fill) Element 3 e.g. data item 6.3 File descriptor sets
43、The file descriptor sets are those structural metadata sets in the header metadata that describe the essence and metadata elements defined in this standard. The structure of these sets is defined in the MXF file format specification (SMPTE 377M). The definition of the property values in the file des
44、criptor sets appropriate to this specification are given in annex A of this standard. File descriptor sets should be present in the header metadata for each essence element and for the system metadata pack element. 6.4 Mapping track numbers to generic container elements The number of essence tracks
45、in the associated header metadata package shall be the same as the number of essence elements used in this mapping application. The track number value shall be derived as described in the MXF generic container specification (SMPTE 379M). The associated header metadata package should define one metad
46、ata track to describe the contents of the system metadata pack of the CP-compatible system item. The track number value shall be derived as described in SMPTE 385M. This track can be used to describe the date/time components in the CP-compatible system item. SMPTE 386M-2004 Page 8 of 12 pages 6.5 Es
47、sence container partitions The type D-10 mapping maintains each content package of the generic container as a separate editable unit with the contents of the system, picture, sound and data items in synchronism. As a consequence, if the essence container using this mapping is partitioned, then each
48、partition shall contain an integer number of content packages where each content package contains all the Items required. SMPTE 386M-2004 Page 9 of 12 pages Annex A (informative) Descriptor set values for the essence elements defined in this standard The file descriptors in this annex are defined in
49、 SMPTE 377M. These descriptors are replicated here with the aim to indicate property values, where appropriate. Where more than one file descriptor is referenced by a package, it will need to first reference the multiple descriptor as described in SMPTE 377M. In all tables describing sets in this annex, the columns are defined as follows: Item name: the name of the property; Type: the defined type of the property; Len: the length of the value in bytes where known; Meaning: a description of the property; 525/60: default valu
