SMPTE ST 2038-2008 Carriage of Ancillary Data Packets in an MPEG-2 Transport Stream.pdf

1、 Copyright 2008 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved September 18, 2008 Table of Contents Page Foreword . 2 Intellectual Property 2 Introduction . 2 1 Scope . 3 2 Conformance Notation . 3 3 Normative References . 3

2、4 MPEG-2 Transport Stream Syntax 4 4.1 PMT Signaling 4 4.1.1 stream_type 4 4.1.2 anc_data_descriptor . 4 4.1.3 Registration Descriptor . 4 4.2 ANC Data PES Packet. 4 4.2.1 Semantics . 6 Annex A Bibliography (Informative) 7 Page 1 of 7 pages SMPTE 2038-2008SMPTE STANDARD Carriage of Ancillary Data Pa

3、ckets in an MPEG-2 Transport Stream SMPTE 2038-2008 Page 2 of 7 pages Foreword SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States of America, SMPTE has members in over

4、80 countries on six continents. SMPTEs Engineering Documents, including Standards, Recommended Practices and Engineering Guidelines, are prepared by SMPTEs Technology Committees. Participation in these Committees is open to all with a bona fide interest in their work. SMPTE cooperates closely with o

5、ther standards-developing organizations, including ISO, IEC and ITU. SMPTE Engineering Documents are drafted in accordance with the rules given in Part XIII of its Administrative practices. SMPTE Standard 2038 was prepared by Technology Committee D27. Intellectual Property At the time of publication

6、 no notice had been received by SMPTE claiming patent rights essential to the implementation of this Standard. However, attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. SMPTE shall not be held responsible for identifying any or all

7、 such patent rights. Introduction This section is entirely informative and does not form an integral part of this document. This document defines the carriage of ancillary (ANC) data within MPEG-2 Transport Streams. The mechanism provides a data pipe through which SMPTE 291M ANC data packets may be

8、conveyed transparently through equipment that uses the MPEG-2 Transport Stream protocol. The data need not be recognized or interpreted by said equipment. The lines used for the carriage of ANC data depend on the sample structure (e.g., SMPTE 274M for 1080 lines and SMPTE 296M for 720 lines). As a g

9、uideline for receiving equipment, the maximum possible amount of data payload to be re-embedded per line (or per field, as applicable) is 1920 samples * 10 bits (8 bit values are extended to 10 bits with parity and !parity) = 19,200 bits or less than 2.4kbytes. A mechanism is provided such that the

10、ANC data will be presented frame-accurately with the corresponding video. This mechanism is not intended for the carriage of audio, since there are already well-established mechanisms for doing that. This mechanism is not intended to carry EDH packets. SMPTE 2038-2008 Page 3 of 7 pages 1 Scope This

11、document defines the syntax and semantics for the carriage of SMPTE 291M Ancillary Data Packets in MPEG-2 Transport Stream PES packets. It supports ancillary data packets regardless of whether they originate from an SD or HD interface, or if the ANC data packet is from VANC or HANC, Y or C space. Su

12、fficient information is provided to enable the ANC packets at the output of the decoder to be restored to their “original” locations in the serial digital video signal. 2 Conformance Notation Normative text is text that describes elements of the design that are indispensable or contains the conforma

13、nce language keywords: “shall“, “should“, or “may“. Informative text is text that is potentially helpful to the user, but not indispensable, and can be removed, changed, or added editorially without affecting interoperability. Informative text does not contain any conformance keywords. All text in t

14、his document is, by default, normative, except: the Introduction, any section explicitly labeled as “Informative“ or individual paragraphs that start with “Note:” The keywords “shall“ and “shall not“ indicate requirements strictly to be followed in order to conform to the document and from which no

15、deviation is permitted. The keywords, “should“ and “should not“ indicate that, among several possibilities, one is recommended as particularly suitable, without mentioning or excluding others; or that a certain course of action is preferred but not necessarily required; or that (in the negative form

16、) a certain possibility or course of action is deprecated but not prohibited. The keywords “may“ and “need not“ indicate courses of action permissible within the limits of the document. The keyword “reserved” indicates a provision that is not defined at this time, shall not be used, and may be defin

17、ed in the future. The keyword “forbidden” indicates “reserved” and in addition indicates that the provision will never be defined in the future. A conformant implementation according to this document is one that includes all mandatory provisions (“shall“) and, if implemented, all recommended provisi

18、ons (“should“) as described. A conformant implementation need not implement optional provisions (“may“) and need not implement them as described. 3 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the ti

19、me of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below. SMPTE 291M-2006, Television Ancillary Data

20、 Packet and Space Formatting ITU-R BT.1700 (02/05), Characteristics of Composite Video Signals for Conventional Analogue Television Systems ITU-R BT.1120-6 (08/05), Digital Interfaces for HDTV Studio Signals ISO/IEC 13818-1:2007(E), Information Technology Generic Coding of Moving Pictures and Associ

21、ated Audio Information: Systems SMPTE 2038-2008 Page 4 of 7 pages 4 MPEG-2 Transport Stream Syntax 4.1 PMT Signaling The ANC data stream shall be identified in the PMT of the MPEG-2 Program of which it is part, using the following ISO/IEC 13818-1 syntax. 4.1.1 stream_type The stream_type shall be se

22、t to 0x06 (PES private data). 4.1.2 anc_data_descriptor The anc_data_descriptor, shown in Table 1, shall be used in the ES loop. The tag value shall be 0xC4 (user-defined in ATSC, DVB and SCTE). Table 1 anc_data_descriptor syntax Syntax No. of bits Mnem. Valid Range anc_data_descriptor() descriptor_

23、tag 8 uimsbf 0xC4 descriptor_length 8 uimsbf 0x00 0xFF for (I=0; iN; i+) descriptor() 4.1.2.1 Semantics descriptor(): This structure may be used to convey additional information about the ANC data component. The use is optional and currently undefined. Compliant receive devices shall ignore unrecogn

24、ized descriptors. 4.1.3 Registration Descriptor The anc_data_descriptor_tag is in ISO/IEC 13818-1 user private data code space. The anc_data_descriptor shall be preceded by an ISO/IEC 13818-1 registration_descriptor with format_identifier set to 0x56414E43 (“VANC“). 4.2 ANC Data PES Packet The forma

25、t of the ANC data PES packet is shown in Table 2. SMPTE 2038-2008 Page 5 of 7 pages Table 2 Format of the ANC Data PES packet Syntax No. of bits Identifier anc_data_packet() packet_start_code_prefix 24 0x000001 stream_id 8 0xBD private_stream_1 PES_packet_length 16 uimsbf 10 2 10 PES_scrambling_cont

26、rol 2 00 not scrambled PES_priority 1 bslbf data_alignment_indicator 1 1 payload aligned copyright 1 bslbf original_or_copy 1 bslbf PTS_DTS_flags 2 10 PTS present ESCR_flag 1 0 not present ES_rate_flag 1 0 not present DSM_trick_mode_flag 1 0 not present additional_copy_info_flag 1 0 not present PES_

27、CRC_flag 1 0 not present PES_extension_flag 1 0 not present PES_header_data_length 8 0x05 0010 4 0010 PTS3230 3 bslbf marker_bit 1 1 PTS2915 15 bslbf marker_bit 1 1 PTS140 15 bslbf marker_bit 1 1 for (i=0; iN; i+) 000000 6 000000 c_not_y_channel_flag 1 bslbf line_number 11 uimsbf horizontal_offset 1

28、2 uimsbf DID 10 bslbf SDID 10 bslbf data_count 10 bslbf for (j=0; jdata_count; j+) user_data_word 10 bslbf checksum_word 10 bslbf while (!bytealigned) 1 1 bslbf for (i=0 ;iN; i+) stuffing_byte 8 1111 1111 SMPTE 2038-2008 Page 6 of 7 pages Each ANC data PES packet shall contain ANC data from no more

29、than one line. ANC data packets extracted from the same line shall be conveyed in the same ANC data PES packet. The PTS value in the ANC data packet shall match the PTS value in the corresponding video PES packet within 2 ms. In the case of field pictures, PTS values for ANC data PES packets shall m

30、atch the PTS for field 1 of the frame with which the ANC data is associated. For 3:2 pull-down, the equivalent PTS values for field 1 shall be inferred if that field is not coded (due to repeat field-frame). The PTS values for ANC lines that belong to the same field shall be identical. 4.2.1 Semanti

31、cs Except as noted below, the definition of all syntax fields shall be as defined in ISO/IEC 13818-1 (shown as gray shaded fields in Table 2). In the case of fixed value assignment, the values shall be as defined in Table 2. c_not_y_channel_flag: For HD, this flag, when set to 1, indicates the ANC d

32、ata corresponds to the color difference channel. When set to 0, this flag indicates the ANC data corresponds to the luminance channel. For SD, this flag shall be set to 0. line_number: This field contains the line number (as defined in ITU-R BT.1700 SD or ITU-R BT.1120-6 HD) that corresponds to this

33、 ancillary data packet. The lines that are available to convey ancillary data are as defined in the applicable sample structure specification (e.g., SMPTE 274M, SMPTE 296M, ITU-R BT.656-4), and may be further restricted per SMPTE RP 168. horizontal_offset: This field defines the location of the ANC

34、packet relative to SAV. 0 means that the ADF sequence begins immediately following SAV. For HD, this is in units of Y samples (e.g., the range 0 to 2199 for 1080i 59.94). For SD, this is in units of (27MHz) multiplexed word numbers. DID, SDID, data_count, user_data_word, checksum_word: These fields

35、represent the data to be reinserted as ancillary data, per SMPTE 291M. For the purposes of the “for” loop syntax counter only, only the lower 8 bits of data_count, corresponding to bits b7 (MSB) through b0 (LSB) of the 10-bit SMPTE 291M data count word, shall be used. stuffing_byte: This is a fixed

36、8-bit value equal to 1111 1111 that may be inserted by a transmitting device. It may be ignored by the receiving device. SMPTE 2038-2008 Page 7 of 7 pages Annex A (Informative) Bibliography SMPTE 274M-2008, Television 1920 x 1080 Image Sample Structure, Digital Representation and Digital Timing Refe

37、rence Sequences for Multiple Picture Rates SMPTE 296M-2001, Television 1280 x 720 Progressive Image Sample Structure Analog and Digital Representation and Analog Interface SMPTE RP 168-2002, Definition of Vertical Interval Switching Point for Synchronous Video Switching ITU-R BT.656-5 (12/07), Interfaces for Digital Component Video Signals in 525-Line and 625-Line Television Systems Operating at the 4:2:2 Level of Recommendation ITU-R BT.601