SMPTE ST 2047-2-2010 Carriage of VC-2 Compressed Video over HD-SDI.pdf

1、 Copyright 2010 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved January 12. 2010 SMPTE ST 2047-2:2010 SMPTE STANDARD Carriage of VC-2 Compressed Video over HD-SDI Page 1 of 11 pages Table of Contents Page Foreword . 2 Intellec

2、tual Property 2 Introduction 2 1 Scope . 3 2 Conformance Notation . 3 3 Normative References . 3 4 General Description . 4 4.1 Source Image Formats 4 4.2 Timing Reference Codes . 4 4.3 Ancillary Data 4 4.4 Audio Data . 4 4.5 Time Code . 4 4.6 Video Payload Identifier 4 4.7 Viewable Content (Informat

3、ive) 6 5 VC-2 Mezzanine Bit-Stream Mapping 6 6 Interface Data Format 6 6.1 Compressed Data Mapping . 6 6.2 Viewable Picture 7 6.3 Creating a Viewable Picture 7 Annex A Effect of Halftone Dither (Informative) . 9 Annex B Characteristics of Compression Method (Informative) 10 Annex C Bibliography (Inf

4、ormative) . 11 SMPTE ST 2047-2:2010 Page 2 of 11 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 80 countries on

5、 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 other standards

6、-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 ST 2047-2 was prepared by Technology Committee 32NF. Intellectual Property At the time of publication no notice had be

7、en 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 such patent righ

8、ts. Introduction This section is entirely informative and does not form an integral part of this Engineering Document. The VC-2 compression standard defines a generic intra-frame compression system that can handle all defined video formats and more. A companion recommended practice defines constrain

9、ts on the VC-2 specification such that source video images of 1920 1080 pixels using 4:2:2 sampling at 50, 60, and 60/1.001 frames per second can be compressed by a ratio of approximately 5 to 2 resulting in a compressed bit-rate that can be carried over a single-link HD SDI operating at 1.5 Gb/s. T

10、his standard defines the provisions for mapping constrained VC-2 bit-streams onto the 1.5 Gb/s HD SDI link and describes a method by which additional bits are added to ensure that the resultant signal can be viewed on a HD SDI monitor, albeit in a somewhat noisy form. A key feature of this specifica

11、tion is that the transport of compressed data in this way is backward compatible with installed equipment. The compressed video is mapped entirely into active picture. The signal on the link therefore comprises a valid, viewable, video signal. This ensures compatibility with existing equipment such

12、routing and monitoring apparatus. An important feature of this mapping process is that it can be implemented in a practical form using currently available firmware and hardware, and, in the course of time, could be implemented within new chip designs to ensure the minimum impact on hardware power re

13、quirements and physical size. To aid readability, the serial digital bit rates are abbreviated throughout this document to 1.5 Gb/s in the cases of the bit rates 1.485 Gb/s (for 50 and 60 frames per second) and 1.485/1.001 Gb/s (for 60/1.001 frames per second), and to 3 Gb/s in the cases of the bit

14、rates 2.97 Gb/s (for 50 and 60 frames per second) and 2.97/1.001 Gb/s (for 60/1.001 frames per second). SMPTE ST 2047-2:2010 Page 3 of 11 pages 1 Scope This standard defines a means of mapping VC-2 data onto a single HD SDI link, based upon the SMPTE 292 data structure, to support the transport of 1

15、920 x 1080/50/P, 1920 x 1080/59.94/P (60/1.001), and 1920 x 1080/60/P systems with 4:2:2 YCBCRcolor encoding. As these systems require a raw uncompressed data capacity twice that of SMPTE 292, VC-2 mezzanine compression as defined by SMPTE RP 2047-1 is required to reduce the data rate. This link sup

16、ports the carriage of embedded audio, ancillary data and payload identification. A signal coded in accordance with this standard incorporates a noisy but recognizable picture that can be viewed using a standard SMPTE 292 video monitor. 2 Conformance Notation Normative text is text that describes ele

17、ments of the design that are indispensable or contains the conformance 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. Inform

18、ative text does not contain any conformance keywords. All text in this document is, by default, normative, except: the Introduction, any section explicitly labelled as “Informative“ or individual paragraphs that start with “Note:” The keywords “shall“ and “shall not“ indicate requirements strictly t

19、o be followed in order to conform to the document and from which no 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 p

20、referred but not necessarily required; or that (in the negative form) 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 t

21、hat is not defined at this time, shall not be used, and may be defined 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 mandato

22、ry provisions (“shall“) and, if implemented, all recommended provisions (“should“) as described. A conformant implementation need not implement optional provisions (“may“) and need not implement them as described. Unless otherwise specified the order of precedence of the types of normative informati

23、on in this document shall be as follows. Normative prose shall be the authoritative definition. Tables shall be next, followed by formal languages, then figures, and then any other language forms. 3 Normative References The following standards contain provisions which, through reference in this text

24、, constitute provisions of this standard. At the time 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 indicate

25、d below. SMPTE 12M-2-2008, Television Transmission of Time Code in the Ancillary Data Space SMPTE 274M-2008, 1920 x 1080 Image Sample Structure, Digital Representation and Digital Timing Reference Sequences for Multiple Picture Rates SMPTE 2047-2:2010 Page 4 of 11 pages SMPTE 291M-2006, Television A

26、ncillary Data Packet and Space Formatting SMPTE 292-2008, 1.5 Gb/s Signal/Data Serial Interface SMPTE 299-2009, 24-Bit Digital Audio Format for SMPTE 292 Bit-Serial Interface SMPTE 352M-2002, Television (Dynamic) Video Payload Identification for Digital Interfaces SMPTE ST 2042-1:2009, VC-2 Video Co

27、mpression SMPTE RP 2047-1:2009, VC-2 Mezzanine Level Compression of 1080P High Definition Video Sources 4 General Description 4.1 Source Image Formats The data for this interface shall be derived from the source image formats identified in Table 1. Table 1 Source image formats 4.2 Timing Reference C

28、odes Timing Reference codes shall be in conformance with those specified in SMPTE 274M and SMPTE 292 for the corresponding interlaced system (1920 x 1080/60/I, 1920 x 1080/59.94/I or 1920 x 1080/50/I). 4.3 Ancillary Data Ancillary data, if present, shall be mapped into the blanking area in conforman

29、ce with SMPTE 291M. 4.4 Audio Data Audio data, if present, shall be mapped into the ancillary data space in conformance with SMPTE 299. 4.5 Time Code Time code, if present, shall be mapped into the ancillary data space in conformance with SMPTE 12M-2. 4.6 Video Payload Identifier The payload identif

30、ier shall be present and shall be mapped into the ancillary data space in conformance with SMPTE 352M. The first byte of the payload identifier shall be used to identify the combination of video payload format and digital interface transport. For an interface in accordance with this standard Byte 1

31、shall be set to B0h. SMPTE 274 System No. System nomenclature Frame rate (Hz) Scanning format Signal format sampling structure/pixel depth 1 1920 1080/60/P 60 Progressive 4:2:2 (YCBCR) / 10-bit 2 1920 x 1080/59.94/P 60/1.001 Progressive 4:2:2 (YCBCR) / 10-bit 3 1920 x 1080/50/P 50 Progressive 4:2:2

32、(YCBCR) / 10-bit SMPTE ST 2047-2:2010 Page 5 of 11 pages Bytes 2 and 3 of the payload identifier shall be set in accordance with the picture rate, sampling structure, and aspect ratio etc of the viewable image being carried on the interface as shown in Table 2. Byte 4 of the payload identifier shall

33、 be used to identify the compressed payload. The meaning of byte 4 shall depend on the values of bytes 2 and 3 as shown in Table 3. Table 2 Payload Identifier Definition for SMPTE 352M Bits Byte 1 Byte 2 Byte 3 Byte 4 Bit 7 1 0 (Interlaced transport) 1 Image aspect ratio: 16:9 0 Bit 6 0 0 (Interlace

34、d picture) Reserved 0 Bit 5 1 00 (VC-2 low-delay syntax compression) Reserved 0 Bit 4 1 Reserved 0 Bit 3 0 Picture Rate (see SMPTE 352M Table 2) 0h (Sampling structure: 4:2:2 Y/Cb/Cr) 0 Bit 2 0 0 Bit 1 0 0 Bit 0 0 1 Table 3 Compressed Payload Formats Byte 2, bits 4 and 5 shall be set to 00 to indica

35、te that VC-2 low delay syntax is used for the video compression data.part of the signal. Byte 4 shall be set to 01h to indicate the carriage of the VC-2 mezzanine compressed payload and the viewable video data according to this standard. Byte 2 Byte 3 Byte 4 SMPTE 274M System no. System nomenclature

36、 00001011 (Picture rate = 60Hz) 10000000 00000001 1 1920 1080p 60 00001010h (Picture rate = 60/1.001 Hz) 10000000 00000001 2 1920 x 1080p 59.94 00001001h (Picture rate = 50Hz) 10000000 00000001 3 1920 x 1080p 50 SMPTE 2047-2:2010 Page 6 of 11 pages 4.7 Viewable Content A signal coded in accordance w

37、ith this interface will produce a recognizable version of the compressed payload (although noisy and coarsely quantised) when decoded and displayed by a SMPTE 292 compliant receiving interface, as if it were a standard 1920 x 1080/60/I, 1920 x 1080/59.94/I, or 1920 x 1080/50/I interlaced signal. 5 V

38、C-2 Mezzanine Bit-stream Mapping This section defines which data from a VC-2 stream according to SMPTE RP 2047-1 is mapped into the SDI signal. A compressed VC-2 stream comprises data and metadata. The metadata describes the parameters of the coded signal and the way in which it is encoded. The data

39、 describes the details of the specific video signal that has been compressed. When a VC-2 stream is transported over an SDI link, according to this specification, the stream metadata shall be inferred from the payload identifier (see Section 4.6). Therefore, it is only the data from the VC-2 stream

40、that is mapped to the SDI link. The signal data part of a VC-2 stream shall comprise the transform data part as defined in SMPTE ST 2042-1, VC-2 Video Compression. The transform data part of the VC-2 stream is defined in Sections 12.4 and 12.5 of the VC-2 specification. The transform data for each V

41、C-2 picture shall be mapped into exactly one interlaced picture area within the SDI signal. No metadata from the VC-2 stream shall be mapped into the SDI signal (except by inference from the payload identifier). Consecutive VC-2 pictures shall be mapped to consecutive SDI fields. The complete VC-2 s

42、tream (with the exception of VC-2 “Picture Numbers” defined in Section 11.1 of the VC-2 specification) can be reconstructed from the “Transform Data” present on the SDI and the metadata inferred from the payload identifier. VC-2 “Picture Numbers” provide unique identifiers for pictures within a sequ

43、ence. Picture numbers within a VC-2 sequence are required to increment by one for each successive picture within a given sequence. Between sequences they are unconstrained and so picture numbers, starting from any arbitrary value, may be inserted in a decoded VC-2 stream while retaining compliance w

44、ith the specification. Decoding apparatus may decode the VC-2 stream implied as in the previous paragraph to produce an uncompressed video signal. Note: The coding parameters, defined in SMPTE RP 2047-1, VC-2 Compression of 1080P High Definition Video Sources for transport over 1.5 Gb/s SDI, ensure

45、that the compressed “Transform Data”, plus the bits added for the viewable picture occupy precisely the space allocated within the SDI signal for the active picture. 6 Interface Data Format 6.1 Compressed Data Mapping The VC-2 mezzanine compressed video data shall be transported in the least-signifi

46、cant 8 bits of the (10-bit) video words as shown in Table 4. The first video word shall contain the first byte of the VC-2 “Transform Data”. Subsequent bytes of the “Transform Data” shall be transported in the 8 least-significant bits of consecutive video words, irrespective of whether the video wor

47、ds correspond to Cb, Y or Cr data. No compressed data shall be transported other than as the low 8 bits of video words. SMPTE ST 2047-2:2010 Page 7 of 11 pages Table 4 Mapping of compressed video data to interface words Word Bit number 9 (MSB) 8 7 6 5 4 3 2 1 0 (LSB) XYZ (C) 1 F 0 0 P3 P2 P1 P0 0 0

48、XYZ (Y) 1 F 0 0 P3 P2 P1 P0 0 0 Cb data Byte 0 of VC-2 Transform Data Y data Byte 1 of VC-2 Transform Data Cr data Byte 2 of VC-2 Transform Data Y data Byte 3 of VC-2 Transform Data Cb data Byte 4 of VC-2 Transform Data Y data Byte 5 of VC-2 Transform Data Cr data Byte 6 of VC-2 Transform Data Y dat

49、a Byte 7 of VC-2 Transform Data (MSB Most Significant Bit, LSB Least Significant Bit, MS Most Significant, LS Least Significant) The shaded region, the 2 most-significant bits of each video word, contains the viewable picture information as described in Section 6.2 below. Note: Since this specification uses the low delay syntax in accordance with SMPTE RP 2047-1, the 64 bytes of coefficient data for each slice