SMPTE ST 2016-4-2014 Vertical Ancillary Data Mapping of Pan-Scan Information.pdf

1、 Copyright 2014 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved August 16, 2014 Table of Contents Page Foreword 2 Intellectual Property . 2 Introduction. 2 1 Scope . 3 2 Conformance Notation . 3 3 Normative References . 3 4 Fo

2、rmat of VANC Data Packets 3 4.1 UDW Format . 4 5 Location of the Vertical Ancillary Data . 5 Annex A Bibliography (Informative) . 7 Annex B Comments on the Preferred Location of VANC Packets (Informative) . 8 Figures Figure 1 Data structure of Pan-Scan ANC Packet (type 2) 5 Tables Table 1 ANC Data P

3、ayload . 4 Table 2 Ancillary data packet structure . 5 Page 1 of 8 pages SMPTE ST 2016-4:2014 Revision of SMPTE 2016-4-2007 SMPTE STANDARD Vertical Ancillary Data Mapping of Pan-Scan Information SMPTE ST 2016-4:2014 Page 2 of 8 pages Foreword SMPTE (the Society of Motion Picture and Television Engin

4、eers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States of America, SMPTE has members in over 80 countries on six continents. SMPTEs Engineering Documents, including Standards, Recommended Practices and Engineering Guidelines, are

5、 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-developing organizations, including ISO, IEC and ITU. SMPTE Engineering Documents are drafted in accordance with the rule

6、s given in its Standards Operations Manual. SMPTE ST 2016-4 was prepared by Technology Committee 24TB. Intellectual Property At the time of publication no notice had been received by SMPTE claiming patent rights essential to the implementation of this Engineering Document. However, attention is draw

7、n 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 rights. Introduction Image formatting information describes certain spatial characteristics of a high definition or standard

8、 definition video image. It is generated and carried through all or some of the video production, distribution, and emission chain. The image formatting metadata types are Active Format Description (AFD), Bar Data, and Pan Scan information. AFD and Bar Data are intended to be broadcast with the vide

9、o signal that they describe. AFD information is intended to guide DTV receivers and/or intermediate professional video equipment regarding the display of video of one aspect ratio on a display of another aspect ratio. Bar Data information is used to signal the precise unused areas of an image raster

10、 when the active video does not completely fill that raster, in particular widescreen cinema material carried letterboxed in a frame with bars top and bottom. Pan-Scan information is a set of data that is intended to guide professional video equipment in extracting an image to be presented in an asp

11、ect ratio that is different from that in which the material was produced or distributed. Independent parameters are provided for pan (horizontal offset), tilt (vertical offset), vertical size, horizontal size, and output aspect ratio. Pan-Scan information is not intended for use beyond the productio

12、n and distribution environments. The following suite of SMPTE standards defines the origination and carriage of AFD, Bar Data, and Pan-Scan information: SMPTE ST 2016-1 Format for Active Format Description and Bar Data SMPTE ST 2016-2 Format for Pan-Scan Information SMPTE ST 2016-3 Vertical Ancillar

13、y Data Mapping of Active Format Description and Bar Data SMPTE ST 2016-4 Vertical Ancillary Data Mapping of Pan-Scan Information Other SMPTE standards can be used for alternative transport methods for this data. SMPTE ST 2016-4:2014 Page 3 of 8 pages 1 Scope This Standard defines a method of coding

14、that allows Pan-Scan information to be carried in the 10-bit vertical ancillary (VANC) data space of a standard definition or high definition bit-serial component television signal. The standard defines how the Pan-Scan information is placed into an ancillary data packet for carriage in accordance w

15、ith SMPTE ST 291-1. An associated standard, SMPTE ST 2016-2, defines the format for Pan-Scan information and identifies the video image and interface standards with which it is associated. 2 Conformance Notation Normative text is text that describes elements of the design that are indispensable or c

16、ontains 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. Informative text does not contain any conformance key

17、words. All text in this 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 documen

18、t 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 preferred but not necessarily required; or that (

19、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 that is not defined at this time, shall not be us

20、ed, 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. 3 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this

21、recommended practice. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this recommended practice are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below.

22、 SMPTE ST 291-1:2011, Television Ancillary Data Packet and Space Formatting SMPTE ST 2016-2:2014, Format for Pan-Scan Information SMPTE RP 168:2009, Definition of Vertical Interval Switching Point for Synchronous Video Switching 4 Format of VANC Data Packets Each data packet shall comply with the fo

23、rmat defined in SMPTE ST 291-1 for a type 2 ANC packet. It consists of the ancillary data flag (ADF), the data ID (DID), the secondary data ID (SDID), the data count (DC), the user data words (UDW), and the checksum (CS). The UDW consists of the data payload. SMPTE ST 2016-4:2014 Page 4 of 8 pages T

24、he DID word shall be set to the value 41h. The SDID word shall be set to the value of 06h. DC is a count of the number of words in the UDW and shall be set to a fixed value of 96 (60h). 4.1 UDW Format Eight Pan-Scan Data Sets shall be carried in the User Data Words of a SMPTE ST 291-1 ancillary data

25、 packet, each Pan-Scan Data Set as shown in Table 1. The format of the Pan-Scan data bytes shall be as defined in Section 7.1 of SMPTE ST 2016-2. The Pan-Scan information shall be transmitted in bits b7 through b0 of the 10-bit data word. Bit b8 is even parity for bits b7 through b0 of the 10-bit da

26、ta word, and bit b9 equals not bit b8. Table 1 ANC Data Payload per Data Set Data Set Words User Data Word bits Function b9 b8 b7 b6 b5 b4 b3 b2 b1 b0 1 Data Set ID b8 P id7 id6 id5 id4 id3 id2 id1 id0 2 Pan-Scan Flags b8 P Pan Tilt Vert Horiz rsv ar2 ar1 ar0 3 Pan Horizontal offset b8 P p15 p14 p13

27、 p12 p11 p10 p9 p8 4 b8 P p7 p6 p5 p4 p3 p2 p1 p0 5 Tilt Vertical offset b8 P t15 t14 t13 t12 t11 t10 t9 t8 6 b8 P t7 t6 t5 t4 t3 t2 t1 t0 7 Vertical size b8 P 0 0 v13 v12 v11 v10 v9 v8 8 b8 P v7 v6 v5 v4 v3 v2 v1 v0 9 Horizontal size b8 P 0 0 h13 h12 h11 h10 h9 h8 10 b8 P h7 h6 h5 h4 h3 h2 h1 h0 11

28、 Reserved b8 P 0 0 0 0 0 0 0 0 12 Reserved b8 P 0 0 0 0 0 0 0 0 where: Pan, Tilt, Vert id7 - id0 is the Pan-Scan Data Set ID code (see SMPTE ST 2016-2 Section 7.1.1); ar2 - ar0 is the output image aspect ratio code (see SMPTE ST 2016-2 Section 7.1.2); p15 - p0 is the Horizontal viewport offset (see

29、SMPTE ST 2016-2 Section 7.1.3); t15 - t0 is the Vertical viewport offset (see SMPTE ST 2016-2 Section 7.1.3); v13 - v0 is the Vertical size coefficient (see SMPTE ST 2016-2 Section 7.1.3); h13 - h0 is the Horizontal size coefficient (see SMPTE ST 2016-2 Section 7.1.3); rsv is reserved and set to 0 (

30、see SMPTE ST 2016-2 Section 7.1.2) P is the even parity bit for b7 through b0. Table 2 outlines the ancillary data packet words with values where appropriate. The total size of the ancillary data packet is 103 words. SMPTE ST 2016-4:2014 Page 5 of 8 pages Table 2 Ancillary data packet structure Name

31、 Acronym Value Ancillary data flag (10-bit words) ADF 000h, 3FFh, 3FFh Data identification DID 41h Secondary data identification SDID 06h Data count DC 60h Pan-Scan Data Sets 1-8 (96 words) UDW Checksum CS A nci ll ar yData FlagData I DS econdar yData I DDataCou ntChe c k s umB it b9 = I nverse of b

32、it b8B it b8 = P ar it y ( b7 t o b0)D at aSet110bits8bitsSDIDDCAD FDID D at aSet2CSb0b9b8b7D at aSet8Figure 1 Data structure of Pan-Scan ANC Packet (type 2) 5 Location of the Vertical Ancillary Data The ANC data packet(s) containing Pan-Scan and other information shall be located in the active line

33、 portion of one line in the vertical ancillary space. Data may be located in any lines in the area from the second line after the line specified for switching, as defined in SMPTE RP 168, to the last line before active video, inclusive. In order to maximize the time available for processing the acti

34、ve video with which pan-scan information is associated, Pan-Scan data should be located early in the VANC period (see Annex B for further guidance). The data packets shall be associated with the video frame that is being described and shall be present for every frame. SMPTE ST 2016-4:2014 Page 6 of

35、8 pages Pan-Scan information, when coded as ancillary data, shall be placed in the VANC such that: 1. for natively generated interlaced video system signals, the Pan-Scan information for the first and second fields of the same frame shall be identical; 2. for interlace video signals derived from 24p

36、 image sequences, the Pan-Scan information for each field shall be identical to the Pan-Scan information for the image from which it was derived; 3. for progressive segmented frame systems, the Pan-Scan information signalled for the first and second segments of the same frame shall be identical. Whe

37、n the ANC packets defined in this standard are carried in a high definition or UHDTV signal, they shall be carried in the Y stream. For further details see SMPTE ST 292-1 and SMPTE ST 2036-3. Receiving equipment should identify the ANC packets on the basis of their ANC DID and SDID fields. Note: Des

38、igners are advised that although this standard specifies VANC as the location for the transport of information in an SD-SDI interface, there are legacy devices that will not pass this information if it is located on video lines where the V-bit (see SMPTE ST 125) is set to logical one. SMPTE ST 2016-

39、4:2014 Page 7 of 8 pages Annex A Bibliography (Informative) SMPTE ST 125:2013, SDTV Component Video Signal Coding 4:4:4 and 4:2:2 for 13.5 MHz and 18 MHz Systems SMPTE ST 292-1:2012, 1.5 Gb/s Signal/Data Serial Interface SMPTE ST 352:2013, Payload Identification Codes For Serial Digital Interfaces S

40、MPTE EG 43:2004, System Implementation of CEA-708-B and CEA-608-B Closed Captioning and Program-Related Data SMPTE RP 291-2:2013, Ancillary Data Space Use 4:2:2 SDTV and HDTV Component Systems and 4:2:2 2048 1080 Production Image Formats SMPTE ST 2016-4:2014 Page 8 of 8 pages Annex B Comments on the

41、 Preferred Location of VANC Packets (Informative) Notwithstanding the possibility that the VANC packets can be placed on any line in the vertical blanking interval, it is desirable to further constrain the location to a preferred line to improve the probability of successful passage through the prod

42、uction process. System designers are advised that many devices in the studio processing chain will pass data on only a small subset of lines in the vertical ancillary space and some devices (e.g., production switchers, digital video effects units, and video servers) might not pass VANC packets at al

43、l. This must be taken into account in the distribution system design and choice of data location in VANC. Some recording devices record only one line of data from the vertical blanking interval while others will record up to 11 lines. However, it is a common practice to set them to record three cons

44、ecutive lines starting at the second line after the switching line. This constrains the available lines to the second line, the third line, and the fourth line after the switching line. It has been observed that some devices do not test for existing ANC packets and consequently overwrite existing AN

45、C packets. These devices might insert data on any line after the switching line. ANC packets containing Pan-Scan are preferably embedded with the video signal early in the production process. To reduce the risk of this data being blocked or overwritten by other devices it is suggested that these ANC

46、 packets be placed on the fourth line after the switching lines defined in SMPTE RP168. Users can have their own priorities for determining the optimum location of the ANC packet, which could result in a different line being selected. Similar considerations apply for closed captioning and other data services carried in VANC, as discussed in SMPTE EG 43.