1、 Approved June 5, 2015 Copyright 2015 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Table of Contents Page Foreword 2 Intellectual Property . 2 Introduction. 2 1 Scope 3 2 Conformance Notation 3 3 Normative References 3 4 Timing Refe
2、rence Application . 4 4.1 Output Reference . 4 4.2 Input Reference 4 4.3 Relative Timing. 4 5 General Characteristics. 4 5.1 Signal Characteristics . 4 5.2 Active Picture Signal Level . 4 5.3 Sync and Burst Jitter 5 5.4 Master Oscillator Frequency 5 5.5 Connectors . 5 5.6 Impedance 5 6 Ancillary Sig
3、nals 5 6.1 Vertical Interval Time Code 5 6.2 Ten-Field Reference (60/1.001 Hz Related Systems only) . 5 6.3 Compliance Nomenclature . 7 7 Notes (Informative) 7 Annex A Bibliography (Informative) . 8 SMPTE ST 318:2015 Revision of SMPTE 318M-1999 SMPTE STANDARD Synchronization of 59.94- or 50-Hz Relat
4、ed Video and Audio Systems in Analog and Digital Areas Reference Signals Page 1 of 8 pages SMPTE ST 318:2015 Page 2 of 8 pages Foreword SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in
5、 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 prepared by SMPTEs Technology Committees. Participation in these Committees is open to all with a bona fi
6、de 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 rules given in its Standards Operations Manual. This SMPTE Engineering Document was prepared by Technology Com
7、mittee 32NF. 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 drawn to the possibility that some of the elements of this document may be the subject of pate
8、nt rights. SMPTE shall not be held responsible for identifying any or all such patent rights. Introduction This section is entirely informative and does not form an integral part of this Engineering Document. Composite and component video equipment frequently requires an external reference signal fo
9、r synchronization. The use of digital video and audio signals places additional reliance on the reference to avoid buffer management problems, manage jitter, and maintain a defined relationship between video and audio signals. Color black is the external reference signal used traditionally for analo
10、g NTSC and PAL equipment. This standard specifies a compatible extension of the color black signal to extend its application to digital equipment operating at most frequency related standards. SMPTE ST 318:2015 Page 3 of 8 pages 1 Scope This standard specifies the use of a derivative of a color blac
11、k signal as a reference for the synchronization of all forms of composite or component, digital or analog equipment using a system standard related to 60/1.001 (nominal 59.94) or 50 Hz. It also provides the option for the reference signal to carry VITC. This will allow the reference to distribute lo
12、cal or UTC time data. In the case of the reference for 60/1.001 Hz related signals, the signal may carry optionally a ten-field sequence identification signal. This facilitates interworking with equipment operating at related rates (e.g. 24/1.001 (nominal 23.98) Hz or 48 kHz). Note: SMPTE ST 12-1 An
13、nex B gives guidance on conversion of 24/1.001 (23.98) frames-per-second video to 30/1.001 (29.97) frames-per-second video using the ten-field sequence. 2 Conformance Notation Normative text is text that describes elements of the design that are indispensable or contains the conformance language key
14、words: “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 this document is,
15、 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 deviation is per
16、mitted. 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) a certain poss
17、ibility 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 defined in the future
18、. 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 provisions (“should“) a
19、s 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 information in this document shall be as follows: Normative prose shall be the authoritative
20、 definition; Tables shall be next; then formal languages; then figures; and then any other language forms. 3 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this recommended practice. At the time of publication, the edit
21、ions 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. SMPTE ST 12-1:2014, Time and Control Code SMPTE ST 318:20
22、15 Page 4 of 8 pages SMPTE ST 170:2004 (Stabilized 2010), Television Composite Analog Video Signal NTSC for Studio Applications IEC 61169-8 Ed1.0 (2007-02), Radio-Frequency Connectors Part 8: Sectional Specification RF Coaxial Connectors with Inner Diameter of Outer Conductor 6,5 mm (0,256 in) with
23、Bayonet Lock Characteristic Impedance 50 ohm (Type BNC) Recommendation ITU-R BT.1700 (2005), Characteristics of Composite Video Signals for Conventional Analogue Television Systems 4 Timing Reference Application 4.1 Output Reference Where a separate reference is required for the output function, the
24、 equipment may derive its timing reference for the output function from a signal as defined in this standard. 4.2 Input Reference For equipment that stores video with variable delay (i.e., video recorders, synchronizers, and time-base correctors) or that monitors video, the equipment may derive its
25、timing reference for the input function from the input video or from a reference signal as defined in this standard. 4.3 Relative Timing Some equipment, e.g. routing switchers, may use the reference signal to derive a trigger for switching. Vertical interval switching points for various standard def
26、inition and high definition video systems are defined in SMPTE RP 168. 5 General Characteristics The reference signal is defined as follows: 5.1 Signal Characteristics The signal waveform shall conform to the system specifications as defined in SMPTE ST 170 or Recommendation ITU-R BT.1700, as approp
27、riate, except as noted herein. The signal shall include the appropriate color burst. 5.1.1 60/1.001 Hz related 525 line; 2:1 interlace; 30/1.001 frames/s; (60/1.001 fields/s); 3.58 MHz (nominal) subcarrier burst (NTSC). 5.1.2 50 Hz related 625 line; 2:1 interlace; 25 frames/s; (50 fields/s); 4.43 MH
28、z (nominal) subcarrier burst (PAL). 5.2 Active Picture Signal Level The signal level throughout the active picture period shall correspond to black level (see Section 7, Notes 1 and 2). SMPTE ST 318:2015 Page 5 of 8 pages 5.3 Sync and Burst Jitter The timing of individual leading edges of horizontal
29、 synchronization pulses at the reference generator output shall be within 2 ns peak to peak, measured over at least one field (see Section 7, Note 3). The zero-crossing points of color burst subcarrier shall be within 500 ps peak to peak measured over at least one field. 5.4 Master Oscillator Freque
30、ncy The color subcarrier frequency should remain within 1 Hz of its nominal value. The rate of change should not exceed 0.1 Hz/s. 5.5 Connectors 75 ohm BNC connectors shall be in accordance with IEC 61169-8. 5.6 Impedance The reference signal source impedance shall be 75 ohms. Return loss shall be g
31、reater than 40 dB from 25 Hz to 10 MHz. 6 Ancillary Signals The reference signal may include signals for the transport of additional information to facilitate timing and synchronization with other systems. This ancillary information should be coded to avoid excessive disturbance to the average pictu
32、re level (see Section 7, Note 2). 6.1 Vertical Interval Time Code Vertical Interval Time Code (VITC) may be added on lines 14 and 277 only for 525/59.94 (NTSC) systems or lines 19 and 332 only for 625/50 (PAL) systems. If present, the Vertical Interval Time Code shall be in accordance with SMPTE ST
33、12-1. 6.2 Ten-Field Reference (60/1.001 Hz Related Systems only) For 60/1.001-Hz related systems (e.g., 525-line NTSC), a signal to establish a unique ten-field sequence may be added using lines 15 and 278. A pulse coded waveform identifies each field over a ten-field (five-frame) sequence. 6.2.1 Te
34、n-Field Sequence Identification If present, the ten-field (five-frame) sequence identification shall be coded over 6 pulse positions as shown in Table 1. The Start pulse (position 1) shall always be present. The Frame Count Pulses (positions 2 through 5) indicate the frame number within the sequence
35、, the number of pulses increasing from zero to four during the sequence. The Field Pulse (position 6) shall indicate odd field (pulse absent) or even field (pulse present). The pulses shall be present on both line 15 and line 278 with the exception of the even-field identification pulse which is pre
36、sent on line 278 (even field) only. Pulse positions shall be separated by spaces of duration equal to the pulses. The waveform is shown in Table 1. SMPTE ST 318:2015 Page 6 of 8 pages The start of the ten-field sequence shall be the field with zero frame count pulses and no even-field identification
37、 pulse, i.e. pulse logical values 1, 0, 0, 0, 0, 0. Table 1 Pulse coding for ten-field sequence Ten-field Sequence Five-Frame Sequence Start Pulse 1 Frame Count Pulses Field Pulse 6 Pulse 2 Pulse 3 Pulse 4 Pulse 5 1 1 1 0 0 0 0 0 2 1 0 0 0 0 1 3 2 1 1 0 0 0 0 4 1 1 0 0 0 1 5 3 1 1 1 0 0 0 6 1 1 1 0
38、0 1 7 4 1 1 1 1 0 0 8 1 1 1 1 0 1 9 5 1 1 1 1 1 0 10 1 1 1 1 1 1 Note: Implementers should be aware that the Frame of Sequence numbers are one-based; however, the Frame Count Pulse coding is zero-based. 6.2.2 Pulse waveshape, position and jitter The pulse edges should be skew-symmetric. Raised cosin
39、e shaping is preferred. Other signal parameters shall be as specified in Figure 1 and Table 2. Figure 1 Ten-field identification signal SMPTE ST 318:2015 Page 7 of 8 pages Table 2 Ten-field identification pulse parameters Parameters Value Tolerance Units Logic 0 level 0 0 + 5 IRE 1) Logic 1 level 40
40、 5 IRE 1) Pulse width 2.22 0.10 s 2) Pulse edge 10% - 90% 140 20 ns Pulse edge jitter 2 nsp-p H-sync to first pulse 11.11 0.2 s Notes: 1) IRE units are specified in SMPTE ST 170. 2) A basic clock frequency of 4.5 MHz is assumed; the pulse width is related to the period of that clock. 6.3 Compliance
41、nomenclature The default compliance is defined as a signal containing no ancillary information. A suffix letter or letters should be appended to indicate the addition of ancillary data. A reference signal including VITC would be said to conform to SMPTE ST 318-A. A reference signal including the ten
42、-field sequence identification would be said to conform to SMPTE ST 318-B. A reference signal including both VITC and the ten-field sequence identification would be said to conform to SMPTE ST 318-AB. 7 Notes (Informative) 1. In some parts of the world, a nominal value from 0 IRE to 10 IRE can be us
43、ed for the setup pedestal. 2. Reference signals of higher constant average picture level (APL) are specifically avoided because they can cause performance degradation related to APL variations between the vertical interval and other parts of the signal. Furthermore, reference signals with changing A
44、PL, such as moving video or switched test signals, are also specifically excluded because they can cause disturbances to the video signal being processed by the equipment for which they are the reference. Also, it has become a common practice to use the reference signal as a convenient source of a b
45、lack picture. In this case, it is recommended that the effect of permitted ancillary signals be considered. 3. Reference signals with minimal jitter are preferred for many applications. For example, SMPTE ST 259 specifies a worst-case figure for alignment and timing of jitter of 0.2 UI. SMPTE ST 318
46、:2015 Page 8 of 8 pages Annex A Bibliography (Informative) AES3-2009, AES Standard for Digital Audio Digital Input-Output Interfacing Serial Transmission Format for Two-Channel Linearly-Represented Digital Audio Data AES11-2009, AES Recommended Practice for Digital Audio Engineering Synchronization
47、of Digital Audio Equipment in Studio Operations 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 244:2003, Television System M/NTSC Composite Video Signals Bit-Parallel Digital Interface SMPTE ST 259:2008, Television SDTV Digital Signal/D
48、ata Serial Digital Interface SMPTE ST 274:2008, Television 1920 1080 Image Sample Structure, Digital Representation and Digital Timing Reference Sequences for Multiple Picture Rates SMPTE ST 293:2003, Television 720 483 Active Line at 59.94-Hz Progressive Scan Production Digital Representation SMPTE
49、 ST 294:2001, Television 720 483 Active Line at 59.94-Hz Progressive Scan Production Bit-Serial Interfaces SMPTE ST 295:1997, Television 1920 1080 50-Hz Scanning and Interface SMPTE ST 296:2012, 1280 720 Progressive Image 4:2:2 and 4:4:4 Sample Structure Analog and Digital Representation and Analog Interface SMPTE ST 2059-1:2015, Generation and Alignment of Interface Signals to the SMPTE Epoch SMPTE RP 168:2009, Definition of Vertical Interval Switching Point for Synchronous Video Switching
