PROPOSED SMPTE STANDARD for Television Dual Link 292M Interface for 1920 x 1080 Picture Raster SMPTE 372M Page 1 of 16 pages Table of contents 1 Scope 2 Normative references 3 General 4 Source signal formats 5 Interface general 1 Scope This standard defines a means of interconnecting digital video equipment with a dual link HD SDI (link A and link B), based upon the SMPTE 292M data structure. The source formats for this dual link interconnection are the picture raster formats, and digital interface representations as defined in SMPTE 274M. The total data rate of the dual link connection is 2.970 Gb/s or 2.970/1.001 Gb/s. This dual link also supports carriage of the embedded audio, the ancillary data and the ID of the stream. NOTE This may not the only mapping onto the dual link 292M. It is likely that other image formats will be mapped onto the dual link 292M. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this practice. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this practice are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below. ANSI/SMPTE 299M-1997, Television 24-Bit Digital Audio Format for HDTV Bit-Serial Interface SMPTE 274M-1998, Television 1920 x 1080 Scanning and Analog and Parallel Digital Interfaces for Multiple Picture Rates SMPTE 291M-1998, Television Ancillary Data Packet and Space Formatting SMPTE 292M-1998, Television Bit-Serial Digital Interface for High-Definition Television Systems SMPTE 294M-2001, Television 720 x 483 Active Line at 59.94-Hz Progressive Scan Production Bit- Serial Digital Interfaces Copyright 2002 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 595 W. Hartsdale Ave., White Plains, NY 10607 (914) 761-1100 THIS PROPOSAL IS PUBLISHED FOR COMMENT ONLY
SMPTE 352M, Television (Dynamic) Video Payload Identification for Digital Interfaces SMPTE RP 157-1995, Key Signals SMPTE RP 175-1997, Digital Interface for 4:4:4:4 Component Video Signals (Dual Link) SMPTE RP 188-1999, Transmission of Time Code and Control Code in the Ancillary Data Space of a Digital Television Data Stream SMPTE RP 211-2000, Implementation of 24P, 25P and 30P Segmented Frames for 1920x1080 Production Format 3 General 3.1 This dual link standard is intended to extend SMPTE 292M applications to include R G B, 10- and 12-bit source signals, as well as to provide for the carriage of an additional alpha channel of data up to a maximum of 2.970 Gb/s. 3.1.1 When 60P/4:2:2/10-bit signals are present, data in the Y C B C R format (4:2:2P) are transparently divided line sequentially into two data streams, each equivalent to a 4:2:2 component signal that can be transported by SMPTE 292M. 3.1.2 When R G B +A 10-bit signals are present, link A carries all the G samples plus B and R evennumbered samples. Link B carries the B and R odd-numbered samples, and, if present, the samples of the alpha channel. 3.1.3 When R G B 12-bit signals are present, link A carries the most significant 10 bits of all the G samples plus the most significant 10 bits of B and R even-numbered samples. Link B carries the most significant 10 bits of the B and R odd-numbered samples, plus the least significant 2 bits of the R G B samples which are mapped to the alpha channel. 3.1.4 When Y C B C R A (4:4:4:4) 10-bit or Y C B C R (4:4:4) 12-bit signals are present, the data structure of link A and link B shall be the same with ones of R G B +A 10-bit or R G B 12-bit, respectively. 3.1.5 When 4:2:2 (Y C B C R A) 12-bit signals are present, link A carries the most significant 10 bits of all the Y samples plus the most significant 10 bits of C B and C R even-numbered samples. Link B carries the least significant 2 bits of the Y, C B and C R even-numbered samples, plus the least significant 2 bits of the Y (only) at odd-numbered samples plus the alpha channel. 3.2 Mapping of payload data onto the interface is based upon SMPTE 294M or SMPTE RP 175. 3.3 Reference is made in this standard to an A channel, defined as the alpha channel. 4 Source signal formats The source signal formats used by this standard are defined in Table 1. Page 2 of 16 pages
Table 1 Source signal formats Signal format sampling structure/pixel depth Frame/field rates 4:2:2 (Y C B C R )/10-bit 60, 60/1.001 and 50 progressive 4:4:4 (R G B ), 4:4:4:4 ( R G B +A [see note] ) /10-bit 30, 30/1.001, 25, 24, and 24/1.001 4:4:4 (R G B )/12-bit Progressive, PsF 4:4:4 (Y C B C R ), 4:4:4:4 ( Y C B C R +A [ see note] ) 60, 60/1.001, and 50 fields Interlaced /10-bit 4:4:4 (Y C B C R )/12-bit 4:2:2 (Y C B C R )/12-bit NOTE Definition of the A channel is application-dependent. In the cases when the A channel is used for non -picture data, the payload is constrained to 8-bit words maximum. 4.1 4:2:2 (Y C B C R )/10-bit signals, at 60, 60/1.001 and 50 progressive frames/s 4.1.1 Interface data streams Mapping of the data created by the 4:2:2 picture sampling structure is shown in figures 1 and 2. Each line of the source picture raster is alternately mapped between link A and link B of the dual interface (see also SMPTE 294M). 4.1.2 Timing reference signals and line numbers The F (field/frame), V (vertical), H (horizontal), P3, P2, P1, P0 (parity) bits and the line numbers of link A and link B shall be as shown in figures 1 and 2. (The line numbers as carried by the 292M interfaces shall be in accordance with the 292M-interface definition, not the picture source line numbers.) NOTES 1 Buffering having a minimum duration of one horizontal line is required by this process at each interface, making a minimum transmission delay of two horizontal lines. 2 Figure 1 shows how the luminance and color-difference signals are multiplexed within a transmission package. Page 3 of 16 pages
Y' stream SAV SAV SAV SAV C'BD0 C'RD959 SAV SAV SAV SAV Y'D0 Y'D1919 a b c d a C'B/C'R stream a b c d a Transmission package (length 2H, see Note) The above figure shows the 4:2:2P data structure. Word number Frame Total words per transmission Total words of active image data per a b c d rate package transmission package 60 or 2200 1920 1920 2196 0 1919 60/1.001 50 2640 1920 1920 2636 0 1919 NOTE H denotes one line period of the original 60, 60/1.001 and 50 progressive signals as specified by SMPTE 274M. Figure 1 Multiplexed horizontal data stream Page 4 of 16 pages
NOTES 1 1125 progressive line numbers as defined in SMPTE 274M. 2 1125 interlace digital line numbers are defined in SMPTE 274M. The line number carried on the interface shall be the interface line number, not the picture source line number. Figure 2 Dual-link interface line numbering and packaging Page 5 of 16 pages
4.2 4:4:4 (R G B ) and 4:4:4:4 (R G B +A)/10-bit signals, at 30, 30/1.001, 25, 24 and 24/1.001 frame rates, and at 60, 60/1.001 and 50 field rates 4.2.1 Source sample numbering Each line of the R G B and A channel consists of 2750, 2640 or 2200 total samples. The samples are designated 0-2749, 0-2639, or 0-2199 and the individual samples are designated by suffixes such as sample G 135 or sample B 429 (see also SMPTE RP 175). 4.2.2 Interface data streams Link A data stream contains all the G channel samples plus the even-numbered (0, 2, 4, etc.) samples from the B and R channels. Link B data stream contains the odd-numbered (1, 3, 5, etc.) samples from the B and R channels plus all the A-channel samples (see figure 3). 4.2.3 Multiplex structure The video data words shall be conveyed in the following order: Link A data stream: B 0, G 0, R 0, G 1, B 2, G 2, R 2, G 3 Link B data stream: B 1, A0, R 1, A1, B 3, A2, R 3, A3 See figures 3 and 4. Page 6 of 16 pages
Last Sample of Digital Active Line First Sample of Digital Active Line a G' B' R' A LINK A LINK B B'1919 R'1919 B'1 R'1 A1918 A1919 3FF(A) XYZ(A) 3FF(A) XYZ(A) A0 A1 B'1918 R'1918 B'0 R'0 G'1918 G'1919 3FF(G) 000(G) 000(G) XYZ(G) 3FF(G) 000(G) 000(G) XYZ(G) G'0 G'1 Frame/Field Rates/ Pixel Depth 60 or 60/1.001 fields, 30 or 30/1.001 frames; 10-bit 50 fields, 25 frames; 10-bit 24 or 24/1.001 frames; 10-bit Total words per transmission package Total words of active image data per transmission package Word number a 2200 1920 2199 2640 1920 2639 2750 1920 2749 Figure 3 Multiplex structure Page 7 of 16 pages
SAMPLE NUMBER 0 1 2 3 4 5 G' G' G' G' G G' LINK A B' B' B' B' B' B' R' R' R' R' R' R' LINK B A A A A A A Figure 4 Channel representation for R G B +A 10-bit 4.2.4 Alpha channel If the alpha (A) signal is not used, the values of the alpha channel samples shall be set to 64 h. Use of the alpha channel is application dependent. 4.2.4.1 If the alpha channel is used for conveying picture information, the raster format and frame rate shall be the same as the R G B signals carried on the interface. 4.2.4.2 If the alpha channel is used to carry data, the data words shall be 8-bit maximum. 4.2.4.3 Data values 000 h to 003 h and 3FC h to 3FF h shall not be permitted. 4.3 4:4:4 (R G B ) 12-bit signals, at 30, 30/1.001, 25, 24 and 24/1.001 frame rates, and at 60, 60/1.001 and 50 field rates 4.3.1 Source sample numbering Each line of G, B, and R signals consists of 2750, 2640 or 2200 total samples. The samples are 12-bit quantized and designated 0-2749, 0-2639 or 0-2199. The individual samples are designated by suffixes such as sample G 135 or sample B 429. The most significant 10 bits of the 12-bit samples are designated by suffixes such as sample G 135:2-11 or sample B 429:2-11, and the least significant 2 bits of 12-bit samples are designated by suffixes such as sample G 135:0-1 or sample B 429:0-1. The least significant 2 bits of the R G B signals are mapped to the A (alpha) channel, and are designated by suffixes such as R G B 135:0-1. The nth bit of R G B signals is designated by a suffix such as G :n. The R G B n:0-1 data structure is defined in 4.3.3. 4.3.2 Interface data streams Link A data stream contains the most significant 10 bits of all the G channel samples, plus the most significant 10 bits of the even-numbered (0, 2, 4, etc.) samples in the B and R channels. Link B data stream contains the most significant 10 bits of odd-numbered (1, 3, 5, etc.) samples in the B and R channels, plus the least significant 2 bits from all the samples in the R, G and B channels (see figure 5). 4.3.3 R G B n:0-1 alpha channel data mapping Mapping of the least significant 2 bits from R, G and B onto the alpha channel of link B is shown in table 2. Page 8 of 16 pages
Last Sample of Digital Active Line G' First Sample of Digital Active Line a B' R' LINK A LINK B B'1919:2-11 R'1919:2-11 B'1:2-11 R'1:2-11 R'G'B'1918:0-1 R'G'B'1919:0-1 3FF(A) XYZ(A) 3FF(A) XYZ(A) R'G'B'0:0-1 R'G'B'1:0-1 B'1918:2-11 R'1918:2-11 B'0:2-11 R'0:2-11 G'1918:2-11 G'1919:2-11 3FF(G) 000(G) 000(G) XYZ(G) 3FF(G) 000(G) 000(G) XYZ(G) G'0:2-11 G'1:2-11 Frame/Field rate/ Pixel Depth Total words per transmission package Total words of active image data per transmission package Word number a 60 or 60/1.001 fields, 30 or 30/1.001 frames; 12-bit 50 fields, 25 frames; 12-bit 24 or 24/1.001 frames; 12-bit 2200 1920 2199 2640 1920 2639 2750 1920 2749 Figure 5 Multiplex structure Page 9 of 16 pages
Table 2 R G B n:0-1 alpha channel mapping structure Bit number Word 9 8 7 6 5 4 3 2 1 0 (MSB) (LSB) B8 EP G n:1 G n:0 B n:1 B n:0 R n:1 R n:0 Res Res NOTES 1 MSB: most significant bit. 2 LSB: least significant bit. 3 B8 is the even parity for B7 through B0. 4 B9 is the complement of B8. 5 B0 and B1 are the reserved bits (reserved bits shall be set to 0 until defined). 4.3.4 Multiplex structure The video data words shall be conveyed in the following order: Link A data stream: B 0:2-11, G 0:2-11, R 0:2-11, G 1:2-11, B 2:2-11, G 2:2-11, R 2:2-11, G 3:2-11 Link B data stream: B 1:2-11, R G B 0:0-1, R 1:2-11, R G B 1:0-1, B 3:2-11, R G B 2:0-1, R 3:2-11, R G B 3:0-1 See figure 6. SAMPLE NUMBER 0 1 2 3 4 5 G':2-11 G':2-11 G':2-11 G':2-11 G':2-11 G':2-11 LINK A B':2-11 B':2-11 B':2-11 B':2-11 B':2-11 B':2-11 R':2-11 R':2-11 R':2-11 R':2-11 R':2-11 R':2-11 LINK B R'G'B':0-1 R'G'B':0-1 R'G'B':0-1 R'G'B':0-1 R'G'B':0-1 R'G'B':0-1 Figure 6 Channel representation for R G B 12-bit 4.4 Y C B C R A signals, at 30, 30/1.001, 25, 24 and 24/1.001 frame rates, and at 60, 60/1.001 and 50 field rates 4.4.1.1 General This interface may be used to connect Y C B C R A (4:4:4:4) 10-bit signals, and Y C B C R (4:4:4) 10-bit or 12-bit signals. 4.4.1.2 Y C B C R (4:4:4), Y C B C R A (4:4:4:4) 10-bit Multiplex Structure When Y C B C R (4:4:4), Y C B C R A (4:4:4:4) 10-bit signals are used, the samples shall be sent as follows: The Y signals shall be sent in the sample locations referred to above as G ; The C B signals shall be sent in the sample locations referred to above as B ; The C R signals shall be sent in the sample locations referred to above as R ; The A signals shall be sent in the sample locations referred to above as A. Page 10 of 16 pages
Link A data stream: C B 0, Y 0, C R 0, Y 1, C B 2, Y 2, C R 2, Y 3 Link B data stream: C B 1, A0, C R 1, A1, C B 3, A2, C R 3, A3 See figure 7. SAMPLE NUMBER 0 1 2 3 4 5 Y' Y' Y' Y' Y Y' LINK A C' B C' B C' B C' B C' B C' B C' R C' R C' R C' R C' R C' R LINK B A A A A A A Figure 7 Channel representation for Y C B C R A 10-bit 4.4.1.3 Alpha channel See 4.2.4. 4.4.2.1 Y C B C R (4:4:4) 12-bit multiplex structure When Y C B C R (4:4:4) 12-bit signals are used, the nomenclature of Y n:2-11, C B n:2-11, C R n:2-11 and Y C B C R n:0-1 shall be defined as per Clause 4.3.1.The samples shall be mapped as follows: The Y n:2-11 signals shall be mapped to the sample locations referred to above as G n:2-11; The C B n:2-11 signals shall be mapped to the sample locations referred to above as B n:2-11; The C R n:2-11 signals shall be mapped to the sample locations referred to above as R n:2-11; The Y C B C R n:0-1 signals shall be mapped to the sample locations referred to above as R G B n:0-1. Link A data stream: C B 0:2-11, Y 0:2-11, C R 0:2-11, Y 1:2-11, C B 2:2-11, Y 2:2-11, C R 2:2-11, Y 3:2-11 Link B data stream: C B 1:2-11, Y C B C R 0:0-1, C R 1:2-11, Y C B C R 1:0-1, C B 3:2-11, Y C B C R 2:0-1, C R 3:2-11, Y C B C R 3:0-1 See figure 8. SAMPLE NUMBER 0 1 2 3 Y':2-11 Y':2-11 Y':2-11 Y':2-11 LINK A C' B :2-11 C' B :2-11 C' B :2-11 C' B :2-11 C' R :2-11 C' R :2-11 C' R :2-11 C' R :2-11 LINK B Y'C' B C' R :0-1 Y'C' B C' R :0-1 Y'C' B C' R :0-1 Y'C' B C' R :0-1 Figure 8 Channel representation for YC' B C' R (4:4:4) 12-bit Page 11 of 16 pages
4.5 4:2:2 (Y'C' B C' R ) 12-bit signals, at 30, 30/1.001, 25, 24 and 24/1.001 frame rates, and 60, 60/1.001 and 50 field rates 4.5.1 Y'C' B C' R (4:2:2) 12-bit multiplex structure This interface may also be used to connect Y C B C R (4:2:2) 12-bit signals. The nomenclature of Y n:2-11, C B n:2-11, C R n:2-11 and Y C B C R n:0-1 shall be defined as in Clause 4.3.1. 4.5.2 Interface data streams Link A data stream contains the most significant 10 bits of all the Y channel samples plus the most significant 10 bits of all the even-numbered C B, C R samples. Link B data stream contains the least significant 2 bits of Y, C B, C R samples at even-numbered sample points, and the least significant 2 bits of Y (only) at oddnumbered sample points, plus the A (alpha) channel (see figures 9 and 10). 4.5.3 Y'C' B C' R n:0-1, Y'n;0-1 Y' channel data mapping Mapping of the least significant 2 bits from the even-numbered samples of Y, C B and C R, and the least significant 2 bits from the odd-numbered samples of Y (only), onto the nominal Y channel of link B, is shown in tables 3 and 4 and figure 9. Table 3 Y'C' B C' R n:0-1 Y' channel mapping structure Bit number Word 9 8 7 6 5 4 3 2 1 0 (MSB) (LSB) B8 EP Y n:1 Y n:0 C B n:1 C B n:0 C R n:1 C R n:0 Res Res NOTES 1 MSB: most significant bit. 2 LSB: least significant bit. 3 B8 is the even parity for B7 through B0. 4 B9 is the complement of B8. 5 B0 and B1 are the reserved bits (reserved bits shall be set to 0 until defined). Table 4 Y'n:0-1 Y' channel mapping structure Bit number Word 9 8 7 6 5 4 3 2 1 0 (MSB) (LSB) B8 EP Y n:1 Y n:0 Res Res Res Res Res Res NOTES 1 MSB: most significant bit. 2 LSB: least significant bit. 3 B8 is the even parity for B7 through B0. 4 B9 is the complement of B8. 5 B0 and B1 are the reserved bits (reserved bits shall be set to 0 until defined). 4.5.4 Multiplex Structure The video data words shall be conveyed in the following order: Page 12 of 16 pages
Link A data stream: C B 0:2-11, Y 0:2-11, C R 0:2-11, Y 1:2-11, C B 2:2-11, Y 2:2-11, C R 2:2-11, Y 3:2-11 Link B data stream: A0, Y C B C R 0:0-1, A1, Y 1:0-1, A2, Y C B C R 2:0-1, A3, Y 3:0-1 See figure 9. SAMPLE NUMBER 0 1 2 3 Y':2-11 Y':2-11 Y':2-11 Y':2-11 LINK A C' B :2-11 C' B :2-11 C' R :2-11 C' R :2-11 LINK B Y'C' B C' R :0-1 Y':0-1 Y'C' B C' R :0-1 Y':0-1 Y channel A A A A C' B C' R channel Figure 9 Channel representation for Y C B C R (4:2:2) 12-bit 4.5.5 Alpha channel See 4.2.4. Page 13 of 16 pages
Y' Last Sample of Digital Active Line First Sample of Digital Active Line a C'BC'R LINK A LINK B A1918 A1919 3FF(A) XYZ(A) 3FF(A) XYZ(A) A0 A1 Y'C'BC'R1918:0-1 Y'1919:0-1 3FF(Y) 000(Y) 000(Y) XYZ(Y) 3FF(Y) 000(Y) 000(Y) XYZ(Y) Y'C'BC'R0:0-1 Y'1:0-1 C'B959:2-11 C'R959:2-11 C'B0:2-11 C'R0:2-11 Y'1918:2-11 Y'1919:2-11 3FF(Y) 000(Y) 000(Y) XYZ(Y) 3FF(Y) 000(Y) 000(Y) XYZ(Y) Y'0:2-11 Y'1:2-11 Frame/Field rate/ Pixel Depth 60 or 60/1.001 fields, 30 or 30/1.001 frames; 12-bit 50 fields, 25 frames; 12-bit 24 or 24/1.001 frames; 12-bit Total words per transmission package Total words of active image data per transmission package Word number a 2200 1920 2199 2640 1920 2639 2750 1920 2749 Figure 10 Multiplex structure Page 14 of 16 pages
5 Interface general 5.1 Signal timing considerations The timing difference between link A and link B should not exceed 40 ns at the source. This difference should be taken into consideration when designing systems and destination equipment input stages. 5.2 Link A and link B identification Link A and link B shall be identified in conformance with SMPTE 352M. Link A shall be channel 1 and link B shall be channel 2 in the SMPTE 352M (see also annex A). 5.3 Ancillary data The ancillary data shall be mapped into the blanking area of Link A and link B, and shall be in conformance with SMPTE 291M. The ancillary data mapping onto link A shall be prior to the mapping onto link B. 5.4 Audio data The audio data shall be mapped into the ancillary data space of link A and link B, and shall be in conformance with SMPTE 299M. The audio data mapping onto link A shall be prior to the mapping onto link B. Example 1: When 12 channels of audio data are mapped onto the dual link 292M, all of the 12 channels shall be mapped onto link A it is not allowed to map 8 channels onto link A and 4 channels onto link B. Example 2: When 20 channels of audio data are mapped, 16 channels shall be mapped onto link A and 4 channels shall be mapped onto link B. 5.5 Time code The time code shall be mapped into the ancillary data space of link A and link B, and shall be in conformance with SMPTE RP188. The time code mapping onto link A shall be prior to the mapping onto link B. Page 15 of 16 pages
Annex A (informative) Payload identifier definitions The payload identifier of the SMPTE 274M on dual link 292M shall be defined by SMPTE 352M. Table A.1 is the proposed payload ID of the SMPTE 274M on dual link 292M. Table A.1 (dynamic) Payload identifier definitions for 1080-line video payloads on dual link 1.485Gb/s (nominal) digital interfaces Bits Byte 1 Byte 2 Byte 3 Byte 4 Bit 7 1 Interlaced (0) or Reserved Reserved progressive (1) transport Bit 6 0 Interlaced (0) or Reserved Channel assignment of progressive (1) picture dual link Ch1 (0) or Ch2 (1) Bit 5 0 Reserved Reserved Reserved Bit 4 0 Reserved Reserved Bit 3 0 Dynamic range 100% (0 h), 200% (1 h) 400% (2 h), Reserved (3 h) Bit 2 1 Reserved Bit 1 1 Bit 0 1 Picture rate (see table 2) Sampling structure (see table 3) Bit depth 8-bit (0 h), 10-bit (1 h) 12-bit (2 h) Reserved (3 h) NOTE Table A.1 in this standard is a quotation from the table A.7 in the SMPTE 352M. Page 16 of 16 pages