1、 Copyright 2009 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved May 29, 2009 Document renumbered July 21, 2010 Table of Contents Page Foreword . 2 Intellectual Property 2 1 Scope 3 2 Conformance Notation 3 3 Normative Referenc
2、es 4 4 Definition of Terms 4 5 Overview . 6 6 Audio Data Packet 9 7 Audio Control Packet 19 Annex A Recommendations for Handling of SMPTE 337 Non-PCM Data (Informative) 25 Annex B Recommendations for Handling Legacy Implementations (Informative) 26 Annex C Bibliography (Informative) . 27 Annex D Add
3、itional Sampling Frequency (Informative) . 28 Page 1 of 28 pages SMPTE ST 299-1:2009 Revision of SMPTE 299M-2004 NOTE: This document previously numbered SMPTE 299-2009; Content Unchanged SMPTE STANDARD 24-Bit Digital Audio Format for SMPTE 292 Bit-Serial Interface SMPTE ST 299-1:2009 Page 2 of 28 pa
4、ges 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 six continents. SMPTEs Engineering Documents, incl
5、uding 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-developing organizations, including ISO, IEC and IT
6、U. SMPTE Engineering Documents are drafted in accordance with the rules given in Part XIII of its Administrative Practices. SMPTE Standard 299-1 was prepared by Technology Committee 32NF. Intellectual Property SMPTE draws attention to the fact that it is claimed that compliance with this Standard ma
7、y involve the use of one or more patents or other intellectual property rights (collectively, “IPR“). The Society takes no position concerning the evidence, validity, or scope of this IPR. Each holder of claimed IPR has assured the Society that it is willing to License all IPR it owns, and any third
8、 party IPR it has the right to sublicense, that is essential to the implementation of this Standard to those (Members and non-Members alike) desiring to implement this Standard under reasonable terms and conditions, demonstrably free of discrimination. Each holder of claimed IPR has filed a statemen
9、t to such effect with SMPTE. Information may be obtained from the Director, Standards or that a certain course of action is preferred 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
10、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. The keyword “forbidden” indicates “reserved” and in addition indicates that the provision
11、 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“) as described. A conformant implementation need not implement optional provisions (“may“) and
12、 need not implement them as described. SMPTE ST 299-1:2009 Page 4 of 28 pages 3 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards
13、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. AES3-2003, AES Standard for Digital Audio Digital Input-Output Interfacing Serial Transmission Format for Two-
14、Channel Linearly Represented Digital Audio Data (AES3) SMPTE 291M-2006, Television Ancillary Data Packet and Space Formatting SMPTE 292-2008, 1.5 Gb/s Signal/Data Serial Interface SMPTE RP 168-2002, Definition of Vertical Interval Switching Point for Synchronous Video Switching 4 Definition of Terms
15、 4.1 AES audio: All the VUCP (sample validity bit (V), channel status bit (C), user data bit (U), even parity bit (P) data, audio data and auxiliary data, associated with one AES digital stream as defined in AES3. 4.2 AES frame: Two AES subframes: in the case of the 32 kHz to 48 kHz sampling subfram
16、es, one and two carry AES audio channel 1 and 2, respectively. In the case of 96 kHz sampling subframes, one and two carry successive samples of the same AES audio signal which is mandatory for 96 kHz application. 4.3 AES subframe: All data associated with one AES audio sample for one channel in a c
17、hannel pair. 4.4 Ancillary data packet: A data packet as defined by SMPTE 291M. 4.5 audio clock phase data: Audio clock phase is indicated by the number of video clocks between the first word of EAV and the video sample appearing at the same time as the audio sample at the input to the formatter. 4.
18、6 audio control packet: An ancillary data packet occurring once a field in an interlaced system and once a frame in a progressive system and containing data used in the process of decoding the audio data stream. 4.7 audio data: 29 bits: 24 bits of AES audio associated with one audio sample, includin
19、g AES auxiliary data, plus VUCP bits and the Z flag which is derived from the preamble of AES3 stream. The Z bit is common to the two channels of an AES channel pair. 4.8 audio data packet: An ancillary data packet containing audio clock phase data, audio data for 2 channel pairs (4 channels) and er
20、ror correction code. An audio data packet shall contain audio data of one sample associated with each audio channel. 4.9 audio frame number: A number, starting at 1, for each frame within the audio frame sequence. For the example in 4.9, 48 kHz sampling at 30.00/1.001 frames/s system, the frame numb
21、ers would be 1, 2, 3, 4 and 5. 4.10 audio frame sequence: The number of video frames required for an integer number of audio samples in synchronous operation. As an example, the audio frame sequence for synchronous 48 kHz sampling at 30.00/1.001 frames/s system is 5 frames. 4.11 audio group: Consist
22、s of two channel pairs that are contained in one ancillary data packet. Each audio group has a unique ID as defined in 6.1 and 7.1. Audio groups are numbered 1 through 4. SMPTE ST 299-1:2009 Page 5 of 28 pages 4.12 auxiliary data: Four bits of data associated with one AES audio sample defined as aux
23、iliary data by AES3. The four bits can be used to extend the resolution of the audio sample. 4.13 channel pair: Two digital audio channels, derived from the same AES audio source. 4.14 data ID: A word in the ancillary data packet that identifies the use of the data therein. 4.15 error correction cod
24、e: BCH (31, 25) code (an error-correction method) in each bit sequence of b0-b7. Errors between the first word of ancillary data flag (ADF) through the last word of audio data of channel 4 (CH4) in user data words (UDW) can be corrected or detected within the capability of this code. 4.16 horizontal
25、 ancillary data block: An ancillary data space located in the digital line blanking interval of one television line. 4.17 synchronous audio: Audio is defined as being clock synchronous with video if the sampling rate of audio is such that the number of audio samples occurring within an integer numbe
26、r of video frames is itself a constant integer number. Examples are shown in Table 1. Table 1 Examples of audio samples per frame for synchronous audio Samples/frame Audio sampling rate 30.00 frame/s 30.00/1.001 frame/s 25.00 frames/s 24.00 frames/s 24.00/1.001 frames/s 96.0 kHz 3200/1 16016/5 3840/
27、1 4000/1 4004/1 48.0 kHz 1600/1 8008/5 1920/1 2000/1 2002/1 44.1 kHz 1470/1 147147/100 1764/1 3675/2 147147/80 32.0 kHz 3200/3 16016/15 1280/1 4000/3 4004/3 AES11 provides specific recommendations for audio and video synchronization. Note: Implementations of this standard may achieve synchronous or
28、asynchronous operation through the use of sample rate converters. In the context of this standard, synchronous audio applies to the AES audio stream that is directly mapped into the ancillary data space, which may or may not be the AES audio stream present on device interfaces. It is recommended tha
29、t product manufacturers clearly state when sample rate conversion is used to support multiple sample rates and/or asynchronous operation. It is also recommended that the use of sample rate conversion be user selectable. For example, when the AES audio data contains SMPTE 337 formatted data the use o
30、f sample rate conversion will corrupt the SMPTE 337 data (see Annex A). This recommendation applies to both multiplexing (embedding) and demultiplexing (receiving) devices. SMPTE ST 299-1:2009 Page 6 of 28 pages 5 Overview 5.1 The modes of transmission carried in an audio data packet defined in 6 sh
31、all be the TWO-CHANNEL MODE at all sampling frequencies from 32 kHz to 48 kHz, and the SINGLE CHANNEL DOUBLE SAMPLING FREQUENCY MODE at the sampling frequency of 96 kHz as defined in AES3. Audio data channels 14 (CH1 CH4) defined in 6.2.2 carry two AES audio channel pairs (AES1 channel 1 and 2 and A
32、ES2 channel 1 and 2) in the case of 32 kHz to 48 kHz sampling. For 96 kHz sampling, two successive samples of two AES audio channels (AES1 channel 1 1stand 2ndsample and AES2 channel 1 1stand 2ndsample) shall be carried. Note: AES3 document allows for different audio samples configurations of the di
33、gital audio. Single sample mode or successive sample modes are permitted in AES3 without regard to used sampling frequency. 5.2 The 32 kHz, 44.1 kHz or 48 kHz sampling audio data derived from two channel pairs shall be configured in an audio data packet as shown in Figure 1. Both channels of a chann
34、el pair are derived from the same AES audio source. The number of samples per channel used for one audio data packet shall be constant and is equal to one. The number of audio data packets in a given group shall be less than or equal to Na in a horizontal ancillary data block. The definition and exa
35、mples of Na are described in 6.3.3. 5.3 Figure 2 shows the audio data packet at the sampling rate of 96 kHz. AES subframes 1 and 2 carry successive samples of the same AES audio signal. Both channels shall be derived from the same AES audio source. The number of samples per channel used for one audi
36、o data packet shall be constant and equal to two. The number of audio data packets in a given group is less than or equal to Na/2 in a horizontal ancillary data block. The definition and examples of Na are described in 6.3.3. 5.4 Two types of ancillary data packets carrying AES audio information are
37、 defined and formatted per SMPTE 292. Each audio data packet shall carry all of the information in the AES bit stream as defined by AES3. The audio data packet shall be located in the horizontal ancillary data space of the Cb/Crdata stream. An audio control packet shall be transmitted once per field
38、 in an interlaced system and once per frame in a progressive system in the horizontal ancillary data space of the second line after the switching point of the Y data stream. 5.5 Data ID shall be defined for four separate packets of each packet type. This allows for up to eight channel pairs. In this
39、 standard, the audio groups are numbered 1 through 4 and the channels are numbered 1 through 16. Channels 1 through 4 are in group 1, channels 5 through 8 are in group 2, and so on. Table 2 defines the relationship between CH1CH4 (UDW2UDW17) in the audio data packet and the channel/sample number for
40、 32 kHz to 48 kHz sampling and 96-kHz sampling respectively. 5.6 The audio data packet and audio control packet shall be located in SMPTE 292 transport HANC space that is equal to 268 clock pulses at 30 Hz video frame rate. SMPTE ST 299-1:2009 Page 7 of 28 pages Y channel 2 Z Y Xchannel 1 channel 2
41、channel 1 Y channel 2AESchannel pair 2(AES2)AESsubframe 2AESsubframe 1AESsubframe 2AESsubframe 1AESsubframe 2AES frame 191 AES frame 0 AES frame 1Y channel 2 Z Y Xchannel 1 channel 2 channel 1 Y channel 2AESchannel pair 1(AES1)AESsubframe 2AESsubframe 1AESsubframe 2AESsubframe 1AESsubframe 2AES fram
42、e 191 AES frame 0 AES frame 1Preamble4-bitAES1channel 1(CH1)AES channel pair 1, subframe 2(CH2)Audio data 20-bitV U C PAES subframe 32-bitADF DID DBN DC CLKAUX dataorAudio data4-bitAES1channel 2(CH2)AES2channel 1(CH3)AES2channel 2(CH4)ECC 0ECC 1ECC 2ECC 3ECC 4ECC 5CSA sample of AES audio data istran
43、sferred to 4 words in an audio data packet3 1 1 1 2 4 4 4 4 6 1Number of wordsFigure 1 Relationship between AES audio and audio data packets at sampling rates of 32 kHz, 44.1 kHz or 48 kHz SMPTE ST 299-1:2009 Page 8 of 28 pages Y channel 1 Z Y Xchannel 11st samplechannel 12nd samplechannel 1 Y chann
44、el 1AES2nd channel(AES2)AESsubframe 2AESsubframe 1AESsubframe 2AESsubframe 1AESsubframe 2AES frame 191 AES frame 0 AES frame 1Y channel 1 Z Y Xchannel 11st samplechannel 12nd samplechannel 1 Y channel 1AES1st channel(AES1)AESsubframe 2AESsubframe 1AESsubframe 2AESsubframe 1AESsubframe 2AES frame 191
45、 AES frame 0 AES frame 1Preamble4-bitAES1channel 11st sample(CH1)AES channel 1, subframe 2Audio data 20-bitV U C PAES subframe 32-bitADF DID DBN DC CLKAUX dataorAudio data4-bitAES1channel 12nd sample(CH2)AES2channel 11st sample(CH3)AES2channel 12nd sample(CH4)ECC 0ECC 1ECC 2ECC 3ECC 4ECC 5CSA sample
46、 of AES audio data istransferred to 4 words in an audio data packet3 1 1 1 2 4 4 4 4 6 1Number of wordsFigure 2 Relationship between AES audio and audio data packets at a sampling rate of 96 kHz SMPTE ST 299-1:2009 Page 9 of 28 pages Table 2 Relationship between audio data packets and the channel/sa
47、mple number of 32 kHz to 48 kHz and 96 kHz sampling Audio Group 132.0 kHz, 44.1 kHz or 48.0 kHz96.0 kHzUDW2UDW5CH1UDW6UDW9CH2UDW10UDW13CH3UDW14UDW17CH4AES1channel 1AES1channel 2AES1channel 11st sampleAES2channel 1AES2channel 2AES1channel 12nd sampleAES2channel 11st sampleAES2channel 12nd sampleAudio
48、 sampling rate6 Audio Data Packet 6.1 Structure of Audio Data Packet 6.1.1 The structure of the audio data packet shall be as shown in Figure 3. Audio data packets shall be formatted according to the requirements of SMPTE 291M and shall include ancillary data flag (ADF), data identification (DID), d
49、ata block number (DBN), data count (DC), user data words (UDW) and checksum (CS) fields as specified in SMPTE 291M. DC is always 218h. AES1channel 1ADF DID DBN DC CLKAES1channel 2AES2channel 1AES2channel 2ECC 0ECC 1ECC 2ECC 3ECC 4ECC 5CS3 1 1 1 2 4 4 4 4 6 1Number of wordsECC protectedUDW0UDW1UDW2UDW3UDW4UDW5UDW6UDW7UDW8UDW9UDW10UDW11UDW12UDW13UDW14UDW15UDW16UDW17UDW18UDW19UDW20UDW21UDW22UDW23AES1channel 11st sampleAES1channel 12nd sampleAES2channel 11st sampleAES2channel 12nd sample32 kHz to 48 kHz sampling audio96 kHz sampling au
