This standard is formulated in accordance with the International Telecommunication Union's ITU-R BS.647-2 Recommendation "Digital Audio Interface for Broadcasting Studios". This international standard is widely adopted in the field of digital broadcasting and television (including digital high-definition television). This standard specifies the signal format for a studio digital audio signal interface using periodic sampling and linear quantization for dual channel serial digital transmission, which includes clock reference and auxiliary data transmitted together with audio program signals. This standard also specifies the level of signal format execution. In the studio, various digital audio devices need to be interconnected within the digital domain, including digital recorders, audio systems for digital video recorders, mixing stations, etc. When using cables to connect different TV devices to transmit digital audio signals, there are two types of physical interfaces. The first is to use balanced twisted pair cables to transmit signals. The cable connector is an XLR type, described in ITU-R BS.647-2 Recommendation; The second method is to use coaxial cables for unbalanced signal transmission, and the cable connectors are BNC type, as recommended by SMPTE 276M. Regardless of the type of interface used, the content of the transmitted digital audio signal (including audio sampling signal, timing synchronization signal, auxiliary signal, and user data) and source coding method (GB/T 14919-1994 "Technical Specification for Source Coding of Digital Sound Signals") are the same. Therefore, after determining the signal format of the interface, this standard specifies the electrical parameters, mechanical connection methods, and matching networks for the electrical connections of the two physical interfaces. The signal format of digital audio specified in this standard can be embedded into digital video signals through multi-channel combination to achieve the sound transmission interface requirements of high-definition television. The embedding specifications should comply with the provisions of GY/T 161-2000 "Transmission Specifications for Digital Audio and Auxiliary Data in the Digital Television Satellite Data Space"
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