GY/T 313-2017 in English

GY/T 313-2017, jointly developed by China Central Television and other authoritative organizations, specifies the technical specifications for the entire HDTV production process, from acquisition to final production. This standard, which inherits and develops from earlier standards such as GY/T 155, adapts to the evolution of 4K UHD, focusing on addressing issues such as recording device compatibility and program exchange standardization.

The standard explicitly requires the use of 4:2:2 sampling, intra-frame compression bitrate ≥100Mbps, and inter-frame compression bitrate ≥50Mbps. It specifically stipulates that the image safe zone must comply with GY/T 272-2013, and technical defects such as full-frame black (brightness <18/72) and monochrome images (color difference <10/40) are prohibited.

Typical Violation Cases

• A certain satellite TV variety show used an uncalibrated camera, resulting in a purple skin tone.
• An early version of the documentary "Natural China" had a 0.5% area Y signal exceeding the standard.

The audio standard highlights loudness control (-24LKFS±2LU) and channel management:

1. Stereo programs must be marked with a channel identification signal (1kHz sine wave)
2. Surround sound programs provide 8/16-channel distribution options
3. True peak level is strictly limited to ≤-2dB TP

Channel Allocation Example

Track 1 - Program Left Channel| Track 3 - International Left Channel | Track 2 - Program Right Channel | Track 4 - International Right Channel

Equipment Selection

Prioritize recording and editing equipment that supports the GY/T 157-2000 digital interface to ensure frame-accurate editing capabilities.

Quality Control

• Establish a color bar signal calibration process
• Use a professional loudness meter to monitor LKFS values
• Implement two-person verification of metadata

File Management

Segment program files according to standard requirements (≤1 hour/file). MXF packaging format (SMPTE ST 377-1) is recommended.