GB/T 39274-2020 in English

As a supporting test specification for GB/T 25724-2017, this standard specifies the technical test framework for video encoders, video decoders, audio encoders and audio decoders in public security video surveillance systems. The encoding and decoding quality of networked sharing systems is ensured through a unified test method.

Monitoring extended information encoding must contain an absolute time identifier (extension_id=4), and the time synchronization accuracy must be verified during the test. For video encoding chips, Appendix A specifically stipulates that 12Mbps high bit rate performance must be tested at 3840×2160@30fps.

ROI function test requires that segmentation_enable=1 and roi_flag=1 exist in the encoded stream at the same time, and the QP value difference of each ROI area must be ≥5.

1. Test environment construction: It is recommended to configure a standard test source library, including 10 typical monitoring scenarios (such as low illumination at night, high-speed motion, etc.)

2. Automated testing: Develop a test tool chain that meets the requirements of Chapter 4 of the standard, supporting automatic parsing of syntax elements and generation of BD-Rate curves

3. Chip-level verification: For video encoding chips, it is necessary to add -20℃~70℃ temperature cycle tests to verify the stability of encoding and decoding