JVET-AP0200 AHG18: Random Access GOP4 Configuration for Live-streaming Applications evaluated in ULL test conditions [S. Ikonin, I. Gribushin, M. Sychev, K. Malyshev, V. Khamidullin, B. Shevchenko, X. Ma, E. Alshina (Huawei), Z. Deng (Bytedance)]

This contribution reports evaluation results of random access GOP4 configuration suggested by contribution JVET-AM0238 in low latency scenario. Under ULL test conditions described in JVET-AN2039 with latency restriction modified to the range of 70 to 130 ms it was observed that temporal layer 0 is delivered in most of the cases confirming the benefits of temporal scalability in low latency scenario. At the same time temporal layers 1 and 2 are often missed due to network transmission issues leading to instant FPS drop clearly noticeable during video playback. The ULL CfE response published as contribution JVET-AN0080 was also evaluated in the same conditions, and at QP22 demonstrated 2.1 dB of average Y-PSNR improvement, and 28% to 16% of freeze ratio reduction for transmission priority channel, and 0.8 dB average Y-PSNR improvement and 31% to 27% freeze ratio reduction on a channel without transmission priorities, with 1.9% BD-Rate overhead of Y-PSNR. The modifications required for evaluation of RA configuration on top of AHG18 simulation software are also described.

It was agreed to include this as an option for further study into the AHG software.

It was commented that this is not “ultra” low latency, unlike the other scenarios/configurations investigated so far, but a higher variety of cases is probably welcome.