From a video coding perspective, there are two challenges when performing live video distribution over error-prone networks, such as wireless networks, namely random access and packet loss repair. There is a scarceness of solutions that do not impact steady state usage and users with reliable connections. The proposed solution minimizes this impact by complementing a compression-efficient video stream with a companion stream solely consisting of keyframes.
Although the core idea is not new, this paper is the first work to provide restrictions and modifications necessary to make this idea work using the High Efficiency Video Coding (H.265/HEVC) compression standard. Additionally, through thorough quantification, insight is provided on how to provide fast channel switching capabilities and error recovery at low bitrate and quality impact, i.e. less than 10.2% average bitrate increase and less than 0.94 average VMAF score decrease. Finally, worst case drift artefacts are described and visualized such that the reader gets an overall picture of using the keyframe insertion technique.
The results presented in this study are available for download here. First, the graphs showing the VMAF / PSNR / SSIM differences of all test sequence for all configurations of keyframe insertion are given. Second, the raw aggregated result files (.csv and .xlsx) containing the VMAF / PSNR / SSIM / frame size / bitrate information are given as well.
Paper: Van Wallendael, G.; Mareen, H.; Vounckx, J.; Lambert, P. “Keyframe Insertion: Enabling Low-Latency Random Access and Packet Loss Repair.” Electronics 2021, 10, 748.