Power Efficient Mobile VTuber Live Streaming.

Virtual YouTuber (VTuber) live streaming, which renders and streams a virtual avatar of the real-person streamer on top of the live camera view, has gained significant popularity recently. Despite the engaging user experience, the intensive and power-consuming computations required by VTuber, such as facial feature extraction and avatar rendering, pose significant challenges to the constrained battery life of the mobile device. We develop a power efficient VTuber live streaming system by offloading the camera view and the computation-intensive operations from the mobile device to an edge server, which not only significantly reduces the power consumption of the mobile device but also enables larger-scale rendering of multiple avatars that are not feasible in the existing mobile VTuber systems. Furthermore, to reduce the bandwidth overhead caused by the camera view offloading, we develop an adaptive framerate control mechanism to dynamically adjust the framerate of the offloaded camera view based on the variations of inter-frame luminance. Our evaluations on the end-to-end VTuber live streaming system demonstrate significant power savings with limited bandwidth, latency, and quality overhead.