Receiver error concealment using acknowledge preview (RECAP) - An approach to resilient video streaming

High-quality and low-latency video streaming is essential to providing a natural user experience in video conferencing. This is challenging over lossy networks since compressed video is highly fragile while the low-latency requirement limits the effectiveness of traditional error control approaches such as retransmission and forward error correction. In this paper, we advocate a practical solution for low-latency video communications over best-effort networks that employs an additional low-quality, low-resolution but robustly coded copy of the video. This approach, called RECAP, incurs minimal rate overhead, and can be combined with previously decoded frames to achieve effective concealment of isolated and burst losses even under tight delay constraints. RECAP achieves PSNR gains of 2-6 dB against complete frame loss.