Enhancement of QoE in Audio-Video IP Transmission by Utilizing Tradeoff between Spatial and Temporal Quality for Video Packet Loss

This paper proposes a methodology of video-stream output at the receiver for enhancing QoE (Quality of Experience) in audio-video IP transmission. The methodology copes with video packet loss by error concealment and/or video frame skipping; it utilizes the tradeoff relation of QoE between spatial and temporal quality caused by the two techniques. As a simple example of the methodology, we adopt a scheme which switches between the two techniques according to the percentage of video slices error-concealed in a frame; the scheme is referred to as SCS (Switching between error Concealment and frame Skipping). We conducted experiments on the SCS with six contents. Taking into consideration the cross-modal interaction between audio and video, we then assessed QoE in terms of the psychological scale, which is more accurate than MOS (Mean Opinion Score). The experimental result shows that the SCS can improve QoE over the simple error concealment or frame skipping by selecting an appropriate threshold value of the error concealment ratio, which depends on the content type, video picture pattern and degree of video motion.