Impact of Live Streaming WLAN Transmission Characteristics on Video Quality

In this paper, we study video quality dependence on the quality of streaming data transmission over wireless local area network. Such characteristics as packet loss rate (PLR) and packet loss distribution are used to measure the quality of video data transferring. These characteristics were measured by the specially developed program for packet loss analyzing. The video quality was evaluated by such metrics as peak signal-to-noise ratio (PSNR), structural similarity (SSIM), new quality index (NQI) and video quality metric (VQM). The experimental measurements were carried out in a real WLAN. The video server VLC was used to stream the video. The quality of wireless transmission was affected by such factors as distance, availability of access point antennas and obstacles. The video quality dependencies on packet loss rate were obtained as a result of the experimental studies. According to them, it was found that the video quality remains high when PLR<0,001, and if PLR>0,05, the video becomes impossible to perceive. The article also shows that the video quality depends on the structure of MPEG: if a lost packet belongs to intra frame, then this loss will have a greater impact than the loss of predicted or bidirectional frame.