Research on an Improved QoE-based Rate-Adaptive Algorithm

Aiming at the problems of the DASH technology in the initial delay of video playback, the number and duration time which the video is buffered again and the switching frequency between different quality video, an improved QoE-based rate-adaptive switching algorithm is proposed. The algorithm reduces the initial delay of the video by using the lowest bit rate video clip as the initial play file. By designing a fast start algorithm, it can improve the video rate as soon as the current bandwidth environment is satisfied. The algorithm converts the video into multiple rate video, so that the again video buffer phenomenon will not appear when the average bandwidth of the network is greater than the minimum rate video, and the quality of the video playback can be improved in the case of the minimum initial delay, and the average quality of the video can be improved at the lowest initial delay. In order to effectively reduce the average switching times of video rate, the algorithm determines whether to switch the video rate by judging the current buffer state and the average bandwidth over a period of time. Experimental results show that the algorithm can reduce the number of again video buffering and the switching frequency between different quality video, and improved the quality of experience (QoE) of the user to DASH service.