Evalvid-RASV: Shaped VBR rate adaptation stored video system

摘要

Video traffic is a variable bit rates (VBR) data source in nature and it generates highly bursty traffic. Recent implementations mostly buffer the media source in order to regenerate it in the form of constant bit rates (CBR). Consequently, it will add more delays to the system and thus unable to support the original nature of the video data. Inspired by the works of Hamdi et al. [1] and Lie and Klaue [2], we developed Evalvid-RASV. This system is working on the VBR concept (open-loop video coding), but it is “shaped” so that it will not produce uncompromised bursty traffic without additional delay. With the knowledge of video characteristics in advance, Evalvid-RASV was developed to utilize the information resulting a better algorithm. In addition, we implemented the system in Evalvid-RA environment. It is an environment which is able to perform rate adaptation to the media data source and has an integrated video performance evaluation tools, especially user-perceived video quality. Our experiments have shown that Evalvid-RASV outperforms open-loop VBR in term Peak Signal Noise Ratio (PSNR) value and acceptable delay time.