Unequal Error Protection for Scalable Video Storage in the Cloud
Redundancy is necessary for a storage system to achieve reliability. Frequent errors in large-scale storage systems, for example, cloud, make it desirable to reduce the cost of recovery. Among all types of data in cloud storage, videos generally occupy significant amounts of space due to high volumes and the rapid development of video sharing and video-on-demand services. Unlike general data, videos can tolerate a certain level of quality degradation. This paper investigates multilayer video representations, such as scalable videos and simulcast streaming, and proposes an unequal error protection scheme based on local reconstruction codes (LRC) for video storage. By providing less protection for less important layers or video copies, a better tradeoff between storage and repair cost is achieved. Both theoretical and simulation results show that such a tradeoff can be achieved over the LRC with equal error protection, though the recovered video quality might be slightly lower in rare cases.