Pick your Layers wisely - A Quality Assessment of H.264 Scalable Video Coding for Mobile Devices

摘要

Multi-dimensional video scalability as defined in H.264/SVC is a promising concept to efficiently adapt encoded streams to individual device capabilities and network conditions. However, we still lack a thorough understanding of how to automate scaling procedure in order to achieve an optimal quality of experience (QoE) for end uses. In this paper we present and discuss the results of a subjective quality assessment we performed on mobile devices to investigate the effects of multi-dimensional scalability on human quality perception. Our study reveals that QoE degrades non-monotonically with bitrate and that scaling order preferences are content-dependent. We confirm previous studies which found common objective metrics to fail for scalable content, but we also show that even scalability-aware models perform poor. Our results are supposed to help improving the design of quality metrics and adaptive network services for scalable streaming applications.