Real-time services for video communications

Time-sensitive nature of video communications necessitates the employment of network services which operate in real-time. Such services are required for the personalisation of multimedia content and efficient use of network resources. This paper presents the performance and characteristics of a series of video transcoding services, which are rate-control (RC), adaptive data-partitioning (DP), video packet resynchronisation (VPR), adaptive intra refresh (AIR), and application-layer multicast (ALM). These have been designed by considering the trade-off between the operational-performance and perceptual quality. Simulations have revealed that the perceptual quality of the video content can effectively be adapted in real-time to meet the user requirements.