Schemes to enhance human visual perception in three-dimensional (3-D) video applications with depth map data are proposed. Depth estimation is an important part of free viewpoint television and 3-DTV because the accuracy of depth information directly affects the synthesized video quality at an intermediate viewpoint. However, generating an accurate depth map is a complex computational process that makes real-time implementation challenging. In order to obtain accurate depth information with low complexity, a depth map relabeling algorithm and a hybrid matching algorithm are proposed in the depth estimation step. These techniques in acquisition for a depth map are based on human perception, which is more sensitive to moving objects than to a static background. Also, they consider the importance of appropriate processing of object boundaries. Experimental results demonstrate that the proposed schemes provide a synthesized view with both higher subjective visual quality and better objective quality in terms of peak signal-to-noise ratio than legacy depth estimation reference software.
Dynamic quality of service (QoS) mapping control with relative service differentiation network is a futuristic framework to achieve high-quality end-to-end video streaming. The proper QoS mapping in terms of delay and loss between categorized-packet video and proportional differentiated services (DiffServ, DS) network can improve video quality under the same cost constraint. However, network congestion caused by traffic load fluctuation still remains as the main hinderance in providing persistently better service even though the resource provisioning policy of underlying network is well-established. To address this issue, we propose a class-based feedback control to enhance relative service differentiation-aware video streaming. The major idea of our proposal is to employ explicit congestion notification (ECN) mechanism in conjunction with the QoS mapping control at the ingress of a DiffServ domain. It is possible that not only the network congestion status is notified to end-host video applications but also a reactive QoS mapping control is triggeredat the ingress side. NS 2-based simulation results will be
presented to show the enhanced performance of the QoS mapping control framework.
Diverse multimedia services are at hand on 3G-and-beyond multi-service CDMA systems. Based on four different kinds of traffic types, as defined in Universal Mobile Telecommunications System (UMTS), each multimedia service needs to be admitted and allocated with appropriate resources while taking care of efficient utilization of limited resources. In this paper, we are focusing on a priority-based and QoS (quality of service)-aware CAC (call admission control), which is aware of both QoS requirement per traffic type and time-varying CDMA capability, and allows admission discrimination according to traffic types in order to minimize the probability of QoS violation. Also the CAC needs to combine resource allocation schemes such as complete sharing, complete partitioning, and priority sharing in order to provide fairness and service differentiation among traffic types. The proposed CAC adopts total received power as cell load estimation, estimates resource usage for each traffic type, and applies different threshold per each traffic type (i.e., having different SIR requirement). The performance of proposed CAC in combination with resource allocation scheme is evaluated through extensive computer simulations.