Domenico Striccoli

3D Video transmissions over LTE: A performance evaluation

The emerging broadband cellular technology, i.e. the Long Term Evolution (LTE), aims to support different services with high data rates and strict Quality of Service (QoS) requirements. It can thus be considered a very promising architecture for the three-dimensional (3D) video transmission. Differently from the conventional 2D video, the depth perception is the most important aspect characterizing 3D streams. It significantly influences the mobile users Quality of Experience (QoE). However, it requires the transmission of additional information as well as more bandwidth and a lower loss probability. The goal of this paper is to investigate how both 3D video formats and their average encoding rate impact on the quality experienced by the end users when the video flow is delivered through the LTE network. To this aim, objective metrics like the ratio of lost packets, Peak Signal to Noise Ratio, delay, and goodput are adopted for measuring QoS and QoE degrees. At the end of this analysis, we provide some important considerations about the LTE effectiveness for 3D video delivering.

A smoothing algorithm for time slicing DVB-H video transmission with bandwidth constraints

DVB-H transmission is assuming an ever growing importance for multimedia data delivery to hand-held terminals of reduced size and limited battery capacities. To minimize terminals power consumption, DVB-H systems adopt a time sliced transmission in bursts. In such a context, in this paper a new smoothing algorithm, the Smoothing Algorithm of the Burst (SAB), suitable for the transmission of multimedia streams with high bit rate variability, has been proposed and analyzed. Such an algorithm takes into account receiving buffer size, burst size and available bandwidth variability to reschedule data transmission, with the target to minimize the percentage of loss due to bandwidth and buffer limitations. Numerical results obtained by simulation show the improved performance of SAB compared with the usual unsmoothed data transmission in bursts. SAB can thus be utilized to transmit video streams with higher bit rate and better quality than actually considered in DVB-H systems.

An Energy Efficient and Reliable Composite Metric for RPL Organized Networks

In the recent past, we witnessed to a dramatic growth of networks with a huge number of interconnected wireless nodes exchanging large amounts of information. This has brought to the need of ad-hoc, energy-aware protocols suitable for low-power and lossy networks. Among these, Routing Protocol for Low Power and Lossy Networks (RPL) is surely one of the most interesting ones. It chooses the optimal routes from a source to a destination node, based on specific metrics. In this work we present a RPL compliant composite metric that considers both reliability and energy. Its aim is twofold. First, it realizes energy consumption balancing, so that each node tends to consume the same amount of energy of all the others, thus prolonging the overall network lifetime. Second, it takes into account data reliability along the paths, expressed by the well known Expected Transmission Count (ETX). The effectiveness of the proposed metric is confirmed by some interesting simulation results, that strongly encourage a deeper investigation on this issue.

Queueing networks approach for bandwidth estimation of smoothed VBR video streams

The growing importance of multimedia applications, which usually implies the transmission of variable bit rate (VBR) video streams, needs an accurate analysis of bandwidth requirements according to specified quality of service (QoS) guarantees. In this paper an original algorithm is proposed for statistical aggregate bandwidth estimation of smoothed VBR video streams, respecting a specified loss probability (the QoS parameter taken into account). This algorithm is based on concepts of multiclass networks of queues whose service centers are represented by the bandwidth levels assumed by smoothed films. The mean service times and the transition probabilities between service centers are directly derived from real video traces. The analytical results have been compared with simulation results and with the results obtained by another analytical method already present in the literature, i.e., the Chernoff bound, discussing the effectiveness of the proposed method.

Periodic Feedback Control for Streaming 3D Videos in Last-Generation Cellular Networks

Abstract Transmitting stereoscopic 3D videos on cellular networks is a challenging issue because effective scheduling is necessary for reproducing frames continuously, without wasting bandwidth in frame retransmissions. We propose a scheduling algorithm that allows the user of interactive videos to perform VCR-like actions other than the usual playback (e.g., pause or fast forward at different speeds) with less problems. The algorithm exploits periodic feedback packets coming from the client to the server through the Real-time Transport Control Protocol and communicating the client buffer fill level. A P-controller uses this information to dynamically regulate the scheduled bitrate. The approach is compared with classical scheduling algorithms. Different 3D video formats and quality degrees are considered. Results show that the simple controller is very effective and outperforms the other schedulers in all the analyzed scenarios.

Performance evaluation of 3D video streaming services in LTE-Advanced networks

Abstract Due to the ever growing interest of 3-dimensional (3D) technology, together with the the widespread use of new generation smartphones, netbooks, and tablets, the idea to provide 3D multimedia services also to mobile users is attracting the attention of researchers worldwide. The emerging long term evolution-advanced (LTE-A) technology seems to have all the potential to offer such kind of services but no accurate studies have been yet conducted to demonstrate this assumption. To bridge this gap, we investigate herein how the LTE-A network configuration, the traffic load, and 3D video settings may influence to the quality of all services of all active flows. We consider a heterogeneous LTE-A network composed by macro and pico cells and a number of users uniformly distributed into the scenario, that receive at the same time 3D video streams, voice flows and best-effort applications. Moreover, several objective metrics, such as the ratio of lost packets, the peak signal to noise ratio, the Structural SIMilarity, the application goodput, and packet delays, have been evaluated to show the LTE-A effectiveness in delivering 3D videos in a realistic last generation mobile environment.

A scheduling algorithm for interactive video streaming in UMTS networks

The importance of a Variable Bit Rate (VBR) video transmission on UMTS networks is increasing in time. The bursty nature of VBR traffic complicates the design of efficient mechanisms for video retrieval, transport, and provisioning to achieve a high bandwidth utilization and reduce the negative effects of bandwidth fluctuations in wireless channels. To this aim, several scheduling algorithms can be successfully implemented. They regulate data transmission to reduce the rate variability peculiar of VBR streams. At client side, scheduled data are temporarily stored in the client buffer before being decoded on the terminal. In this work, a novel scheduling algorithm, the Scheduling Algorithm for Interactive Video (SAIV) is presented and analyzed. It is an algorithm thought for VBR stream transmission in UMTS networks that takes into account the user interactivity. Scheduling is performed “online”, over relatively small video segments to reduce delays. SAIV dynamically varies the sampling frequency of the Real Time Control Protocol (RTCP) feedbacks that carry information on the client buffer status. The sampling frequency is modulated according to the difference between the calculated buffer fill level at server side and the real buffer fill level at client side. The latter is exploited to reschedule data with the updated information. Numerical results testify the SAIV effectiveness compared to the classical SLWIN online algorithm already known by literature, in some simulation scenarios of real interest.

A bandwidth dependent window-based smoothing algorithm for wireless video streaming in UMTS networks

Variable Bit Rate (VBR) video transmission over UMTS networks is assuming an ever growing importance. To face the problem of VBR data transmission over wireless channels, work-ahead smoothing techniques can be fruitfully adopted. In this work, a sliding window smoothing algorithm, particularly suitable for real-time interactive multimedia transmission of VBR streams is proposed. It smoothes video streams over partially overlapped time windows, taking into account the fluctuating available bandwidth profile, typical of the wireless link, and the feedback on the real available buffer size periodically coming from client terminals, with the aim to minimize losses. Numerical results demonstrate the effectiveness of the proposed algorithm if compared with the sliding version of Minimum Variability Bandwidth Allocation (MVBA) algorithm, already known by literature, in different contexts.

Bandwidth estimation in prerecorded VBR-video distribution systems exploiting stream correlation

The main aspect of several multimedia applications is the transmission of variable bit rate (VBR) video streams requiring high bandwidth with stringent quality of service (QoS) guarantee. In such systems, a statistical bandwidth estimation is relevant for network infrastructure planning and admission control. In this paper, an original algorithm for aggregate bandwidth estimation, needed by a given number of correlated video streams, is proposed and analyzed. The obtained analytical results are validated by simulation and compared with other numerical results already present in the literature, discussing the effectiveness of the proposed solution.

Aggregate bandwidth estimation in stored video distribution systems

Multimedia applications like video on demand, distance learning, internet video broadcast, etc. will play a fundamental role in future broadband networks. A common aspect of such applications is the transmission of video streams that require a sustained relatively high bandwidth with stringent requirements of quality of service. In this paper various original algorithms for evaluating, in a video distribution system, a statistical estimation of aggregate bandwidth needed by a given number of smoothed video streams are proposed and discussed. The variable bit rate traffic generated by each video stream is characterized by its marginal distribution and by conditional probabilities between rates of temporary closed streams. The developed iterative algorithms evaluate an upper and lower bound of needed bandwidth for guaranteeing a given loss probability. The obtained results are compared with simulations and with other results, based on similar assumptions, already presented in the literature. Some considerations on the developed algorithms are made, in order to evaluate the effectiveness of the proposed methods. Copyright