2019, Contributo in atti di convegno, ENG
Bacco M.; Catena M.; de Cola T.; Gotta A.; Tonellotto N.
This work analyses the use of the Web Real-Time Communications (WebRTC) framework on resource-constrained platforms. WebRTC is a consolidated solution for real-time video streaming, and it is an appealing solution in a wide range of application scenarios. We focus our attention on those in which power consumption, size and weight are of paramount importance because of the so-called Size, Weight and Power (SWaP) requirements, such as the use case of Unmanned Aerial Vehicles (UAVs) delivering real-time video streams over WebRTC to peers on the ground. The testbed described in this work shows that the power consumption can be reduced by changing WebRTC default settings while maintaining comparable video quality.
2009, Contributo in atti di convegno, ENG
Ferro E.; Gotta A.; Potortì F.
In case of video streaming services via satellite towards vehicular clients, very long blockage periods due to road infrastructures, vegetation, and so on, may lead to a complete channel outage, which may result in the loss of all packets transmitted during that period, even in the presence of interleaving and FEC techniques. But if these periods are predictable, as in the presence of known routes traced by means of a GPS navigator, it may be advisable to alert the transmitter in advance, in order to counteract the incoming outage interval. We refer to this technique as Smart Mode. In the following we will detail how Smart Mode takes advantage of FEC and interleaving techniques, in order to improve the Quality of Experience and to reduce the waste of bandwidth in satellite multimedia streaming.
2009, Contributo in atti di convegno, ENG
Pradas D.; Barsocchi P.; Jiang L.; Potortì F.; Vazquez Castro M. A.
This paper aims at providing different cost-efficient solutions for the channel impairments in tropical areas. In order to extend service to isolated areas, we propose an hybrid architecture based on DVB-S2/RCS + Wi-Fi networks. In this scenario, the delay of the ACM reaction to fade changes can affect the quality of the video transmission, especially because of the characteristics of tropical deep fading events. In order to avoid QoS reduction, we focus on the DVB PHY-layer shifted threshold, which we study not only for different Amazon areas and different rain conditions, but also for different reaction delays. The performance of the PHY-layer selector is evaluated in terms of video quality (PSNR), packet error rate and bandwidth efficiency.