60,062 research outputs found
Acceptance and usage of webcasting among users of selected cyber cafes in Klang Valley
The Malaysian public now has access to the Internet not only at home and the workplace, but also at cyber cafés. This study aims to examine the level of acceptance of webcasting among users of selected cyber cafés in the Klang Valley. The specific objectives of the study are: to determine the profile of webcasting users and its usage; to determine the types of webcasting technology most frequently used, level of knowledge of webcasting and the main source of knowledge in becoming aware of webcasting; to determine the acceptance of webcasting among non-users of webcasting; and to determine the relationship between behavioral intention to use and the actual usage of webcasting among users of webcasting. This study used the survey design, using purposive sampling to select the cyber cafés and visitors of these cafés. The findings indicate that usage of webcasting is still relatively low among users of selected cyber cafés in the Klang Valley. Users of webcasting were found to be mostly male, young and relatively well educated with at least a diploma as the highest level of education obtained
QoE-Based Low-Delay Live Streaming Using Throughput Predictions
Recently, HTTP-based adaptive streaming has become the de facto standard for
video streaming over the Internet. It allows clients to dynamically adapt media
characteristics to network conditions in order to ensure a high quality of
experience, that is, minimize playback interruptions, while maximizing video
quality at a reasonable level of quality changes. In the case of live
streaming, this task becomes particularly challenging due to the latency
constraints. The challenge further increases if a client uses a wireless
network, where the throughput is subject to considerable fluctuations.
Consequently, live streams often exhibit latencies of up to 30 seconds. In the
present work, we introduce an adaptation algorithm for HTTP-based live
streaming called LOLYPOP (Low-Latency Prediction-Based Adaptation) that is
designed to operate with a transport latency of few seconds. To reach this
goal, LOLYPOP leverages TCP throughput predictions on multiple time scales,
from 1 to 10 seconds, along with an estimate of the prediction error
distribution. In addition to satisfying the latency constraint, the algorithm
heuristically maximizes the quality of experience by maximizing the average
video quality as a function of the number of skipped segments and quality
transitions. In order to select an efficient prediction method, we studied the
performance of several time series prediction methods in IEEE 802.11 wireless
access networks. We evaluated LOLYPOP under a large set of experimental
conditions limiting the transport latency to 3 seconds, against a
state-of-the-art adaptation algorithm from the literature, called FESTIVE. We
observed that the average video quality is by up to a factor of 3 higher than
with FESTIVE. We also observed that LOLYPOP is able to reach a broader region
in the quality of experience space, and thus it is better adjustable to the
user profile or service provider requirements.Comment: Technical Report TKN-16-001, Telecommunication Networks Group,
Technische Universitaet Berlin. This TR updated TR TKN-15-00
Online multipath convolutional coding for real-time transmission
Most of multipath multimedia streaming proposals use Forward Error Correction
(FEC) approach to protect from packet losses. However, FEC does not sustain
well burst of losses even when packets from a given FEC block are spread over
multiple paths. In this article, we propose an online multipath convolutional
coding for real-time multipath streaming based on an on-the-fly coding scheme
called Tetrys. We evaluate the benefits brought out by this coding scheme
inside an existing FEC multipath load splitting proposal known as Encoded
Multipath Streaming (EMS). We demonstrate that Tetrys consistently outperforms
FEC in both uniform and burst losses with EMS scheme. We also propose a
modification of the standard EMS algorithm that greatly improves the
performance in terms of packet recovery. Finally, we analyze different
spreading policies of the Tetrys redundancy traffic between available paths and
observe that the longer propagation delay path should be preferably used to
carry repair packets.Comment: Online multipath convolutional coding for real-time transmission
(2012
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