130 research outputs found
Video Compression and Optimization Technologies - Review
The use of video streaming is constantly increasing. High-resolution video requires resources on both the sender and the receiver side. There are many compression techniques that can be utilized to compress the video and simultaneously maintain quality. The main goal of this paper is to provide an overview of video streaming and QoE. This paper describes the basic concepts and discusses existing methodologies to measure QoE. Subjective, objective, and video compression technologies are discussed. This review paper gathers the codec implementation developed by MPEG, Google, and Apple. This paper outlines the challenges and future research directions that should be considered in the measurement and assessment of quality of experience for video services
Implementation of 4kUHD HEVC-content transmission
The Internet of things (IoT) has received a great deal of attention in recent years, and is still being approached with a wide range of views. At the same time, video data now accounts for over half of the internet traffic. With the current availability of beyond high definition, it is worth understanding the performance effects, especially for real-time applications. High Efficiency Video Coding (HEVC) aims to provide reduction in bandwidth utilisation while maintaining perceived video quality in comparison with its predecessor codecs. Its adoption aims to provide for areas such as television broadcast, multimedia streaming/storage, and mobile communications with significant improvements. Although there have been attempts at HEVC streaming, the literature/implementations offered do not take into consideration changes in the HEVC specifications. Beyond this point, it seems little research exists on real-time HEVC coded content live streaming. Our contribution fills this current gap in enabling compliant and real-time networked HEVC visual applications. This is done implementing a technique for real-time HEVC encapsulation in MPEG-2 Transmission Stream (MPEG-2 TS) and HTTP Live Streaming (HLS), thereby removing the need for multi-platform clients to receive and decode HEVC streams. It is taken further by evaluating the transmission of 4k UHDTV HEVC-coded content in a typical wireless environment using both computers and mobile devices, while considering well-known factors such as obstruction, interference and other unseen factors that affect the network performance and video quality. Our results suggest that 4kUHD can be streamed at 13.5 Mb/s, and can be delivered to multiple devices without loss in perceived quality
Evaluation of H.265 Video Delivery Based on Dynamic Adaptive Streaming over HTTP (DASH) Using Mobile Devices
MPEG Dynamic Adaptive Streaming over HTTP (MPEG-DASH) is a standard for HTTP streaming that allows interoperability between servers and clients from different vendors which is able to adjust the speed of video delivery to changing bandwidth. Today there is the latest H.265 video coding known as the High Efficiency Video Coding (HEVC). This research implemented the delivery of the H.265 video through the method of Dynamic Adaptive Streaming over HTTP (DASH) using mobile devices. The test was conducted by sending videos over 3G networks with GSM length video segment consists of 2 seconds, 5 seconds, 10 seconds and 20 seconds. The video quality provided in this study consisted of 5 video levels with different bit rates. From the test results, the submitted videos using a smaller video segment generated greater throughput and acquired more video quality with a higher bit rate than the video to a larger segment. Video delivery with segment of 2 seconds acquired video quality with the highest level of 83%, meanwhile the video delivery segment of 20 seconds obtained video quality with the highest level of 33%
Video Quality Evaluation for Tile-Based Spatial Adaptation
The demand for very high-resolution video
content in entertainment services (4K, 8K, panoramic,
360 VR) puts an increasing load on the distribution
network. In order to reduce the network usage in
existing delivery infrastructure for such services while
keeping a good quality of experience, dynamic spatial
video adaptation at the client side is seen as a key
feature, and is actively investigated by academics and
industrials. However, the impact of spatial adaptation
on quality perception is not clear. In this paper, we propose
a methodology for the evaluation of such adapted
content, conduct a series of perceived quality measurements
and discuss results showing potential benefits
and drawbacks of the technique. Based on our results,
we also propose a signaling mechanism in MPEGDASH
to assist the client in its spatial adaptation log
Streaming and User Behaviour in Omnidirectional Videos
Omnidirectional videos (ODVs) have gone beyond the passive paradigm of traditional video,
offering higher degrees of immersion and interaction. The revolutionary novelty of this technology is the possibility for users to interact with the surrounding environment, and to feel a
sense of engagement and presence in a virtual space. Users are clearly the main driving force of
immersive applications and consequentially the services need to be properly tailored to them.
In this context, this chapter highlights the importance of the new role of users in ODV streaming applications, and thus the need for understanding their behaviour while navigating within
ODVs. A comprehensive overview of the research efforts aimed at advancing ODV streaming
systems is also presented. In particular, the state-of-the-art solutions under examination in this
chapter are distinguished in terms of system-centric and user-centric streaming approaches: the
former approach comes from a quite straightforward extension of well-established solutions for
the 2D video pipeline while the latter one takes the benefit of understanding users’ behaviour
and enable more personalised ODV streaming
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