Panos K Papadopoulos

University of Thessaly | UTH · Computer Science and Biomedical Informatics

High Efficiency Video Coding (HEVC) was developed to tackle the 4K resolution era, achieving up to 50% more compression efficiency (for the same video quality) compared to its predecessor H.264/AVC. However, this performance improvement comes at the expense of increased coding time. In order to ameliorate the situation, HEVC provides three coarse g...

Technological advances in Cloud computing and networking are offering unique opportunities for assisting everyday activities of visually impaired persons. Of particular interest is the capitalization of these technologies in the domain of aiding mobility and environment perception. In this chapter, we describe a generic system architecture design a...

Video is by far the “biggest” Big Data, stretching network and storage capacity to their limits. To handle the situation, video compression has been an active field of study for many years, producing output of huge commercial interest, e.g., MPEG-2 and DVD. However, video coding is a computationally expensive process and for this reason, paralleliz...

Video coding incurs high computational complexity particularly at the encoder side. For this reason, parallelism is used at the various encoding steps. One of the popular coarse grained parallelization tools offered by many standards is wavefront parallelism. Under the scheme, each row of blocks is assigned to a separate thread for processing. A th...

The advent of 4K and 8K resolutions in cameras and TV sets, posed a challenge to Video on Demand (VoD) and live streaming industry since the network overhead compared to FullHD was multiplied. For this reason, new video coding standards were launched as successors to the ageing H.264/AVC that dominated the DVD era. Arguably, the most prominent exam...

Video transcoding is the process of encoding an initial video sequence into multiple sequences of different bitrates, resolutions, and video standards, so that it can be viewed on devices of various capabilities and with various network access characteristics. Because video coding is a computationally expensive process and the amount of video in so...

The collaborative learning paradigm offers one of the most solid approaches to increase the participation, interest and knowledge level of pupils (typical achieving and/or learning disabled students) during the educational process. Recent advances in the field have offered a plethora of tools to facilitate collaboration during school time. Neverthe...

HEVC has emerged as the new video coding standard promising improved compression ratios (for the same quality) by up to 50% compared to H.264/AVC. To achieve this performance HEVC requires increased computational overhead compared to its predecessor. For this reason parallelism is used, usually at a coarse grained level, e.g., per slice or tile. In...

In recent years, we have witnessed an explosion in the growth of social media networks, powered by the proliferation of handheld smart devices with high processing capabilities and a plethora of sensors including high-resolution cameras. A key component of information exchange in such networks, accounting for the majority of network traffic, is vid...

HEVC has emerged as the new video standard to replace H.264/AVC. Although the new standard is able to achieve significantly higher compression ratios compared to the older one, it entails high computational demands. To alleviate the problem, parallelism opportunities are offered by the standard at different levels namely, slice, tile and wave front...

The ever increasing number of video uploads in social media platforms, together with the incorporation of live video broadcasts and a growing demand for higher video resolution, will likely pose the most significant performance challenge for social media providers in the years to come. The current state of the art in most social media platforms, in...

Mobile applications (apps) have become part of our everyday life with a constantly increasing market. Of particular interest are apps aiding planning and collaboration among family members, or between co-workers. The architecture of such apps usually involves some Cloud storage medium, through which group members post and retrieve data. Naturally,...