I joined Film and Video Production Technology as a Lecturer in 2017. Prior to this, I work at Kingston University on a Knowledge Transfer Partnership (KTP) project which developed a prototype Analogue-Hybrid Multi-Occupant Visitor communication interface for door intercom systems, in collaboration. I was awarded a PhD from the University of Essex in 2015 with my thesis, entitled: “Ultra-High Definition Wireless Video Streaming”, which was concerned with enhanced compression techniques for 4k and 8k UHDTV with particular emphasis on wireless and IP network applications, with part of my research leading to the trials of Internet broadcast of 4k UHDTV in 2014.
Areas of specialism
University roles and responsibilities
- Senior Placement Tutor, Film and Video Production Technology
- Deputy Chair, Early Career Researchers Forum
- Programme leader, PhD Innovative Media Technology
Affiliations and memberships
My research interests both video compression and transmission which includes video processing, audiovisual transmission and display. I have been involved in proposing solutions for the beyond high definition transport. This has led me to explore computationally efficient ways of video compression including the use of graphic processing units(GPU). In 2014, I contributed significantly to the implementation of the first 4kUHD broadcast over the Internet and this was presented at the prestigious International Broadcast Convention (IBC) in Amsterdam.
Another impact of his research, was the real-time implementation of carriage of high efficiency video coding (HEVC) content over MPEG2-TS and subsequently http live streaming, which was as a result of research into the transmission of 8K UHD video content over wireless. A part of the software code development for this solution is available online as part of the open source FFMPEG software repository.
My other interests relating to video compression and transmission are:
Quality of experience provision in wireless multimedia networks, error resilient video transmission, image/video quality assessment, frame synchronization and the application of knowledge from video transmission to everyday lives (video door entry systems and Smart homes).
Right-Time performance is key to railway customers having a good journey on the railways and fatalities are a major source of disruption. These incidents cause lines to be closed whilst British Transport Police (BTP) investigate and the railway is readied to reopen. TRUST data extracted by the National Disruption Fusion Unit of Network Rail (NR) show that, on average, there have been approximately 350 fatalities pa on GB railways causing 790,000 Delay Minutes pa, equating to 2,300 Delay Minutes per incident.
In response, this project will use emergent 8K video technology, Cloud technology and advanced Artificial Intelligence image recognition to provide BTP with high-quality video they can forensically analyse quickly. With better recordings, more incidents that would be judged as Unexplained due to current technology limitations will correctly be deemed as suicides, reducing hand-back time and alleviating wider customer disruption.
Co-Investigator: 9-month project and is one of the winners of the latest round of the 2021 First of a Kind (FOAK) competition funded by SBRI: the Small Business Research Initiative (Total funding:£396,349). It is led by Rail Innovations and also includes One Big Circle Ltd, Avanti West Coast and Angel Trains Ltd as project partners.
Subjective test methodologies for 360º video on head-mounted display
An international collaboration involving 10 labs and more than 300 participants. This collaboration involved members of the Immersive Media Group (IMG) of the Video Quality Experts Group (VQEG).
The results from this collaboration led to the development of ITU-T Recommendation P.919
Indicators of esteem
Postgraduate research supervision
Research at the Innovative Media Lab (IML) is based on understanding perceptual video quality and developing perceptually-optimised signal processing approaches to improve them.
Please contact me if you are interested in pursuing a PhD at IML
Student consultationIf you would like to book an appointment to discuss any of the modules below, please click here.
- FVP2006 Computer Imaging and Systems B
- FVP1013 Computer Systems
- FVP3014 Reseach methods
- FVP3012 Technical Project
Modules I teach on:
- FVP2006 Computer Imaging and Systems B
- FVP1013 Computer Systems
- TON1024 Computer Systems
- FVP3012 Technical Project
Courses I teach on
This paper proposes a prediction model for the perceptual quality of wireless 4kUHD H.265 video streaming. Based on Interval Type-2 Fuzzy Logic System (IT2FLS), the model exploits application and physical layer parameters. The results show that good prediction accuracy was obtained from the proposed prediction model. This study should help in the development of a reference-free video quality prediction model and QoS control methods for 4kUHD video streaming.
Networked visual applications such video streaming have grown exponentially in recent years, yet are known to be sensitive to network impairments. However, available measurement techniques that adopt a full reference model are impractical in real-time streaming because they require the original video sequence available at the receivers side. The primary aim of this study is to present a hybrid no-reference prediction model for the perceptual quality of 4kUHD H.265-coded video in the wireless domain. The contributions of this paper are two-fold: first, an investigation of the impact of quality of service (QoS) parameters on 4kUHD H.265-coded video transmission in an experimental environment; second, objective model based on fuzzy logic inference system is developed to predict the visual quality by mapping QoS parameters to the measured quality of experience. The model is evaluated in contrast to random neural networks. The results show that good prediction accuracy was obtained from the proposed hybrid prediction model. This study will help in the development of a reference-free video quality prediction model and QoS control methods for 4kUHD video streaming.
Door phone systems, allowing occupants of a building to communicate with visitors at the door, have evolved over the years, with the current advancements being a fully internet protocol (IP) based solution. In order to adopt newer IP based solutions, current analogue systems can be replaced, yet this may be costly and cumbersome, especially in a conventional multioccupant building. We therefore propose an architecture which supports current analogue door phone systems, and also provides IP based functionality. We have implemented the proposed architecture based on SIP, WebRTC and an IoT gateway system connected to the multi-occupant conventional video door phone system.
This paper examines the 4kUHD video quality from streaming over an IEEE 802.11ac wireless channel, given measured levels of packet loss. Findings suggest that there is a strong content dependency to loss impact upon video quality but that, for short-range transmission, the quality is acceptable, making 4kUHD feasible on head-mounted displays.
After adjusting for coding gain between the H.264 and HEVC codecs, a comparison is made between the two codecs’ robustness to packet loss. A counter-intuitive finding arises that the less efficient codec is less affected by packet loss than the more efficient codec, even at very low levels of packet loss. The findings will be of interest to those designing portable devices that can display up to 4kUHD video.
The trend towards video streaming with increased spatial resolutions and dimensions, SD, HD, 3D, and 4kUHD, even for portable devices has important implications for displayed video quality. There is an interplay between packetization, packet loss visibility, choice of codec, and viewing conditions, which implies that prior studies at lower resolutions may not be as relevant. This paper presents two sets of experiments, the one at a Variable BitRate (VBR) and the other at a Constant BitRate(CBR), which highlight different aspects of the interpretation. The latter experiments also compare and contrast encoding with either an H.264 or an High Efficiency Video Coding (HEVC) codec, with all results recorded as objective Mean Opinion Score (MOS). The video quality assessments will be of interest to those considering: the bitrates and expected quality in error-prone environments; or, in fact, whether to use a reliable transport protocol to prevent all errors, at a cost in jitter and latency, rather than tolerate low levels of packet errors.
From a review of the literature and a range of experiments, this paper demonstrates that live video streaming to mobile devices with pixel resolutions from Standard Definition up to 4k Ultra High Definition (UHD) is now becoming feasible by means of high-throughput IEEE 802.11ad at 60 GHz or 802.11ac at 5 GHz, and 4kUHD streaming is even possible with 802.11n operating at 5 GHz. The paper, by a customized implementation, also shows that real-time compression, assisted by Graphical Processing Units (GPUs) at 4kUHD, is also becoming feasible. The paper further considers the impact of packet loss on H.264/AVC and HEVC codec compressed video streams in terms of Structural Similarity (SSIM) index video quality. It additionally gives an indication of wireless network latencies and currently feasible frame rates. Findings suggest that, for medium-range transmission, the video quality may be acceptable at low packet loss rates. For hardware-accelerated 4kUHD encoding, standard frame rates may be possible but appropriate higher frame rates are only just being reached in hardware implementations. The target bitrate was found to be important in determining the display quality, which depends on the coding complexity of the video content. Higher compressed bitrates are recommended, as video quality may improve disproportionately as a result.
—Recently an impressive development in immersive technologies, such as Augmented Reality (AR), Virtual Reality (VR) and 360° video, has been witnessed. However, methods for quality assessment have not been keeping up. This paper studies quality assessment of 360° video from the cross-lab tests (involving ten laboratories and more than 300 participants) carried out by the Immersive Media Group (IMG) of the Video Quality Experts Group (VQEG). These tests were addressed to assess and validate subjective evaluation methodologies for 360° video. Audiovisual quality, simulator sickness symptoms, and exploration behavior were evaluated with short (from 10 seconds to 30 seconds) 360° sequences. The following factors’ influences were also analyzed: assessment methodology, sequence.
Ultra High Definition (UHD) video streaming to portable devices has become topical. Two standardized codecs are current, H.264/Advanced Video Coding (AVC) and the more recent High Efficiency Video Coding (HEVC). This paper compares the two codecs’ robustness to packet loss, after making allowances for relative coding gain. A significant finding from the comparison is that the H.264/AVC codec is less impacted by packet loss than HEVC, despite their differing coding efficiencies and including at low levels of packet loss. The results will be especially relevant to those designing portable devices with 4K UHD video display capability, allowing them to estimate the level of error concealment necessary. The paper also includes the results of HEVC compressed UHD video streaming over an IEEE 802.11ad wireless link operating at 60 GHz as a pointer to future performance in an error-prone channel.
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.