6 research outputs found

    A Cross Layer Model to Support QoS for Multimedia Applications on Wireless Networks

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    Supporting multimedia application over wireless networks poses multiple challenges. Currently the use of cross layer architectures and Scalable Video Coding ( ) techniques are considered to support multimedia applications. The current architectures fail to address the tradeoff that exists between the end to end delay and the Quality of Service ( ) provisioning of the video data to be delivered. To address this issue this paper introduces the improvement scheme in video transmission model based on a cross layer architecture. A novel encoding of the SVC video is considered in the proposed model. Based on the physical layer conditions and the achievable the model adapts to meet the stringent delay requirements of video delivery. Routing layer optimization is achieved by accounting for the pending packets queues in every neighboring node. The experimental study conducted prove the robustness of the proposed model by comparing with the existing schemes. Comparisons in terms of the transmission error rates, system utility and quality of reconstruction are presented

    Evaluation of Wirelessly Transmitted Video Quality Using a Modular Fuzzy Logic System

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    Video transmission over wireless computer networks is increasingly popular as new applications emerge and wireless networks become more widespread and reliable. An ability to quantify the quality of a video transmitted using a wireless computer network is important for determining network performance and its improvement. The process requires analysing the images making up the video from the point of view of noise and associated distortion as well as traffic parameters represented by packet delay, jitter and loss. In this study a modular fuzzy logic based system was developed to quantify the quality of video transmission over a wireless computer network. Peak signal to noise ratio, structural similarity index and image difference were used to represent the user's quality of experience (QoE) while packet delay, jitter and percentage packet loss ratio were used to represent traffic related quality of service (QoS). An overall measure of the video quality was obtained by combining QoE and QoS values. Systematic sampling was used to reduce the number of images processed and a novel scheme was devised whereby the images were partitioned to more sensitively localize distortions. To further validate the developed system, a subjective test involving 25 participants graded the quality of the received video. The image partitioning significantly improved the video quality evaluation. The subjective test results correlated with the developed fuzzy logic approach. The video quality assessment developed in this study was compared against a method that uses spatial efficient entropic differencing and consistent results were observed. The study indicated that the developed fuzzy logic approaches could accurately determine the quality of a wirelessly transmitted video

    Mechanisms for QoE optimisation of video traffic: a review paper

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    Transmission of video traffic over the Internet has grown exponentially in the past few years with no sign of waning. This increasing demand for video services has changed user expectation of quality. Various mechanisms have been proposed to optimise the Quality of Experience (QoE) of end users’ video. Studying these approaches are necessary for new methods to be proposed or combination of existing ones to be tailored. We discuss challenges facing the optimisation of QoE for video traffic in this paper. It surveys and classifies these mechanisms based on their functions. The limitation of each of them is identified and future directions are highlighted

    MIMO無線伝送に適したスケーラブルビデオコーディングに関する研究

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    Because of the COVID-19 pandemic, a new normal has taken over. It affects the higher demand for using video traffic. H.264/SVC is the video compression standard with several advantages compared with the previous standard, such as a smaller storage space and scalability of video quality depending on network quality. The H.264/SVC bitstream includes one base layer (BL), the most important layer, and one or more enhancement layers (EL) which can be leveraged to optimize the video scalability depending on the network condition and user preferences. The method of transmission is powerful as the video coding method. The transmission of the good video quality will not be effective without a suitable transmission method. In this thesis, we study and research the H.264 scalable video coding transmission with IEEE 802.11ac standard MIMO wireless transmission. We focus on the suitable transmission method for H.264/SVC in a different environment. We divide the research focusing on two issues: 1. With the difference channel environment: The suitable H.264/SVC transmission technique in IEEE 802.11ac with the specific quantization parameter of video encoding was proposed. This aim is to compare three techniques in IEEE 802.11ac: STBC, SISO, and MIMO. In this focus, only the accuracy of the video was considered to measure the efficiency of the transmission technique. This part proposed to utilize STBC to improve the quality of H.264/SVC video transmission. We have shown the performance of H.264/SVC video transmission with three multiple antenna techniques. The results show that STBC is the best technique for H.264/SVC transmission under a low-quality channel environment. The best result shows that STBC in channel model D can improve the PSNR by 67 percent and 76 percent compared with SISO and MIMO, respectively, at low SNR of 20 dB. Due to STBC transmitting multiple copies of data, it can increase data reliability. We proved that STBC is the most suitable multiple antenna technique to improve the quality and realizability of video transmission in both PSNR and bit error rate (BER). 2. With the different transmission distance: H.264/SVC video transmission on MIMO with RSSI feedback was proposed. This aim to proposes the allocation of packetization in the transmission packet and the compromising of quantization parameter encoding both vary on the channel efficiency. This part proposed a MIMO transmission system for H.264 scalable video coding that does not require full CSI feedback. Instead of the CSI feedback, we have used the RSSI and table of encoding rules obtained via link simulation in MATLAB. The encoding rule takes the form of the encoding ratio between the base and enhancement layer, which was done by adjusting the quantization parameter. This proposed system has been shown to improve the PSNR by at least 16 dB and increase the effective distance of 6 meters above compared with the conventional method.九州工業大学博士学位論文 学位記番号:情工博甲第372号 学位授与年月日:令和4年12月27日1 Introduction|2 Video Transmission System Overview|3 H.264/SVC Video Transmission by IEEE 802.11ac Techniques|4 H.264/SVC Video Transmission on MIMO with RSSI Feedback|5 Conclusion and Future Work九州工業大学令和4年
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