A Proposed Adaptive Bitrate Scheme Based on Bandwidth Prediction Algorithm for Smoothly Video Streaming

A robust video-bitrate adaptive scheme at client-aspect plays a significant role in keeping a good quality of video streaming technology experience. Video quality affects the amount of time the video has turned off playing due to the unfilled buffer state. Therefore to maintain a video streaming continuously with smooth bandwidth fluctuation, a video buffer structure based on adapting the video bitrate is considered in this work. Initially, the video buffer structure is formulated as an optimal control-theoretic problem that combines both video bitrate and video buffer feedback signals. While protecting the video buffer occupancy from exceeding the limited operating level can provide continuous video streaming, it may also cause a video bitrate oscillation. So the video buffer structure is adjusted by adding two thresholds as operating points for overflow and underflow states to filter the impact of throughput fluctuation on video buffer occupancy level. Then a bandwidth prediction algorithm is proposed for enhancing the performance of video bitrate adaptation. This algorithm's work depends on the current video buffer level, video bitrate of the previous segment, and iterative throughput measurements to predict the best video bitrate for the next segment. Simulation results show that reserving a bandwidth margin is better in adapting the video bitrate under bandwidth variation and then reducing the risk of video playback freezing. Simulation results proved that the playback freezing happens two times: firstly, when there is no bandwidth margin used and secondly, when the bandwidth margin is high while smooth video bitrate is obtained with moderate value. The proposed scheme is compared with other two schemes such as smoothed throughput rate (STR) and Buffer Based Rate (BBR) in terms of prediction error, QoE preferences, buffer size, and startup delay time, then the proposed scheme outperforms these schemes in attaining smooth video bitrates and continuous video playback.

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A quality of experience-aware cross-layer architecture for optimizing video streaming services

10.36227/techrxiv.12830543.v1 ◽

2020 ◽

Author(s):

qahhar muhammad qadir ◽

Alexander A. Kist ◽

ZHONGWEI ZHANG

Keyword(s):

Video Streaming ◽

Quality Of Experience ◽

Video Quality ◽

The Internet ◽

Cross Layer ◽

Video Traffic ◽

Adaptive Architecture ◽

Streaming Services ◽

Simulation Results

The popularity of the video services on the Internet has evolved various mechanisms that target the Quality of Experience (QoE) optimization of video traffic. The video quality has been enhanced through adapting the sending bitrates. However, rate adaptation alone is not sufficient for maintaining a good video QoE when congestion occurs. This paper presents a cross-layer architecture for video streaming that is QoE-aware. It combines adaptation capabilities of video applications and QoE-aware admission control to optimize the trade-off relationship between QoE and the number of admitted sessions. Simulation results showed the efficiency of the proposed architecture in terms of QoE and number of sessions compared to two other architectures (adaptive architecture and non-adaptive architecture ).

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Fuzzy Logic Control of Adaptive ARQ for Video Distribution over a Bluetooth Wireless Link

Advances in Multimedia ◽

10.1155/2007/45798 ◽

2007 ◽

Vol 2007 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

R. Razavi ◽

M. Fleury ◽

M. Ghanbari

Keyword(s):

Fuzzy Logic ◽

Fuzzy Logic Control ◽

Video Quality ◽

Video Stream ◽

Buffer Size ◽

Logic Control ◽

Video Distribution ◽

Channel Conditions ◽

The Impact ◽

Picture Type

Bluetooth's default automatic repeat request (ARQ) scheme is not suited to video distribution resulting in missed display and decoded deadlines. Adaptive ARQ with active discard of expired packets from the send buffer is an alternative approach. However, even with the addition of cross-layer adaptation to picture-type packet importance, ARQ is not ideal in conditions of a deteriorating RF channel. The paper presents fuzzy logic control of ARQ, based on send buffer fullness and the head-of-line packet's deadline. The advantage of the fuzzy logic approach, which also scales its output according to picture type importance, is that the impact of delay can be directly introduced to the model, causing retransmissions to be reduced compared to all other schemes. The scheme considers both the delay constraints of the video stream and at the same time avoids send buffer overflow. Tests explore a variety of Bluetooth send buffer sizes and channel conditions. For adverse channel conditions and buffer size, the tests show an improvement of at least 4 dB in video quality compared to nonfuzzy schemes. The scheme can be applied to any codec with I-, P-, and (possibly) B-slices by inspection of packet headers without the need for encoder intervention.

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Influence of Resolution and Frame Rate on the Linear In-Stream Video Ad QoE

JITA - Journal of Information Technology and Applications (Banja Luka) - APEIRON ◽

10.7251/jit1401015lj ◽

2014 ◽

Vol 7 (1) ◽

Author(s):

Miloš Ljubojević ◽

Vojkan Vasković ◽

Zdenka Babić ◽

Dušan Starčević

Keyword(s):

Video Streaming ◽

Quality Of Experience ◽

Objective Assessment ◽

Video Quality ◽

Rate Change ◽

Frame Rate ◽

Strong Impact ◽

Video Advertising ◽

The Impact

Abstract: An increasing number of services and facilities that are of interest to users is based on video streaming. Technical characteristics of video have a strong impact on the quality of a video streaming service and its perception by users. The most important measure of quality, which focuses on the user, is the Quality of Experience (QoE). Given that video advertising is a typical video streaming application, it is necessary to analyze the effect of the change of video characteristics on the QoE. This paper examines the impact of resolution and frame rate change on the QoE level by using objective and subjective QoE metrics. It also looks at the possibility of mapping the objective QoE metrics into subjective ones, if the QoE in Internet video advertising is analyzed. It was demonstrated that the values obtained by the objective assessment of quality can be mapped to the results obtained by subjective assessment of quality when the quality of experience of linear in- stream video ads is analyzed. The results indicate that temporal aspects of video quality assessment, e.g. influence of resolution and frame rate change to the level of the QoE, can be achieved by implementation of objective methods. Therefore, quality of experience can be improved by the proper selection of video characteristics values.

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QoS-based active dropping mechanism for NGN video streaming optimization

The Knowledge Engineering Review ◽

10.1017/s0269888914000186 ◽

2014 ◽

Vol 29 (4) ◽

pp. 484-495 ◽

Cited By ~ 2

Author(s):

Chi-Yuan Chen ◽

Tin-Yu Wu ◽

Wei-Tsong Lee ◽

Han-Chieh Chao ◽

Jen-Chun Chiang

Keyword(s):

Wireless Networks ◽

Video Streaming ◽

Scalable Video Coding ◽

Video Quality ◽

Buffer Management ◽

Base Station ◽

Effective Bandwidth ◽

Bandwidth Utilization ◽

Network Loading ◽

The Impact

AbstractVideo streaming over mobile wireless networks is getting popular in recent years. High video quality relies on large bandwidth provisioning, however, it decreases the number of supported users in wireless networks. Thus, effective bandwidth utilization becomes a crucial issue in wireless network as the bandwidth resource in wireless environment is precious and limited. The NGN quality of service mechanisms should be designed to reduce the impact of traffic burstiness on buffer management. For this reason, we propose an active dropping mechanism to deal with the effective bandwidth utilization in this paper. We use scalable video coding extension of H.264/AVC standard to provide different video quality for users of different levels. In the proposed dropping mechanism, when the network loading exceeds the threshold, the dropping mechanism starts to drop data of the enhancement layers for users of low service level. The dropping probability alters according to the change in network loading. With the dropping mechanism, the base station increases the system capability and users are able to obtain better service quality when the system is under heavy loading. We also design several methods to adjust the threshold value dynamically. By using the proposed mechanism, better quality can be provided when the network is in congestion.

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A quality of experience-aware cross-layer architecture for optimizing video streaming services

10.36227/techrxiv.12830543 ◽

2020 ◽

Author(s):

qahhar muhammad qadir ◽

Alexander A. Kist ◽

ZHONGWEI ZHANG

Keyword(s):

Video Streaming ◽

Quality Of Experience ◽

Video Quality ◽

The Internet ◽

Cross Layer ◽

Video Traffic ◽

Adaptive Architecture ◽

Streaming Services ◽

Simulation Results

The popularity of the video services on the Internet has evolved various mechanisms that target the Quality of Experience (QoE) optimization of video traffic. The video quality has been enhanced through adapting the sending bitrates. However, rate adaptation alone is not sufficient for maintaining a good video QoE when congestion occurs. This paper presents a cross-layer architecture for video streaming that is QoE-aware. It combines adaptation capabilities of video applications and QoE-aware admission control to optimize the trade-off relationship between QoE and the number of admitted sessions. Simulation results showed the efficiency of the proposed architecture in terms of QoE and number of sessions compared to two other architectures (adaptive architecture and non-adaptive architecture ).

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Measuring Hydrometeors Using a Precipitation Microphysical Characteristics Sensor: Sampling Effect of Different Bin Sizes on Drop Size Distribution Parameters

Advances in Meteorology ◽

10.1155/2018/9727345 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

Xichuan Liu ◽

Taichang Gao ◽

Yuntao Hu ◽

Xiaojian Shu

Keyword(s):

Drop Size ◽

Rain Rate ◽

Monte Carlo Model ◽

Rain Gauge ◽

Sampling Schemes ◽

Distribution Parameters ◽

Optimum Sampling ◽

Simulation Results ◽

The Impact ◽

Good Agreement

In order to improve the measurement of precipitation microphysical characteristics sensor (PMCS), the sampling process of raindrops by PMCS based on a particle-by-particle Monte-Carlo model was simulated to discuss the effect of different bin sizes on DSD measurement, and the optimum sampling bin sizes for PMCS were proposed based on the simulation results. The simulation results of five sampling schemes of bin sizes in four rain-rate categories show that the raw capture DSD has a significant fluctuation variation influenced by the capture probability, whereas the appropriate sampling bin size and width can reduce the impact of variation of raindrop number on DSD shape. A field measurement of a PMCS, an OTT PARSIVEL disdrometer, and a tipping bucket rain Gauge shows that the rain-rate and rainfall accumulations have good consistencies between PMCS, OTT, and Gauge; the DSD obtained by PMCS and OTT has a good agreement; the probability of N0, μ, and Λ shows that there is a good agreement between the Gamma parameters of PMCS and OTT; the fitted μ-Λ and Z-R relationship measured by PMCS is close to that measured by OTT, which validates the performance of PMCS on rain-rate, rainfall accumulation, and DSD related parameters.

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Fuzzy-Based Quality Adaptation Algorithm for Improving QoE from MPEG-DASH Video

Applied Sciences ◽

10.3390/app11115270 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5270

Author(s):

Waqas ur Rahman ◽

Md Delowar Hossain ◽

Eui-Nam Huh

Keyword(s):

State Of The Art ◽

Video Quality ◽

Buffer Size ◽

Bandwidth Utilization ◽

Adaptation Algorithm ◽

Control Laws ◽

Quality Video ◽

Video Player ◽

High Quality Video ◽

Abr Algorithm

Video clients employ HTTP-based adaptive bitrate (ABR) algorithms to optimize users’ quality of experience (QoE). ABR algorithms adopt video quality based on the network conditions during playback. The existing state-of-the-art ABR algorithms ignore the fact that video streaming services deploy segment durations differently in different services, and HTTP clients offer distinct buffer sizes. The existing ABR algorithms use fixed control laws and are designed with predefined client/server settings. As a result, adaptation algorithms fail to achieve optimal performance across a variety of video client settings and QoE objectives. We propose a buffer- and segment-aware fuzzy-based ABR algorithm that selects video rates for future video segments based on segment duration and the client’s buffer size in addition to throughput and playback buffer level. We demonstrate that the proposed algorithm guarantees high QoE across various video player settings and video content characteristics. The proposed algorithm efficiently utilizes bandwidth in order to download high-quality video segments and to guarantee high QoE. The results from our experiments reveal that the proposed adaptation algorithm outperforms state-of-the-art algorithms, providing improvements in average video rate, QoE, and bandwidth utilization, respectively, of 5% to 18%, about 13% to 30%, and up to 45%.

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A New Method to Determine the Impact of Individual Field Quantities on Cycle-to-Cycle Variations in a Spark-Ignited Gas Engine

Energies ◽

10.3390/en14144136 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4136

Author(s):

Clemens Gößnitzer ◽

Shawn Givler

Keyword(s):

Kinetic Energy ◽

Flow Field ◽

Turbulent Kinetic Energy ◽

Negative Impact ◽

Operating Conditions ◽

Engine Operation ◽

Gas Engine ◽

Cycle Simulation ◽

Simulation Results ◽

The Impact

Cycle-to-cycle variations (CCV) in spark-ignited (SI) engines impose performance limitations and in the extreme limit can lead to very strong, potentially damaging cycles. Thus, CCV force sub-optimal engine operating conditions. A deeper understanding of CCV is key to enabling control strategies, improving engine design and reducing the negative impact of CCV on engine operation. This paper presents a new simulation strategy which allows investigation of the impact of individual physical quantities (e.g., flow field or turbulence quantities) on CCV separately. As a first step, multi-cycle unsteady Reynolds-averaged Navier–Stokes (uRANS) computational fluid dynamics (CFD) simulations of a spark-ignited natural gas engine are performed. For each cycle, simulation results just prior to each spark timing are taken. Next, simulation results from different cycles are combined: one quantity, e.g., the flow field, is extracted from a snapshot of one given cycle, and all other quantities are taken from a snapshot from a different cycle. Such a combination yields a new snapshot. With the combined snapshot, the simulation is continued until the end of combustion. The results obtained with combined snapshots show that the velocity field seems to have the highest impact on CCV. Turbulence intensity, quantified by the turbulent kinetic energy and turbulent kinetic energy dissipation rate, has a similar value for all snapshots. Thus, their impact on CCV is small compared to the flow field. This novel methodology is very flexible and allows investigation of the sources of CCV which have been difficult to investigate in the past.

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Impact of Scene Content on High Resolution Video Quality

Sensors ◽

10.3390/s21082872 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2872

Author(s):

Miroslav Uhrina ◽

Anna Holesova ◽

Juraj Bienik ◽

Lukas Sevcik

Keyword(s):

Video Compression ◽

Spatial Information ◽

Video Quality ◽

Video Sequences ◽

Compression Efficiency ◽

Opinion Score ◽

Scene Description ◽

Two Parameters ◽

The University ◽

The Impact

This paper deals with the impact of content on the perceived video quality evaluated using the subjective Absolute Category Rating (ACR) method. The assessment was conducted on eight types of video sequences with diverse content obtained from the SJTU dataset. The sequences were encoded at 5 different constant bitrates in two widely video compression standards H.264/AVC and H.265/HEVC at Full HD and Ultra HD resolutions, which means 160 annotated video sequences were created. The length of Group of Pictures (GOP) was set to half the framerate value, as is typical for video intended for transmission over a noisy communication channel. The evaluation was performed in two laboratories: one situated at the University of Zilina, and the second at the VSB—Technical University in Ostrava. The results acquired in both laboratories reached/showed a high correlation. Notwithstanding the fact that the sequences with low Spatial Information (SI) and Temporal Information (TI) values reached better Mean Opinion Score (MOS) score than the sequences with higher SI and TI values, these two parameters are not sufficient for scene description, and this domain should be the subject of further research. The evaluation results led us to the conclusion that it is unnecessary to use the H.265/HEVC codec for compression of Full HD sequences and the compression efficiency of the H.265 codec by the Ultra HD resolution reaches the compression efficiency of both codecs by the Full HD resolution. This paper also includes the recommendations for minimum bitrate thresholds at which the video sequences at both resolutions retain good and fair subjectively perceived quality.

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