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1

Proposal of a tool for the automatic estimation of quality of experience in MPEG-DASH scenarios

Atehortua Johnny, Muñoz Wilmar Yesid Campo, Golondrino Gabriel Elías Chanchí

Przegląd Elektrotechniczny

|

2022

|

R. 98, nr 8

139--145

EN

Service providers must be able to identify the quality perceived by users through data networks, which is the quality of experience (QoE) required to take the necessary actions to provide a service that meets the user’s expectations. Therefore, this article proposes a tool for estimating the subjective QoE from objective parameters of the quality of service (QoS) for the video streaming supported by MPEG-DASH (Moving Picture Experts Group- Dynamic Adaptive Strea.

PL

Dostawcy usług muszą być w stanie określić jakość postrzeganą przez użytkowników za pośrednictwem sieci danych, czyli jakość doświadczenia (QoE) wymaganą do podjęcia niezbędnych działań w celu świadczenia usługi spełniającej oczekiwania użytkownika. Dlatego w niniejszym artykule zaproponowano narzędzie do szacowania subiektywnego QoE na podstawie obiektywnych parametrów jakości usług (QoS) dla strumieniowego przesyłania wideo obsługiwanego przez MPEG-DASH (Moving Picture Experts Group - Dynamic Adaptive Streaming over HTTP). W przyszłych pracach proponujemy ekstrapolację opracowanego narzędzia na usługi wideo na żądanie w różnych kontekstach aplikacji.

2

Telecom Operator’s Approach to QoE

Kowalik Karol, Andruloniw Paweł, Partyka Bartosz, Zwierzykowski Piotr

Journal of Telecommunications and Information Technology

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2022

|

nr 2

26--34

EN

Telecommunication networks are ever more frequently relying on artificial intelligence and machine learning techniques to detect specific use patterns or potential errors and to take automated decisions when these are encountered. This concept requires that methods be employed to measure the level of quality of a given telecommunication service, i.e. to verify quality of service (QoS) metrics. In a broader context, methods assessing the entire user experience (quality of experience – QoE) are required as well. In this article, various approaches to assessing QoS, QoE and the related metrics are presented, with a view to implement these at an FTTH network operator in Poland. Since this article presents the architecture of the system used to analyze QoE performance based on a number of QoS metrics collected by the operator, we also provide a comprehensive introduction to the QoS and QoE metrics used herein.

3

The quality of video communication in encrypted traffic

Łubkowski Piotr, Laskowski Dariusz

Journal of KONBiN

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2020

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Vol. 50, iss. 4

165--180

EN

The rapid development of network and computer technologies creates opportunities for offering advanced broadband multimedia services to a growing numer of end users. Instant messaging and group communication services based on real-time video transmission based on global Internet resources are the most popular. The basic challenge related to the implementation of video transmission services is to ensure an appropriate level of quality and security (Quality & Security). The article presents a multi-criteria assessment of the impact of encryption protocols for multimedia video transmissions on the perceived quality of QoE (Quality of Experience) service implementation. The presented measurement method together with the proposed research methodology create the possibility of determining the likelihood of video service availability with accepted QoE in heterogeneous networks.

PL

Gwałtowny rozwój technologii sieciowych i komputerowych stwarza możliwości oferowania zaawansowanych szerokopasmowych usług multimedialnych coraz szerszemu gronu użytkowników końcowych. Największą popularnością cieszą się usługi komunikacji natychmiastowej i grupowej bazujące na transmisji obrazu wideo w czasie rzeczywistym w oparciu o zasoby globalnego Internetu. Podstawowym wyzwaniem związanych z realizacją usług transmisji wideo jest zapewnienie odpowiedniego poziomu jakości i bezpieczeństwa (Quality&Security). W artykule zaprezentowano wielokryterialną ocenę wpływu protokołów szyfrowania multimedialnych transmisji wideo na postrzeganą jakość realizacji usługi QoE. Przedstawiona metoda pomiarowa wraz z zaproponowaną metodyką ba-dawczą stwarzają możliwość wyznaczenia prawdopodobieństwa dostępności usługi wideo o akceptowanej QoE w sieciach heterogenicznych.

4

Measurements and Statistical Analysis for Assessment of Availability of Mobile Network Services

Kadamus G., Langer M.

Journal of Telecommunications and Information Technology

|

2018

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nr 2

48--52

EN

Availability is an essential feature of telecommunication services. It inﬂuences the quality of experience (QoE) associated with individual networks and with the services offered. Therefore, it needs to be allowed for at each level of network design, and has to be controlled at the operation stage. This is achieved by means of various mathematical and numerical tools. In this project listening quality and speech level, which are quality-related features of mobile network services, are measured and analyzed with the Monte Carlo simulation method. Measurements are taken with assistance of the Diversity Benchmarker, a reliable device designed for mobile network testing. Finally, results obtained are compared to assess the applicability of the Monte Carlo method.

5

Dimensioning aspects of SMS systems in mobile networks

Klink J., Uhl T.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2017

|

nr 49 (121)

110--118

EN

This paper focuses on factors affecting the dimensioning of Short Message Service (SMS) systems in mobile communications networks. Problems associated with Quality of Service (QoS) in modern communications networks in general are described, along with the main parameters that define QoS in SMS systems. The functionality of the SMS in terms of European Telecommunications Standards Institute (ETSI) standards is then explained. The creation of a queuing model is described for an SMS system which is based on ETSI documentation and will be analysed in calculations. The parameter completion rate plays an important role in SMS. Practical aspects of the End-to-End (E2E) delivery time for SMS systems are also discussed. The approach suggested in this paper and the insights gained in the course of this work can be of valuable practical use in the planning and analysis of real SMS systems.

6

Quality Aspects in Digital Broadcasting and Webcasting Systems: Bitrate versus Loudness

Gilski P., Gajewski S., Stefański J.

Journal of Telecommunications and Information Technology

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2017

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nr 2

26--31

EN

In this paper the quality aspects of bitrate and loudness in digital broadcasting and webcasting systems are examined. The authors discuss a survey concerning user preferences related with processing and managing audio content. The coding efficiency of a popular audio format is analyzed in the context of storing media. An objective study on a representative group of signal samples, as well as a subjective study of the perceived quality of real-time broadcasted and webcasted radio programs are performed.

7

Subjective and Objective Comparative Study of DAB+ Broadcast System

Gilski P., Stefański J.

Archives of Acoustics

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2017

|

Vol. 42, No. 1

3--11

EN

Broadcasting services seek to optimize their use of bandwidth in order to maximize user’s quality of experience. They aim to transmit high-quality digital speech and music signals at the lowest bitrate. They intend to offer the best quality under available conditions. Due to bandwidth limitations, audio quality is in conflict with the number of transmitted radio programs. This paper analyzes whether the quality of real-time digital DAB+ broadcasted radio programs surpasses the quality offered by analog FM radio. We also perform a subjective and objective quality assessment comparative study of the HE-AAC v2 audio codec used in DAB+. The subjective studies were carried out using the MOS test methodology, whereas the objective tests were realized using the ViSQOLAudio metric. These studies were followed by a questionnaire concerning the migration from analog to digital radio domain.

8

DAB vs DAB+ Radio Broadcasting : a Subjective Comparative Study

Gilski P.

Archives of Acoustics

|

2017

|

Vol. 42, No. 4

715--723

EN

In the age of digital media, delivering high quality content to consumers is one of the most demanding tasks. There exist numerous broadcasting standards, with different pros and cons, and the DAB/DAB+ (Digital Audio Broadcasting) system is one of the most popular among them. From an engineer’s perspective, efficient resource management under limited bandwidth conditions has always been a challenge. In this paper a subjective quality assessment study of the DAB and DAB+ broadcasting system is performer on a representative group of signal samples. It describes the radio link, including a fully functional transmitter designed for the purpose of this test, as well as the receiver side representing a commercially available consumer device, for a truly real-time and end-to-end quality evaluation.

9

The method for quality of experience evaluation of IT services

Mokkas M., Księżopolski B.

Studia Informatica

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2016

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Vol. 37, nr 2

73--84

EN

Quality of Experience (QoE) is one of the major aspects that service providers focus on during development of their services. However QoE elements that are meant to increase user satisfaction are sometimes contradicting with Quality of Service (QoS) or Quality of Protection (QoP) factors. In order to balance the QoE to QoS or QoP values ratio we propose a method that takes into account various configurations of parameters and their relations and based on their state and values evaluates the QoE levels. The proposed method includes a model which describes the elements, their relations and the stages in which they are defined and used.

PL

Jakość doświadczeń (QoE) jest jednym z najistotniejszych aspektów, nad którym usługodawcy powinni się skupić podczas budowy swoich usług. Często elementy QoE, które mają za zadanie zwiększyć satysfakcję użytkowników, niestety są sprzeczne z czynnikami jakości usług (QoS) oraz jakości ochrony (QoP). W celu zrównoważenia proporcji wartości QoE z QoS lub QoP proponujemy metodę, która wykorzystuje różne konfiguracje parametrów oraz ich relacje i bazując na ich stanie i wartościach, określa poziomy QoE. Metoda ta zawiera model, który opisuje elementy, ich relacje oraz etapy ich definiowania i wykorzystania.

10

Badanie możliwości crowdsourcingowej oceny jakości zdjęć

Zajdel M., Leszczuk M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2016

|

nr 6

483--486, CD

PL

Zautomatyzowane (korzystające ze źródeł internetowych) generowanie czasopism cyfrowych może spowodować pobranie zdjęć o niskiej jakości. Dlatego w tym artykule prezentujemy praktyczne rozwiązanie problemu automatycznego wykrywania zdjęć o niskiej jakości, oparte na odpowiednio wytrenowanym, uprzednio stworzonym systemie oceny jakości zdjęć, oceniającym pikselizację, rozmycie, kontrast i szum, w trybie No-Reference.

EN

Automated (using the Internet sources) generation of digital magazines, may cause downloading images with low quality. Therefore, in this paper we present a practical solution to the problem of automatic detection of images with low quality, based on a sufficiently trained, previously created image quality evaluation system, assessing blockiness, blur, contrast and noise in a No-Reference approach.

11

Study of No-Reference Video Quality Metrics for HEVC Compression

Rouis K., Leszczuk M., Janowski M., Papir Z., Tahar J. B. H.

Journal of Telecommunications and Information Technology

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2016

|

nr 1

22--28

EN

The paper proposes a No-Reference (NR) quality assessment measurement originally developed for H.264, used for High Efficiency Video Coding (HEVC). In particular, authors present an investigation of NR metrics to objectively estimate the perceptual quality of a set of processed video sequences. The authors take into account typical distortions introduced by the block-based coding approaches like HEVC codec. The underlying processing used for the quality assessment considers the blockiness caused by the boundaries of each coded block and the blurring as a lack of spatial details. The correlation between the NR quality metrics and the well-known and most widely used objective metric, the Video Quality Model (VQM), is performed to validate the quality prediction accuracy based on the provided scores. The Pearson correlation coefficients obtained stand for promising results for different types of videos.

12

Digital Audio Broadcasting or Webcasting: A Network Quality Perspective

Gilski P., Stefański J.

Journal of Telecommunications and Information Technology

|

2016

|

nr 1

9--15

EN

In recent years, many alternative technologies of delivering audio content have emerged, with different advantages and disadvantages. In this paper pros and cons of digital audio broadcasting and webcasting transmission techniques in a network quality perspective are described. A case study of user expectations with respect to currently available services is analyzed, and the perceived quality of real digital broadcasted and webcasted radio stations is examined.

13

Quality of experience in the context of mobile applications

Nawrocki P., Śliwa A.

Computer Science

|

2016

|

Vol. 17 (3)

371--385

EN

Mobile devices are among the most-popular means of browsing the Internet, sending and receiving e-mail, and sharing content on social networks. People use mobile devices and the applications installed on them in different situations throughout the day. In order to ensure that users are satisfied with a mobile application, its author has to ensure a high Quality of Experience level. The problem of automatic evaluation of the QoE parameter is a very interesting research area. Quality of Experience is a broad issue and requires the analysis of many aspects not only graphical user interfaces but also, inter alia, Quality of Service and user ratings.

14

Subjective Assessment for Standard Television Sequences and Videotoms - H.264/AVC Video Coding Standard

Trzcianowski Ł

Journal of Telecommunications and Information Technology

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2015

|

nr 1

37--41

EN

This paper presents comparison of videotoms and standard television sequences in terms of image distortions and perceived subjective quality affected by H.264/AVC compression with changed bit rate. Results from initial tests, performed as laboratory exercise can be a reference to show scale of diversity in both level of degradation and Mean Opinion Score (MOS) evaluation. Results and comments included in this paper give overview on the codec in uence on videotoms and can suggest approach for further tests and experiments.

15

Quality Expectations of Mobile Subscribers

Gilski P., Stefański J.

Journal of Telecommunications and Information Technology

|

2015

|

nr 1

15--19

EN

Mobile systems, by nature, have finite resources. Radio spectrum is limited, expensive and shared between many users and services. Mobile broadband networks must support multiple applications of voice, video and data on a single IP-based infrastructure. These converged services each have unique traffic holding and quality requirements. A positive user experience must be obtained through efficient partitioning of the available wireless network resources. The 3rd Generation Partnership Project (3GPP) has developed a comprehensive Quality of Service (QoS) parameter to address this problem. The regular control of service quality is critical for operators to ensure user Quality of Experience (QoE), establish new business models and monetize services. It enables operators to employ fair-use resource policies and maintain network performance during peak traffic times. Wireless mobile communication is tending towards an integrated system of Internet and telecommunication technologies, where mobile users move freely anytime and everywhere. They desire to communicate with any device using the best service available. In this paper QoS management issues in mobile communication are described. The authors present an insight into subscriber behavior and related factors that affect the QoE of mobile data services.

16

Analysis of Burst Ratio in Concatenated Channels

Rachwalski J., Papier Z.

Journal of Telecommunications and Information Technology

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2015

|

nr 4

65--73

EN

Burst ratio is a parameter that quanties packet loss patterns in transmission networks. It has been dened for an end-to-end scenario, therefore burst ratio can be determined only if the characteristics of the whole transmission path are known. In this paper, the burst ratio parameter applicability to cases when the transmission path consists of a series of transmission channels with known packet loss rate and burst ratio values is extended. The paper also presents the results of simulations performed with NS2 software, demonstrating the validity of the burst ratio analysis. Consequently, the research makes it possible to determine the value of the burst ratio parameter in concatenated packet networks, which in turn supports delivering higher quality VoIP services.

17

Quality of Variable Bitrate HD Video Transmission in New Generation Access Network

Makowski P.

Journal of Telecommunications and Information Technology

|

2014

|

nr 1

21--26

EN

Article presents influence of multiplying variable bitrate high definition (HD) video streams in an access network link on Quality of Service (QoS). The aim of a conducted study is to define key parameters influencing Quality of Experience (QoE). Numerous simulations were performed and indicators like packet loss, delay, jitter, frame loss and bandwidth utilization were observed. Moreover, two independent algorithms were used to indicate QoE values of video streams. These are SwissQual VQuadHD and Telchemy VQMon applications which provided credible full reference and no reference algorithms, respectively. In the article evaluation of accuracy of no reference algorithm is performed. In future work it is planned to build analytic model of VBR video transmission and to undertake more thorough research of transmitting multiplied HD video streams in an access network using various QoS policies and optimizing size of buffers.

18

Approach to QoS/QoE monitoring and parametric model for IPTV service

Trzcianowski Ł, Kula S.

Zeszyty Naukowe. Telekomunikacja i Elektronika / Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy

|

2012

|

z. 16

41--59

EN

The main purpose of this paper is to present approach to QoS/QoE monitoring and parametric model creation for IPTV service. Monitoring system was used to perform on-line monitoring both MPEG TS parameters and subjective assessments (MOS). The second part of this work present parametric model for IPTV service, which describes relationships between single network parameters such as: jitter, packet loss, packet corrupt and throughput and subjective/objective quality measures (MOS, MSE). Created model shows influence of modified network conditions on the perceived video quality for variety vide o sequences extracted from IPTV network stream. This work also presents methodology of tests and their results which can be used to estimate the perceived quality for changes associated with modification of single network parameters.

PL

Głównym celem artykułu jest przedstawienie podejścia do monitorowania QoS/QoE i tworzenia modeli parametrycznych dla usługi IPTV. System monitorowania został użyty do monitorowania on-line parametrów (TS) MPEG i subiektywnej oceny (MOS). Druga część pracy prezentuje model parametryczny dla usług IPTV, który opisuje relacje między poszczególnymi parametrami sieciowymi, takimi jak: jitter, utrata pakietów, pakiety uszkodzone i przepustowość oraz subiektywnych/obiektywnych miar jakości (MOS, MSE). Stworzony model pokazuje wpływ zmiany warunków sieciowych na postrzeganą jakość wideo dla różnych sekwencji wideo pochodzących ze strumienia IPTV. Praca przedstawia również metodologię badań i wyniki, które można wykorzystać do oszacowania postrzeganej jakości zmian związanych z modyfikacją poszczególnych parametrów sieciowych.

19

QoE Optimized Resource Allocation in Multiuser OFDM Systems

Chen F., Qin X., Wei G.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 7b

328--331

EN

The resource allocation in multiuser Orthogonal Frequency Division Multiplexing (OFDM) systems is addressed, which aims to maximize the user-perceived quality of services instead of the conventional objective metrics. By introducing the previous application-centric Mean Opinion Score (MOS) assessment model, the problem is formulated as a bounded optimization problem, which is non-concave and difficult to develop a closed-form solution. A heuristic algorithm, which couples bound relaxation technique with further fix and drop operations is then proposed for the final solution. Simulation results indicate that our proposal can improve the overall perceived quality from users’ perspective as well as the fairness between users, in comparison with the classical throughput-oriented algorithm.

PL

Artykuł analizuje system OFDM (orthogonal frequency division multiplexing) do alokacji zasobów przy wielu użytkownikach i przesyle dużych wielkości danych. Metoda wykorzystuje serwisy QoS – Quolity of service i QoE – quality of experience.

20

The Design of an Objective Metric and Construction of a Prototype System for Monitoring Perceived Quality (QoE) of Video Sequences

Janowski L., Leszczuk M., Papir Z., Romaniak P.

Journal of Telecommunications and Information Technology

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2011

|

nr 3

87-94

EN

The paper presents different no reference (NR) objective metrics addressing the most important artefacts for raw (source) video sequences (noise, blur, exposure) and those introduced by compression (blocking, flickering) which can be used for assessing quality of experience. The validity of all metrics was verified under subjective tests.