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Analiza jakości szyfrowanej komunikacji VoIP communication quality in limiting radio receiver sensitivity conditions

Polak Rafał, Wojtuń Jarosław, Łubkowski Piotr

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2022

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nr 4

215--218

PL

Zasadniczym wyzwaniem związanym z realizacją współczesnych usług komunikacji multimedialnej jest zapewnienie wysokiego poziomu bezpieczeństwa, wysokiej dostępności i wysokiej jakości usług w zróżnicowanym heterogenicznym środowisku sieciowym. Implementacja dowolnego algorytmu szyfrowania może skutkować zasadniczym pogorszeniem jakości zwłaszcza w warunkach pogorszenia parametrów kanału radiowego. Zjawisko to jest szczególnie często obserwowane na granicy czułości odbiornika. W artykule przedstawiono metodykę i wyniki badania wpływu szyfrowania SCIP na jakość komunikacji VoIP w szerokopasmowym kanale radiowym w granicznych warunkach czułości odbiornika radiowego. Pomiary przeprowadzono za pomocą testera MultiDSLA oraz metod PESQ i POLQA.

EN

The main challenge associated with the implementation of modern multimedia communication services is to ensure a high level of security, high availability and high-quality services in the heterogenous network environment. Implementation of any encryption algorithm may lead to a deterioration of quality especially in the radio communication networks due to changes in the radio channel parameters. This phenomenon is particularly often observed at the sensitivity limit of the radio channel. The article presents the methodology and results of the study of the impact of SCIP encryption, on the quality of VoIP communication in in a wideband radio channel in limiting condition of channel sensitivity. The measurements were performed using the MultiDSLA tester and the PESQ and POLQA methods.

2

Perceptual Identification of Polish Vowels Due to F0 Changes

Owsianny Mariusz

Archives of Acoustics

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2019

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Vol. 44, No. 1

13--26

EN

The paper investigates the interdependence between the perceptual identification of the vocalic quality of six isolated Polish vowels traditionally defined by the spectral envelope and the fundamental frequency F0. The stimuli used in the listening experiments were natural female and male voices, which were modified by changing the F0 values in the ±1 octave range. The results were then compared with the outcome of the experiments on fully synthetic voices. Despite the differences in the generation of the investigated stimuli and their technical quality, consistent results were obtained. They confirmed the findings that in the perceptual identification of vowels of key importance is not only the position of the formants on the F1 × F2 plane but also their relationship to F0, the connection between the formants and the harmonics and other factors. The paper presents, in quantitative terms, all possible kinds of perceptual shifts of Polish vowels from one phonetic category to another in the function of voice pitch. An additional perceptual experiment was also conducted to check a broader range of F0 changes and their impact on the identification of vowels in CVC (consonant, vowel, consonant) structures. A mismatch between the formants and the glottal tone value can lead to a change in phonetic category.

3

Acoustic Parameters in the Evaluation of Voice Quality of Choral Singers. Prototype of Mobile Application for Voice Quality Evaluation

Szklanny Krzysztof

Archives of Acoustics

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2019

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Vol. 44, No. 3

439--446

EN

Choral singers are among intensive voice users whose excessive vocal effort puts them at risk of developing voice disorders. The aim of the work was to assess voice quality for choral singers in the choir at the Polish-Japanese Academy of Information Technology. This evaluation was carried out using the acoustic parameters from the COVAREP (A Collaborative Voice Analysis Repository For Speech Technologies) repository. A prototype of a mobile application was also prepared to allow the calculation of these parameters. The study group comprised 6 male and 19 female choir singers. The control group consisted of health non-singing individuals, 50 men and 39 women. Auditory perceptual assessment (using the RBH scale) as well as acoustic analysis were used to test the voice quality of all the participants. The voice quality of the female choir singers proved to be normal in comparison with the control group. The male choir singers were found to have tense voice in comparison with the controls. The parameters which proved most effective for voice evaluation were Peak Slope and Normalized Amplitude Quotient.

4

Comparison of singing voice quality from the beginning of the phonation and in the stable phase in the case of choral voices

Półrolniczak Edward, Kramarczyk Michał

Annals of Computer Science and Information Systems

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2019

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Vol. 18

349–-353

EN

In the process of acoustic voice analysis, in this case of singing, it is important that the sound samples contain a stable phase of phonation. Sometimes, however, it is not possible. This study was prepared to determine how big are the differences between the values of the acoustic parameters obtained for the initial phase of phonation and for the stable phase of phonation. The values of acoustic parameters, such as, among others shimmer, jitter, RAP, PPQ, APQ, HNR or SPR were estimated for registered singing samples in the initial phase of phonation and in the middle phase. The analysis were performed over the samples of singing of the vowel 'a' recorded many times for different pitches. In the process of analyzing of the obtained results, it was found that the impact of the selection phase of phonation for analysis is crucial in assessing the singing voice quality.

5

Badania łącza internetowego do transmisji głosu (VOIP)

Pniewski M.

Prace Naukowe Politechniki Śląskiej. Elektryka

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2011

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z. 2

113-125

PL

W artykule została przedstawiona analiza przeprowadzonych badań praktycznych, dotyczących jakości połączeń głosowych z wykorzystaniem sieci pakietowych oraz zostały podane przykłady metod, mogących służyć do oceny jakości łącza internetowego. Zaprezentowano przykładowe metody oceny jakości głosu, ich klasyfikację oraz sposoby pomiaru parametrów charakteryzujących jakość usługi. Uwzględniono zarówno metody profesjonalne, takie jak pomiar MOS (ang. Mean Opinion Score) za pomocą P.862 i algorytmu PESQ (ang. Perceptual Evaluation of Speech Quality), jak i metody dostępne dla użytkownika domowego. Przedstawiono środowisko testowe do badań jakości głosu. Pozwalało ono na zbadanie wpływu parametrów łącza internetowego, takich jak przepustowość, straty pakietów oraz opóźnienie.

EN

The article presents an analysis of the practical examinations of the quality of voice calls using the packet network and there are examples of methods that can be used to evaluate the quality of the Internet connection. Some exemplary methods for evaluate voice quality, their classification and methods of measurement of parameters characterizing the quality of service. It reflects also the professional methods, such as measurement of MOS (Mean Opinion Score) with P.862 PESQ algorithm and (Perceptual Evaluation of Speech Quality) and the methods available for the home user. Presents the test environment to test voice quality. This allowed it to examine the impact of Internet connection parameters such as throughput, packet loss and delay.

6

Metody oceny jakości dźwięku w telefonii voice over IP

Apiecionek Łukasz

Studia i Materiały Informatyki Stosowanej

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2010

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nr 3

13--20

PL

Algorytmy oceny jakości dźwięku pracują z sygnałem wzorcowym bądź bez niego. Metody charakteryzują się różnymi wymaganiami na moc obliczeniową procesora oraz pamięć danych. Determinuje to możliwość zastosowania metod w trybie monitorowania stanu pracy sieci VoIP. Niniejszy artykuł przedstawia opis metod oceny jakości dźwięku, które można próbować zastosować dla telefonii VoIP.

EN

Voice quality measurement algorithms could work with or without reference signal. They have different needs for CPU performance and data memory. This needs could disturb possibility of using algorithms in real VoIP network. This paper contains descriptions of quality measurement algorithms in case of using its in VoIP networks.

7

Feature space reduction and classification in automatic voice quality estimation

Samborska A.

Image Processing & Communications

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2005

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Vol. 10, no 2

93-102

EN

The paper presents an approach to solve a problem of feature space reduction applied to a voice quality estimation system. In order to reduce symptom space dimensionality, a method based on of decision tree and Fisher Linear Discriminant has been introduced. On the basis of 3 discrimination tests, the patient's voice is being classified into one of 3 groups - healthy, ill or risk, obtaining 90% of correct results. The experiment involved voice recordings of 70 patients who were diagnosed by the specialist. The method has been applied to a system of automatic voice quality estimation - the SpeechAnalyser, which was designed to be a supportive tool in laryngologica. l screening tests and treatment progress monitoring. There have been also briefly introduced the algorithms of feature extraction from a voice sample and also diagnostic significance of the symptoms has been discussed. Author proposed a new approach to cepstral analysis that allows objective measuring of harmonic and subharmonic content is spectrum.