University of Zilina
Telecommunications and Multimedia
This paper investigates an impact of independent and dependent losses and coding on speech quality predictions provided by PESQ and P.563, when both naturally-produced and synthesized speech are transmitted over various channels. Two... more
This paper investigates an impact of independent and dependent losses and coding on speech quality predictions provided by PESQ and P.563, when both naturally-produced and synthesized speech are transmitted over various channels. Two synthesized speech signals generated with two different Text-to-Speech systems and one naturallyproduced signal are investigated. In addition, we assess the variability of PESQ’s and P.563’s predictions with respect to type of signal used (naturally-produced or synthesized) and loss conditions. The results show that the synthesized speech suffers more from packet loss than the naturally-produced speech which also results in the bigger predictions deviations for such type of speech. On the other hand, the impact of ‘artificially’ sounding codecs is higher for the naturally-produced speech. In contrast to previous codec type, the quality predictions for ‘natural’ sounding codec are -with the exception of the predictions provided by P.563 model- very simil...
This paper deals with measurements of the impact of background traffic on video quality in WLAN (IEEE 802.11b) environment.
Nowadays, health application has growing market potential. In this paper, an investigation of electro-conductive, parameters of blended silver coated polyamide yarn were measured. We focused on the several objectives important in... more
Nowadays, health application has growing market potential. In this paper, an investigation of electro-conductive, parameters of blended silver coated polyamide yarn were measured. We focused on the several objectives important in electro-conductive yarns design and application into intelligent clothing. In detail, the effect of num bers of silver filaments, draft and twists, the effect of external heating source on electrical and temperature parameters were tested. Likewise, the possibilities of electro-conductive yarn as data bus were tested too.
- by Robert Hudec and +1
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- Elektro
In this paper a comparison between two popular feature extraction methods is presented. Scale-invariant feature transform (or SIFT) is the first method. The Speeded up robust features (or SURF) is presented as second. These two methods... more
In this paper a comparison between two popular feature extraction methods is presented. Scale-invariant feature transform (or SIFT) is the first method. The Speeded up robust features (or SURF) is presented as second. These two methods are tested on set of depth maps. Ten defined gestures of left hand are in these depth maps. The Microsoft Kinect camera is used for capturing the images [1]. The Support vector machine (or SVM) is used as classification method. The results are accuracy of SVM prediction on selected images.
- by Robert Hudec
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- Kinect, Surf, SIFT, Svm
The texture feature extraction plays important role in image analysis. This paper deals with improvement of the one-dimensional version of GLCM (Gray Level Cooccurrence Matrix). In our approach, the color information of texture was taken... more
The texture feature extraction plays important role in image analysis. This paper deals with improvement of the one-dimensional version of GLCM (Gray Level Cooccurrence Matrix). In our approach, the color information of texture was taken into consideration. The novel One dimensional Color Level Co-occurrence Matrix (1D-CLCM) are designed. Performances of proposed method are verified on database of 2600 color images. Experimental results demonstrated that 1D-CLCM is more effective compared to one-dimensional and original GLCM for image retrieval.
This document describes the simulations in transmission chain. The aim of simulations was to obtain optimal testing signal determined for automatic intrusive measurement VTQoS (Voice Transmission Quality of Service). Evaluation of... more
This document describes the simulations in transmission chain. The aim of simulations was to obtain optimal testing signal determined for automatic intrusive measurement VTQoS (Voice Transmission Quality of Service). Evaluation of simulation signal was based on calculation of mean square measure and correlation coefficient. Suitable signals of beforehand defined group were chosen on the basis of these parameters. Suitable signals will be used to create resulting test sequence.
- by Peter Pocta and +1
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This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks... more
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech... more
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech quality estimation in simulated VoIP environment. These two reference signal characteristics are defined very broadly by ITU-T Recommendation P.862.3. That is reason to investigate an impact of those characteristics on speech quality estimation more in depth. We assess the variability of PESQ estimations with respect to the reference signal characteristics and network conditions and finally offer some proposals for the purpose of more accurate and reliable speech quality assessment from those reference signal characteristics point of view in IP networks.
This paper describes simulations of test and speech sequences transmission for intrusive measurement of Voice Transmission Quality of Service (VTQoS) in the environment of IP networks. The aim of simulations was detect environment... more
This paper describes simulations of test and speech sequences transmission for intrusive measurement of Voice Transmission Quality of Service (VTQoS) in the environment of IP networks. The aim of simulations was detect environment influences on the quality of transmission sequences, particularly an influence of coding schemes, packets loss and the jitter on the transmission sequences. The evaluation of test and speech sequences simulations were based on the calculation of the mean square measure. Reconsideration of a convenience of the given test sequence, which is composed from simple signals, on intrusive measurement of VTQoS in the environment of IP networks is the aim of this paper.
- by Peter Pocta and +1
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This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as... more
This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service and Web service. The background traffic was generated by means of the accomplished D -ITG traffic generator. The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished PESQ algorithm. The proposal of a new method of improved detection of the critical conditions in telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of the critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of IP networks. The primary goal of these algorithms is improving speech quality in the VoIP connections, which are established in the competent link.
This paper describes simulations of speech sequences transmission for intrusive measurement of voice transmission quality of service (VTQoS) in the environment of IP networks. The aim of the simulations was to investigate the impact of... more
This paper describes simulations of speech sequences transmission for intrusive measurement of voice transmission quality of service (VTQoS) in the environment of IP networks. The aim of the simulations was to investigate the impact of the different durations of speech sequences on speech quality from the jitter rate and packet loss point of view in IP networks. The ITU-T G.729 and ITU-T G.723.1 encoding schemes were used for the purpose of the simulations. The assessment of speech quality was realized by means of perceptual evaluation of speech quality (PESQ) algorithm. A comparison of the impact of different durations of speech sequences on speech quality and determination of the optimal duration of speech sequence for measurements of speech quality in telecommunication networks, is the aim of this paper.
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks... more
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
This paper describes simulations of a test sequence transmission for intrusive measurement of VTQoS in mobile environment. The aim of the simulation was to analyze an influence of multipath signals propagation and propagation attenuation... more
This paper describes simulations of a test sequence transmission for intrusive measurement of VTQoS in mobile environment. The aim of the simulation was to analyze an influence of multipath signals propagation and propagation attenuation on the test sequence. Evaluation the generated sequences was based on the calculation of mean square measure and correlation coefficient. These measures were used as a criterion for suitable test sequences selection. Reconsideration of an influence of mobile environment on the test sequences, which are composed from simple signals, is the aim of this paper.
- by Martin Vaculík and +1
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- Correlation coefficient
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks... more
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of WLANs. The primary goal of these algorithms is improving speech quality in the VoWLAN connections, which are established in the competent link.
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech... more
In this work, we experimentally study how behaviour of the PESQ-estimate varies with reference signal characteristics. In particular we investigate the impact of different lengths of reference signal and active speech ratios on speech quality estimation in simulated VoIP environment. These two reference signal characteristics are defined very broadly by ITU-T Recommendation P.862.3. That is reason to investigate an impact of those characteristics on speech quality estimation more in depth. We assess the variability of PESQ estimations with respect to the reference signal characteristics and network conditions and finally offer some proposals for the purpose of more accurate and reliable speech quality assessment from those reference signal characteristics point of view in IP networks.
This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as... more
This paper describes measurements of an impact of background traffic on speech quality in an environment of IP networks. The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service and Web service. The background traffic was generated by means of the accomplished D -ITG traffic generator. The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished PESQ algorithm. The proposal of a new method of improved detection of the critical conditions in telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of the critical conditions for the purpose of algorithms for link adaptation from the speech quality point of view in an environment of IP networks. The primary goal of these algorithms is improving speech quality in the VoIP connections, which are established in the competent link.
Special kind of genetic algorithm – eugenic algorithm is presented for constructing minimum-cost tree with delay constraints. Telecommunication network is represented by undirected graph, which uses three independent metrics: cost, delay... more
Special kind of genetic algorithm – eugenic algorithm is presented for constructing minimum-cost tree with delay constraints. Telecommunication network is represented by undirected graph, which uses three independent metrics: cost, delay and capacity. The efficiency of two different bit representations of individuals (adjacent matrix, list of vertices) is compared.
- by Peter Kortiš
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A special kind of genetic algorithm – eugenic algorithm is presented for constructing minimum-cost tree with delay constraints. Telecommunication network is represented by an undirected graph, which uses three independent metrics: cost,... more
A special kind of genetic algorithm – eugenic algorithm is presented for constructing minimum-cost tree with delay constraints. Telecommunication network is represented by an undirected graph, which uses three independent metrics: cost, delay and capacity. The efficiency of two different bit representations of individuals (adjacent matrix, list of vertices) is compared.
- by Peter Kortiš
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This contribution deals with routing of Multipoint connections in telecommunication networks using Eugenic algorithm. Telecommunication network is represented by undirected graph. Proposed algorithm uses matrix bit representation of... more
This contribution deals with routing of Multipoint connections in telecommunication networks using Eugenic algorithm. Telecommunication network is represented by undirected graph. Proposed algorithm uses matrix bit representation of individual.
- by Peter Kortiš
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This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks... more
This paper describes measurements of the impact of background traffic on speech quality in an environment of WLANs (IEEE 802.11). The simulated background traffic consists of three types of current traffics in telecommunication networks such as data transfer service, multimedia streaming service, and Web service. The background traffic was generated by means of the accomplished Distributed Internet Traffic Generator (D-ITG). The impact of these types of traffic and traffic load on speech quality using the test sequence and speech sequences is the aim of this paper. The assessment of speech quality is carried out by means of the accomplished Perceptual Evaluation of Speech Quality (PESQ) algorithm. The proposal of a new method for improved detection of the critical conditions in wireless telecommunication networks from the speech quality point of view is presented in this paper. Conclusion implies the next application of the method of improved detection of critical conditions for the...