• Journal of the Institute of Convergence Signal Processing
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• v.2 no.4
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• pp.53-58
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• 2001

In this paper to develop objective speech quality measure for CDMA telephone network environments, recent developed measures are investigated first. But those measures show low performances in CDMA telephone networks. To solve this problem, new objective speech quality measure adopting noise masking threshold is proposed and studied. To acquire better performance, scaled noise masking threshold calculation for speech signals is employed instead of conventional tone signals. To verify effectiveness of proposed method performance comparison experiments are carried out for CDMA telephone network speech databases, for the results proposed methods show improved performances compared to existing meaures.

• Speech Sciences
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• v.6
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• pp.163-179
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• 1999

For the set up, management and repair of a mobile communication system, continuous estimation of speech quality is required. Speech quality measurement can be conducted by listener's judgement in a subjective test such as MOS (Mean Opinion Score) test. However, this method is laborious, expensive and time-consuming, it is advisable to predict subjective speech quality via objective measures. This paper presents a robust objective speech quality measure, PLP-CMS (Perceptual Linear Predictive-Cepstral Mean Subtraction), which can predict subjective speech quality in mobile communication systems. PLP-CMS has a high correlation with subjective quality owing to PLP (Perceptual Linear Predictive) analysis and shows a robust performance not being influenced by PSTN (Public Switched Telephone Network) channel effects due to CMS (Cepstral Mean Subtraction). To prove the performance of our proposed algorithm, we carried out subjective and objective quality estimation on speech samples which are variously distorted in a real mobile communication system. As a result, we demonstrated that PLP-CMS has a higher correlation with subjective quality than PSQM (Perceptual Speech Quality Measure) and PLP-CD (Perceptual Linear Predictive-Cepstral Distance).

• Phonetics and Speech Sciences
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• v.2 no.1
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• pp.71-75
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• 2010

The PESQ is an objective speech quality evaluation measure that is known to have a high correlation with a subjective speech quality measure such as MOS. To examine whether it could be useful as an objective quality measure of synthetic speech, we carried out both subjective evaluation tests with MOS and DMOS and an objective evaluation test with PESQ for HMM-based Korean synthetic speech signals and analyzed the correlation between them. Experimental results have shown that the PESQ has correlations of 0.87 with MOS and 0.92 with DMOS. It means that the PESQ holds much promise for evaluating the quality of synthetic Korean speech.

• Journal of Korea Multimedia Society
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• v.5 no.4
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• pp.405-414
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• 2002

In this paper, we propose a new objective speech quality measure using noise masking threshold for speech quality assessment of mobile telephone network environments, and verify the effectiveness of the proposed method through the experiments. For such a purpose, well known objective speech quality measures such as BSD and PSQM are first evaluated for digital mobile telephone network environments. However, these conventional methods does not have good performance under mobile networks environments compared to literary results. To be mote effective objective speech quality measure under mobile telephone environments, the proposed method employs human psychoacoustic masking effect. The DMOS, instead of MOS, is used as a subjective speech quality measure for performance evaluation. The performance comparison are carried out with speech data collected from digital mobile telephone environments. As results, the proposed measure have and average 4% higher performance, in terms of correlation, than existing objective speech quality measures such as BSD and PSQM.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.8
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• pp.881-890
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• 1992

Resonable speech quality assessment methodologies are required for speech quality assessment model which is used at speech system and communication network. There are objectlve measuies and subjective measures and subjective measure has the variousproblems in speech quality assessment methodologies. The objective of this study is to compare objective measures with subjective measure and obtain the objective measure as close as possible to subjective measure.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.10
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• pp.42-49
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• 1993

In this paper, we evaluate the quality of synthesized speech by rule using the LPC CD as a objective measure, and then compare the test result with the subjective one. Speech used for the test consists of 108 words which are selected by word construction method using Korean attribute and frequency distribution, synthesized by demi-syllable rule. By evaluating the quality of synthesized speech by reule objectively, we have tried to resolve the problems such as lots of evaluation time, expansion of test scale, and variables of analysis result arised by subjective measure. We have, also, proved the validity of the objective test using the LPC CD, by comparing intelligibility which is the index for the subjective quality evaluation of synthesized speech by rule with MOS. From this results, we can provide a guide for quality assessment that would be useful in the R&D of synthesis method and the commercial products using synthesized speech.

• Phonetics and Speech Sciences
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• v.6 no.1
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• pp.71-76
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• 2014

In this paper voice quality of normal speech is qualitatively classified by five components of breathy, creaky, rough, nasal, and thin/thick voice. To determine whether a correlation exists between a subjective measure of voice and an objective measure of voice, each voice is perceptually evaluated using the 1/2/3 scale by speech processing specialists and acoustically analyzed using speech analysis tools such as the Praat, MDVP, and VoiceSauce. The speech parameters include features related to speech source and vocal tract filter. Statistical analysis uses a two-independent-samples non-parametric test. Experimental results show that statistical analysis identified a significant correlation between the speech feature parameters and the components of voice quality.

• Proceedings of the Acoustical Society of Korea Conference
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• 1991.06a
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• pp.67-72
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• 1991

This paper evaluates thequality of synthesized speech by rule using the LPC CD in the objective measure and then compares the result with the subjective analysis. By evaluating the quality of synthesized speech by rule objectively. We have tried to resolve the problems (Evaluation time or size expansion, variables within the analysis results) that arise when the evaluation is done subjectively. Also by comparing intelligibility-the index for the subjective quality evaluation of synthesized speech by rule-with evaluation results obtained using MOS and the objective evaluation. We have proved the validity of the objective analysis and thus provides a guide that would be useful when R&D and marketing of synthesis by rule method is done.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06e
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• pp.297-302
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• 1998

본 논문에서는 CDMA(Code Division Multiple Access) 채널을 통과하면서 여러 가지 형태로 손상된 음성에 대한 주관적 음질 평가를 할 수 있는 객관적 척도에 대한 연구를 수행하였다. 즉, CDMA 채널을 통과한 음성 신호에 대하여 주관적 음질 평가 방법 중 가장 많이 사용되고 있는 MOS(Mean Opinion Score) 테스트를 수행하고, 이 MOS 테스트 결과를 추정할 수 있는 객관척도 알고리즘을 시뮬레이션 하였다. 이러한 연구 결과로 PSQM(Perceptual Speech Quality Measure)을 CDMA 채널 환경에 맞게 수정하여 우수한 성능의 객관적 음질 평가 방법을 얻었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.4B
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• pp.437-446
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• 2001

음질 평가에는 주관적 음질 평가법과 객관적 음질 평가법이 있는데, 주관적 음질 평가법은 사람이 직접 듣고 평가하므로 실제 체감 음질을 나타낸다. 그러나 많은 사람들에 의하여 직접 평가되므로 비용과 시간이 많이 소모되는 단점이 있다. 객관적 음질 평가법은 수학적인 계산에 의하여 원음과 왜곡음의 유사성을 비교하는 것으로 빠르고 비용이 적게 되나 실제 체감 음질과는 거리과 있다. 본 논문에서는 객관적 음질 평가 척도로 BCF(Bark Coherence Function)을 제안한다. BCF는 심리 음향 영역에서 코히어런스 함수를 정의한 것으로 기존의 객관적 음질 평가법에 비하여 주관적 음질과 상관관계가 높고 계산량이 적다. CDMA 이동 전화 시스템의 음성 데이터와 회기분석 결과, BCF가 ITU-T 표준안의 PSQM(Perceptual Speech Quality Measure)와 MNB(Measuring Normalizing Block)에 비하여 높은 상관관계를 갖음을 입증하였다.