Objective and Subjective Evaluation of Wideband Speech Quality - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Objective and Subjective Evaluation of Wideband Speech Quality write by Nazanin Pourmand. This book was released on 2012. Objective and Subjective Evaluation of Wideband Speech Quality available in PDF, EPUB and Kindle. Traditional landline and cellular communications use a bandwidth of 300 - 3400 Hz for transmitting speech. This narrow bandwidth impacts quality, intelligibility and naturalness of transmitted speech. There is an impending change within the telecommunication industry towards using wider bandwidth speech, but the enlarged bandwidth also introduces a few challenges in speech processing. Echo and noise are two challenging issues in wideband telephony, due to increased perceptual sensitivity by users. Subjective and/or objective measurements of speech quality are important in benchmarking speech processing algorithms and evaluating the effect of parameters like noise, echo, and delay in wideband telephony. Subjective measures include ratings of speech quality by listeners, whereas objective measures compute a metric based on the reference and degraded speech samples. While subjective quality ratings are the "gold - standard'', they are also time- and resource- consuming. An objective metric that correlates highly with subjective data is attractive, as it can act as a substitute for subjective quality scores in gauging the performance of different algorithms and devices. This thesis reports results from a series of experiments on subjective and objective speech quality evaluation for wideband telephony applications. First, a custom wideband noise reduction database was created that contained speech samples corrupted by different background noises at different signal to noise ratios (SNRs) and processed by six different noise reduction algorithms. Comprehensive subjective evaluation of this database revealed an interaction between the algorithm performance, noise type and SNR. Several auditory-based objective metrics such as the Loudness Pattern Distortion (LPD) measure based on the Moore - Glasberg auditory model were evaluated in predicting the subjective scores. In addition, the performance of Bayesian Multivariate Regression Splines(BMLS) was also evaluated in terms of mapping the scores calculated by the objective metrics to the true quality scores. The combination of LPD and BMLS resulted in high correlation with the subjective scores and was used as a substitution for fine - tuning the noise reduction algorithms. Second, the effect of echo and delay on the wideband speech was evaluated in both listening and conversational context, through both subjective and objective measures. A database containing speech samples corrupted by echo with different delay and frequency response characteristics was created, and was later used to collect subjective quality ratings. The LPD - BMLS objective metric was then validated using the subjective scores. Third, to evaluate the effect of echo and delay in conversational context, a realtime simulator was developed. Pairs of subjects conversed over the simulated system and rated the quality of their conversations which were degraded by different amount of echo and delay. The quality scores were analysed and LPD+BMLS combination was found to be effective in predicting subjective impressions of quality for condition-averaged data.
Research on Objective Speech Quality Measurements
Research on Objective Speech Quality Measurements - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Research on Objective Speech Quality Measurements write by Carol S. Chow. This book was released on 2001. Research on Objective Speech Quality Measurements available in PDF, EPUB and Kindle.
Speech Quality of VoIP
Speech Quality of VoIP - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Speech Quality of VoIP write by Alexander Raake. This book was released on 2007-01-11. Speech Quality of VoIP available in PDF, EPUB and Kindle. Finally a comprehensive overview of speech quality in VoIP from the user's perspective! Speech Quality of VoIP is an essential guide to assessing the speech quality of VoIP networks, whilst addressing the implications for the design of VoIP networks and systems. This book bridges the gap between the technical network-world and the psychoacoustic world of quality perception. Alexander Raake’s unique perspective combines awareness of the technical characteristics of VoIP networks and original research concerning the perception of speech transmitted across them. Starting from the network designer’s point of view, the different characteristics of the network are addressed, and then linked to features perceived by users. This book provides an overview of the available knowledge on the principal, relevant aspects of speech and speech quality perception, of speech quality assessment, and of transmission properties of telephone and VoIP networks, and of the related perceptual features and resulting speech quality. Discussing new research into the specific time-varying degradations VoIP brings along, but also the considerable potential of quality improvement to be achieved with wideband speech transmission, Alexander Raake demonstrates how network and service characteristics impact on the users perception of quality. Speech Quality of VoIP: Offers an insight into speech quality of VoIP from a user's perspective. Presents an overview of different modelling approaches and a parametric network-planning model for quality prediction in VoIP networks. Draws on innovative new research on the quality degradation characteristic of VoIP. Explains in detail how telephone speech quality can be greatly enhanced with VoIP’s wideband speech transmission capability. Assesses the vast collection of references into the technical and scientific literature related to VoIP quality. Illustrates concepts throughout with mathematical models, algorithms and simulations. Speech Quality of VoIP is the definitive guide for researchers, engineers and network planners working in the field of VoIP, Quality of Service, and speech communication processing in telecommunications. Advanced undergraduate and graduate students on telecommunication and networking courses will also find this text an invaluable resource.
Subjective Quality Measurement of Speech
Subjective Quality Measurement of Speech - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Subjective Quality Measurement of Speech write by Kazuhiro Kondo. This book was released on 2012-02-09. Subjective Quality Measurement of Speech available in PDF, EPUB and Kindle. It is becoming crucial to accurately estimate and monitor speech quality in various ambient environments to guarantee high quality speech communication. This practical hands-on book shows speech intelligibility measurement methods so that the readers can start measuring or estimating speech intelligibility of their own system. The book also introduces subjective and objective speech quality measures, and describes in detail speech intelligibility measurement methods. It introduces a diagnostic rhyme test which uses rhyming word-pairs, and includes: An investigation into the effect of word familiarity on speech intelligibility. Speech intelligibility measurement of localized speech in virtual 3-D acoustic space using the rhyme test. Estimation of speech intelligibility using objective measures, including the ITU standard PESQ measures, and automatic speech recognizers.
Perceptual Audio Evaluation - Theory, Method and Application
Perceptual Audio Evaluation - Theory, Method and Application - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Perceptual Audio Evaluation - Theory, Method and Application write by Søren Bech. This book was released on 2007-01-11. Perceptual Audio Evaluation - Theory, Method and Application available in PDF, EPUB and Kindle. As audio and telecommunication technologies develop, there is an increasing need to evaluate the technical and perceptual performance of these innovations. A growing number of new technologies (e.g. low bit-rate coding) are based on specific properties of the auditory system, which are often highly non-linear. This means that the auditory quality of such systems cannot be measured by traditional physical measures (such as distortion, frequency response etc.), but only by perceptual evaluations in the form of listening tests. Perceptual Audio Evaluation provides a comprehensive guide to the many variables that need to be considered before, during and after experiments. Including the selection of the content of the programme material to be reproduced, technical aspects of the production of the programme material, the experimental set-up including calibration, and the statistical planning of the experiment and subsequent analysis of the data. Perceptual Audio Evaluation: Provides a complete and accessible guide to the motives, theory and practical application of perceptual evaluation of reproduced sound. Discusses all the variables of perceptual evaluation, their control and their possible influence on the results. Covers in detail all international standards on the topic. Is illustrated throughout with tables, figures and worked solutions. Perceptual Audio Evaluation will appeal to audio and speech engineers as well as researchers in audio and speech laboratories. Postgraduate students in engineering or acoustics and undergraduate students studying psychoacoustics, speech audio processing and signal processing will also find this an essential reference.
