This paper presents an experimental comparison of a broad range of the leading vocoder types which have been previously described. We use a reference implementation of each of these to create stimuli for a listening test using copy synthesis. The listening test is performed using both Lombard and normal read speech stimuli, and with two types of question for comparison. Multi-dimensional Scalin...

Title of Thesis : AN ALGORITHM TO EVALUATE THE ECHO SIGNAL AND THE VOICE QUALITY IN VOIP NETWORKS Andre Neumann Kauffman, M.S., 2006 Directed By: Associate Professor, Steven A. Tretter, Department of Electrical and Computer Engineering Voice over the Internet Protocol (VoIP) has been increasingly popular, but reliability and voice quality remain important factors that limit the widespread adopt...

Speech Enhancement is a challenging and important area of research due to the many applications that depend on improved signal quality. It is a pre-processing step of speech processing systems and used for perceptually improving quality of speech for humans. With recent advances in Deep Neural Networks (DNN), deep Denoising Auto-Encoders have proved to be very successful for speech enhancement....

In this paper, we investigate a long state vector Kalman filter for the enhancement of speech that has been corrupted by white and coloured noise. It has been reported in previous studies that a vector Kalman filter achieves better enhancement than the scalar Kalman filter and it is expected that by increasing the state vector length, one may improve the enhancement performance even further. Ho...

In mobile devices, perceived speech signal degrades significantly in the presence of background noise as it reaches directly at the listener's ears. There is a need to improve the intelligibility and quality of the received speech signal in noisy environments by incorporating speech enhancement algorithms. This paper focuses on speech enhancement method including auditory masking propertie...

In this paper, we consider single-channel speech enhancement in the short time Fourier transform (STFT) domain. We suggest to improve an STFT phase estimate by estimating the initial phases. The method is based on the harmonic model and a model for the phase evolution over time. The initial phases are estimated by setting up a least squares problem between the noisy phase and the model for phas...

In many hands-free applications, we encounter a speaker located in the near-field embedded in diffuse far-field noise. In this paper, we contribute an algorithm to estimate the speech and noise power spectral density (PSD) based on a directiondependent SNR (DD-SNR). The only prior knowledge needed is a model of the diffuse noise sound field. The enhanced speech signal is obtained by a parametri...

In this paper we have carried out an accurate overview on Voice over IP QoS evaluation techniques. We have described in a detailed way the most important measurement methods that are subdivided in subjective and objective methods. Subjective measurements (e.g. Mean Opinion Score MOS) are the benchmark for objective methods, but they are slow, time consuming and expensive. Objective measurements...

The use of simultaneous masking in speech enhancement has shown promise for a range of noise types. In this paper, a new speech enhancement algorithm based on a short-term temporal masking threshold to noise ratio (MNR) is presented. A novel functional model for forward masking based on three parameters is incorporated into a speech enhancement framework based on speech boosting. The performanc...

Voice quality assessment is an emergent aspect in Global System for Mobile Communications (GSM) network. The evolution of GSM also able in principle to take benefit from end to end services.GSM network inherently include elements such as noisy intermediate equipments that degrade the quality of transmitted voice signal.GSM network presents an alternate method to improve quality and customer exp...