A major cause of degradation of speech quality in HMMbased speech synthesis is the use of a simple delta pulse signal to generate the excitation of voiced speech. This paper describes a new approach to using an acoustic glottal source model in HMM-based synthesisers. The goal is to improve speech quality and parametric flexibility to better model and transform voice characteristics.

This paper describes about some speech synthesis and speech recognition algorithms and compares their performance based on accuracy and quality. In speech recognition DTW and HMM algorithms are compared with respect to accuracy. Comparative study of CELP and MBROLA algorithm of speech synthesis based on quality is also done.

We discuss techniques for Voice Activity Detection (VAD) for Voice over Internet Protocol (VoIP). VAD aids in saving bandwidth requirement of a voice session thereby increasing the bandwidth efficiently. In this paper, we compare the quality of speech, level of compression and computational complexity for three time-domain and three frequency-domain VAD algorithms. Implementation of time-domain...

The main aim of the Speech Enhancement algorithms is to improve the Quality of speech. The Quality of speech is expressed in two parameters. One is clarity, and another is intelligibility. In this paper, we proposed a method to improve the quality of speech based on computationally efficient AR modeled Iterative Kalman Filter with time and frequency mask. This approach is based on reconstructio...

Over the last decade major advances have been made in speech coding technology which is now widely used in international, digital mobile and satellite networks. The most recent techniques permit telephone network quality speech transmission at 8 kbit/s, but there are still demands for even lower rates and more flexible, good quality coding techniques for various network applications. This paper...

In this paper, the effect of MPEG audio compression on HMMbased speech synthesis is studied. Speech signals are encoded with various compression rates and analyzed using the GlottHMM vocoder. Objective evaluation results show that the vocoder parameters start to degrade from encoding with bitrates of 32 kbit/s or less, which is also confirmed by the subjective evaluation of the vocoder analysis...

In this paper, we compare and combine different approaches for instrumentally predicting the perceived quality of Text-to-Speech systems. First, a log-likelihood is determined by comparing features extracted from the synthesized speech signal with features trained on natural speech. Second, parameters are extracted which capture quality-relevant degradations of the synthesized speech signal. Bo...

We propose an algorithm to classify speech degradations at network endpoints and to estimate the speech quality based on the degradation classification decision. Perceptual features from degraded speech signals are used to form statistical reference models of different degradation classes. Consistency measures, calculated between degraded speech signals and the reference models, are used to tra...

Speech quality assessment methods are necessary for evaluating and documenting treatment outcomes of patients suffering from degraded speech due to Parkinson’s disease, stroke, or other disease processes. Subjective methods of speech quality assessment are more accurate and more robust than objective methods but are time-consuming and costly. We propose a novel objective measure of speech quali...

The quality of cleft lip and palate (CLP) speech is affected due to hyper-nasality and mis-articulation. Surgery and speech therapy are required to correct the structural and functional defects of CLP, which will result in an enhanced speech signal. The quality of the enhanced speech is perceptually evaluated by speech-language pathologists and results are highly biased. In this work, a signal ...