The DYPSA algorithm for estimation of glottal closure instants in voiced speech

556

288

Abstract-Epoch is the instant of significant excitation of the vocal-tract system during production of speech. For most voiced speech, the most significant excitation takes place around the instant of glottal closure. Extraction of epochs from speech is a challenging task due to time-varying characteristics of the source and the system. Most epoch extraction methods attempt to remove the characteristics of the vocal-tract system, in order to emphasize the excitation characteristics in the residual. The performance of such methods depends critically on our ability to model the system. In this paper, we propose a method for epoch extraction which does not depend critically on characteristics of the time-varying vocaltract system. The method exploits the nature of impulse-like excitation. The proposed zero resonance frequency filter output brings out the epoch locations with high accuracy and reliability. The performance of the method is demonstrated using CMU-Arctic database using the epoch information from the electro-glottograph as reference. The proposed method performs significantly better than the other methods currently available for epoch extraction. The interesting part of the results is that the epoch extraction by the proposed method seems to be robust against degradations like white noise, babble, high-frequency channel, and vehicle noise.

Section: B Review Of the Existing Methodsmentioning

confidence: 99%

Epoch Extraction From Speech Signals

Murty

Yegnanarayana

2008

556

288

“…Additionally, due to the propagation time between the EGG and the waveform, the reference GCIs and the detected GCIs are synchronized for each utterance by maximizing their correlation. Four methods are compared: the proposed method using MSP, the previously proposed method using a Glottal Shape estimate (GCIGS) [39], the DYPSA method [14] and another method based on Group-Delay (GD) [15], [18]. Figure 4 shows the evaluation results on three CMU Arctic databases [40].…”

Section: ) Evaluation Of Gci Estimatesmentioning

confidence: 99%

“…In terms of phase, the better the estimate of the model, the smaller the phase spectrum of the convolutive residual. This criterion has already been proposed to estimate Glottal Closure Instants (GCI) resulting in robust estimators [14], [15]. In these methods, assuming the source is a Dirac delta and the VTF is an all-pole filter, the phase spectrum of an LP residual is minimized.…”

Section: Introductionmentioning

confidence: 99%

Phase Minimization for Glottal Model Estimation

Degottex

Röebel

Rodet

2011

Abstract-In glottal source analysis, the phase minimization criterion has already been proposed to detect excitation instants. As shown in this article, this criterion can also be used to estimate the shape parameter of a glottal model (ex. LiljencrantsFant model) and not only its time position. Additionally, we show that the shape parameter can be estimated independently of the glottal model position. The reliability of the proposed methods is evaluated with synthetic signals and compared to that of the IAIF and minimum/maximum-phase decomposition methods. The results of the methods are evaluated according to the influence of the fundamental frequency and noise. The estimation of a glottal model is useful for the separation of the glottal source and the vocal-tract filter and therefore can be applied in voice transformation, synthesis and also in clinical context or for the study of the voice production.

“…The pitch deviation cost is a function of the current and previous two GCI candidates under consideration by the DP and is defined as (12) where the pitch deviation is (13) The cost increases nonlinearly with from 0.5 to 0.5, applying relatively small penalties for minor pitch changes based on an assumption of smooth variation in pitch over short segments of voiced speech. The rate of increase of cost with pitch deviation is controlled by and zero cost is obtained at (14) In our experiments, has been employed so as to obtain zero cost at pitch deviation of 25%.…”

Section: ) Pitch Deviation Costmentioning

confidence: 99%

“…We also briefly discuss approaches to estimate GOIs. An earlier version of the DYPSA algorithm was outlined in [13].…”

Section: Introductionmentioning

confidence: 99%

Estimation of Glottal Closure Instants in Voiced Speech Using the DYPSA Algorithm

Naylor

Kounoudes

Guðnason

et al. 2007

Self Cite

288

218

Abstract-We present the Dynamic Programming Projected Phase-Slope Algorithm (DYPSA) for automatic estimation of glottal closure instants (GCIs) in voiced speech. Accurate estimation of GCIs is an important tool that can be applied to a wide range of speech processing tasks including speech analysis, synthesis and coding. DYPSA is automatic and operates using the speech signal alone without the need for an EGG signal. The algorithm employs the phase-slope function and a novel phase-slope projection technique for estimating GCI candidates from the speech signal. The most likely candidates are then selected using a dynamic programming technique to minimize a cost function that we define. We review and evaluate three existing methods of GCI estimation and compare the new DYPSA algorithm to them. Results are presented for the APLAWD and SAM databases for which 95.7% and 93.1% of GCIs are correctly identified.