Search

The combination of Vector Quantization (VQ) and predictive techniques -named AVPC systems- has been shown as interesting systems for speech waveform coding at medium-high rates (ref. 1 to 3). In this work we present a such system including a previous four subbbands splitting. This allows good quality of speech at low-medium rates (1-1.25 bits/sample). A comparative study show that the AVPC-SBC outperforms the simple AVPC coder.

This paper presents an algorithm that provides a syllabic segmentation of speech following the syllabification rules of Spanish language. The implemented algorithm is divided into two parts. First, an initial segmentation is made based on energy contour, sonority and duration. Second, a fine adjustement of syllable boundaries and final segmentation is made by applying syllabic rules.

This communication reports the use of demisyllables for continuous speech recognition in a specific application: the recognition of Spanish numbers. After a brief outline of the recognition system, a description of demisyllable syntactic constraints and one-speaker reference generation is provided. Finally, the recognition performance is assessed by means of two experiments: the recognition of integer numbers from zero to one thousand and telephone numbers uttered in a Spanish way (strings of integers from zero to ninety nine), in both applications the results that the system yielded were excellent.

Vector quantization (VQ) is a simultaneous quantization of a sequence of samples or vector. This process allows to malee effective use of the interrelations among the different vector components and performance arbitrarily close to the ultimate rate-distortion can be achieved by VQ if the vector dimension is high enough. Nevertheless, the exponential growth in complexity forces the use of low -dimensionality VQ in practica! systems. In this case sorne kind of adaptation is necessary to obtain adequate performance. Adaptive Multistage VQ (AMSVQ) [1] is a simple method that allows to redesign the quantizer as it is used, thus increasing its robustness and performance. In this paper, it is shown the close relation between the proposed adaptation algorithm and the methods usually employed to design the vector quantizers. Then sorne results are presented in which the AMSVQ reduce the complexity and improve the performance of previous VQ-based schemes of quantizing the LPC parameters.

The use of an orthogonal expansion for feature selection and data compression in isolated word recognition is presented. Assuming that the spectral evolution, given by a LPC analysis, is a noisy measure in the sense that it is a linear combination of a set of real features, the objective of the orthogonal expansion is to find these real features. The new feature vectors are used to perform the recognition process. The recognition results as well as the meaning of the orthogonal expansion are discussed

Guía de la flora de Parla estructurada en dos partes: la primera, titulada 'Guía didáctica de los árboles' y una segunda con el nombre de 'Los árboles de Parla'. La guía didáctica pretende ser un esquema con las posibles formas de acercamiento al estudio de los árboles y a las características más importantes de cada especie. La segunda parte, presenta el resultado obtenido tras la recogida de muestras de los árboles de las plazas, calles y colegios de Parla. Incluye al final del libro, un glosario con términos de uso botánico más frecuentes. Madrid ESP

Envelope and instantaneous phase of a real signal are two concepts mainly associated with modulation systems. In this paper is shown how envelope and lnstantaneous phase can be applied in coding systems. In particular, the envelope of t he residual provides informatton ahnut pitch ilnd energy of the signal and can be user to properly codify it. A parametric version of the envelope is taken from the residual of a s ignal and this informat ion ls used ln two different coders: an APC corleranda stochastlcally excited coder. In APC coder the residual envelope is used to quantize the prediction error providing step size and dynamlc bU assignment information. In stochastically excitec coders, the input to the synthesls filter is composecl by the product of the parametric envelope of the residual multiplied by an instantaneous phase taken from a codebook of random phases .

Aquest treball s'ubica dins el camp de la traductologia i el seu objectiu és fer una anàlisi lingüística de l'oralitat, centrada sobretot en el registre col·loquial, de la pel·lícula doblada al català Reservoir Dogs.

Fase previa para el desarrollo de un conversor texto a voz con soporte completo al idioma Catalán. En concreto, se trata de una adaptación del sistema "Festival", que fue desarrollado por la Universidad de Edimburgo con licencia de libre distribución. En el proyecto se definen los pasos para la creación del módulo de voz con soporte Catalán, se centrará en el estudio y aprendizaje del funcionamiento del sistema, y en los pasos para la construcción de la nueva voz, incluye una primera prueba de adaptación utilizando los módulos de soporte del idioma Español, para la creación de una voz en seudo-catalán, así como una prueba de definición de características y grabación de un nuevo corpus de voz.

One of the most popular algorithms for connected word (or subword phonetic unit) recognition is the one-stage dynamic programming algorithm. In its available formulation, this algorithm is not designed to provide multiple hypothesis; such a limitation is currently becoming a drawback, since the need of alternative recognitions in the systems presently under research is being acknowledged. This paper introduces a modified version of the one-stage dynamic programming algorithm tailored to afford multiple hypothesis.

This article presents a multimodal approach to head pose estimation of individuals in environments equipped with multiple cameras and microphones, such as SmartRooms or automatic video conferencing. Determining the individuals head orientation is the basis for many forms of more sophisticated interactions between humans and technical devices and can also be used for automatic sensor selection (camera, microphone) in communications or video surveillance systems. The use of particle filters as a unified framework for the estimation of the head orientation for both monomodal and multimodal cases is proposed. In video, we estimate head orientation from color information by exploiting spatial redundancy among cameras. Audio information is processed to estimate the direction of the voice produced by a speaker making use of the directivity characteristics of the head radiation pattern. Furthermore, two different particle filter multimodal information fusion schemes for combining the audio and video streams are analyzed in terms of accuracy and robustness. In the first one, fusion is performed at a decision level by combining each monomodal head pose estimation, while the second one uses a joint estimation system combining information at data level. Experimental results conducted over the CLEAR 2006 evaluation database are reported and the comparison of the proposed multimodal head pose estimation algorithms with the reference monomodal approaches proves the effectiveness of the proposed approach.