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<Paper uid="P84-1113">
  <Title>VOICE SIMULATION: FACTORS AFFECTING QUALITY AND NATURALNESS</Title>
  <Section position="2" start_page="0" end_page="0" type="intro">
    <SectionTitle>
ABSTRACT
</SectionTitle>
    <Paragraph position="0"> In this paper we describe a flexible analysls-synthesls system which can be used for a number of studies In speech research. The maln objective Is to have a synthesis system whose characteristics can be controlled through a set of parameters to realize any desired voice characteristics. The basic synthesis scheme consists of two steps: Generation of an excitation signal from pitch and galn contours and excitation of the linear system model described by linear prediction coefficients, We show that a number of basic studies such as time expansion/ compression, pitch modifications and spectral expansion/compression can be made to study the effect of these parameters on the quality of synthetic speech. A systematic study is made to determine factors responsible for unnaturalness tn synthetic speech. It is found that the shape of the glottal pulse determines the quality to a large extent. We have also made some studies to determine factors responsible for loss of Intelligibility tn some segments of speech. A signal dependent analysts-synthesis scheme ts proposed to improve the intelligibility of dynamic sounds such as stops. A simple implementation of the signal dependent analysis is proposed.</Paragraph>
  </Section>
class="xml-element"></Paper>