Investigating the Differences Between European Portuguese Sounds: An Approach Using Polygonal Mesh Comparison

Abstract

With the main purpose of studying the articulatory configuration of the European Portuguese (EP) sounds and to evaluate coarticulatory effects, a large 3D MRI database from several speakers and contexts have been acquired. Segmentation, visualization and interpretation of all the available data, essential to a detailed characterization of these sounds, are complex and time-consuming tasks. To perform the segmentation, a semi-automatic method was used. Meshes of the tongue were created from the segmented volumes and a polygonal mesh comparison tool (PolyMeCo) was used to compare: different sounds, the same sound produced in different contexts and syllabic positions, and productions from different speakers, providing a qualitative measure of these differences. To the best of our knowledge this is the first study in the literature using such an approach to analyze and compare tongue shape. Furthermore, these first results are very promising allowing a proper analysis and depiction of the main differences between EP sounds and further insight into their production.