Segmentation and Analysis of Vocal Tract from MidSagittal Real-Time MRI

The articulatory description of European Portuguese (EP) requires the analysis of different anatomical structures (e.g. tongue dorsum and velum), and the study of dynamic aspects of speech production. The use of real-time magnetic resonance imaging (RT-MRI), with frame rates above 10 frames/s, provides adequate support for these studies and results in a large amount of images that need to be processed to extract relevant data to be analysed by linguists. To tackle the required data processing and analysis this article presents methods to perform segmentation of the vocal tract from midsagittal real-time MR image sequences and provide researchers with visualizations of the relevant extracted data. Examples are provided illustrating the analysis of dynamic aspects of EP nasal vowels.