Transducer Misalignment in Ultrasound Tongue Imaging
Tamás Gábor Csapó, Kele Xu, Andrea Deme, Tekla Etelka Gráczi, Alexandra Markó · Repository of the Academy's Library (Library of the Hungarian Academy of Sciences) · 2021
A long-standing problem for ultrasound tongue imaging is the transducer misalignment during longer data recording sessions. In this paper, we present an initial idea for analyzing such misalignment. The method employs Mean Square Error (MSE) distance to identify the relative displacement between the chin and the transducer. We visualize these measures as a function of the timestamp of the utterances. Experiments are conducted on various ultrasound tongue datasets (UltraSuite, and recordings of Hungarian children and adults). The results suggest that extreme values of MSE indicate corruptions or issues during the data recordings, which can either be caused by transducer misalignment, lack of gel, or missing contact between the skin and the transducer. The methods are language independent and might be applied in phonetic analysis of ultrasound recordings.