Against the background of the ongoing pandemic, this year’s Computational
Paralinguistics Challenge featured a classification problem to detect
Covid-19 from speech recordings. The presented approach is based on
a phonetic analysis of speech samples, thus it enabled us not only
to discriminate between Covid and non-Covid samples, but also to better
understand how the condition influenced an individual’s speech
signal.
Our deep acoustic model was trained with datasets collected exclusively
from healthy speakers. It served as a tool for segmentation and feature
extraction on the samples from the challenge dataset. Distinct patterns
were found in the embeddings of phonetic classes that have their place
of articulation deep inside the vocal tract. We observed profound differences
in classification results for development and test splits, similar
to the baseline method.
We concluded that, based
on our phonetic findings, it was safe to assume that our classifier
was able to reliably detect a pathological condition located in the
respiratory tract. However, we found no evidence to claim that the
system was able to discriminate between Covid-19 and other respiratory
diseases.