Recent years have seen an increased interest in the computational speech
processing of Maltese, but resources remain sparse. In this paper, we consider
data augmentation techniques for improving speech recognition for low-resource
languages, focusing on Maltese as a test case. We consider three different
types of data augmentation: unsupervised training, multilingual training and
the use of synthesized speech as training data. The goal is to determine which
of these techniques, or combination of them, is the most effective to improve
speech recognition for languages where the starting point is a small corpus of
approximately 7 hours of transcribed speech. Our results show that combining
the data augmentation techniques studied here lead us to an absolute WER
improvement of 15% without the use of a language model.Comment: 12 page