  Speech translation (ST) automatically converts utterances in a source
language into text in another language. Splitting continuous speech into
shorter segments, known as speech segmentation, plays an important role in ST.
Recent segmentation methods trained to mimic the segmentation of ST corpora
have surpassed traditional approaches. Tsiamas et al. proposed a segmentation
frame classifier (SFC) based on a pre-trained speech encoder called wav2vec
2.0. Their method, named SHAS, retains 95-98% of the BLEU score for ST corpus
segmentation. However, the segments generated by SHAS are very different from
ST corpus segmentation and tend to be longer with multiple combined utterances.
This is due to SHAS's reliance on length heuristics, i.e., it splits speech
into segments of easily translatable length without fully considering the
potential for ST improvement by splitting them into even shorter segments.
Longer segments often degrade translation quality and ST's time efficiency. In
this study, we extended SHAS to improve ST translation accuracy and efficiency
by splitting speech into shorter segments that correspond to sentences. We
introduced a simple segmentation algorithm using the moving average of SFC
predictions without relying on length heuristics and explored wav2vec 2.0
fine-tuning for improved speech segmentation prediction. Our experimental
results reveal that our speech segmentation method significantly improved the
quality and the time efficiency of speech translation compared to SHAS.
