Automatic Video Subtitling

Site noise the microphone struggles with

A site safety training video picks up plant noise, a mix of accents from whoever is speaking, and in-house acronyms, permit references, equipment codes, that no general-purpose dictionary recognises. The training officer who has to roll it out to new starters rarely has the time or the skill to subtitle it by hand, so the video often stays as it is, unusable for operators who work with ear defenders on.

Subtitles that drift out of sync undermine the video

We regularly see consumer subtitling tools perform well on a studio recording with a lapel mic and no background noise, then struggle on real footage from the field: they transcribe the technical acronym as the nearest everyday word, lose sync the moment one sentence overlaps another, and produce a translation that flattens the register of the trade. The pilot impresses on the clip chosen to demonstrate it, then disappoints on the first real footage handed to it afterwards.

A glossary first, the algorithm second

We only take this on if a business glossary already exists, even as an internal spreadsheet, or if someone agrees to build one before the first batch of videos goes through, without it, the model trips over the same acronyms on every shoot. We also ask for the languages actually needed to be chosen explicitly, rather than a long list that multiplies review work with no audience behind it. For a one-off video, or footage with poor audio, we generally advise against automating this.

Sign-off stays human on sensitive content

We transcribe the audio, time the subtitles to match speech rhythm, and apply the glossary agreed in advance. For regulatory or safety videos, the trainer or the relevant department reviews the result before release: they confirm the technical term has been rendered correctly and that nothing has been mistranscribed on a point that touches operator safety.