Quick answer
Video translation is a chain: recognise the speech, translate the text, fit it to the timeline, then voice it. The weakest link sets the quality of the whole thing, and it is usually the first one.
Why audio quality decides the outcome
- Everything downstream translates whatever the recogniser produced, correct or not
- Background noise, overlapping speakers, and strong accents cause errors the translation stage cannot detect
- Technical terms and proper nouns are the most common recognition failures, and the most damaging
- A clean source recording improves the final result more than any later adjustment
What happens between recognition and the finished file
- The transcript is translated with the surrounding context in view, rather than line by line
- The translation is fitted to the timeline, since languages differ in how long the same meaning takes to say
- Subtitles are constrained to a readable length and duration per line
- Where voice output is used, it is aligned to the original timing
Where to intervene for the biggest gain
- Start from the best audio you have, not the compressed export
- Correct the transcript before translating, since fixing a name once is cheaper than fixing it in every subtitle
- Review terminology first — that is where automated output most often needs help
- Export subtitles as SRT, adjust them, and re-import rather than redoing the whole job
What Belin Doc provides
Automatic subtitle generation across languages, SRT import and export for manual correction, voice output with language switching, and subtitle embedding into the finished video. See the video translator and the dedicated subtitle translator.
Bottom line
Fix the audio and the transcript first. Work spent there improves everything downstream; work spent polishing the final output does not travel back up the chain.