Adding live captions and multilingual VOD subtitles to online classes
For international students, learners who need hearing support, and classes heavy with technical terms, captions make a real difference. They are needed at two moments: live captions while the class runs, and VOD subtitles on the recording that students replay later. This guide covers both and shows how NetServ Education handles each.
1. Live captions during class
Education turns class audio into captions and translates them into the language each student picks. There are two modes.
| Aspect | Default (free) mode | Server captions |
|---|---|---|
| Where it runs | Each browser's own speech recognition and translation | The instructor's microphone audio is processed by the server through external recognition and translation AI (Deepgram, Claude) |
| Terminology | Depends on the browser | Technical terms are pulled from the syllabus, announcements and material titles (lecture PDFs can register terms too) and fed into recognition |
| Correction | None | Claude corrects Korean misrecognitions in context before translating |
| Plan | Included in Free | Paid (higher quality), runs only when the instructor turns it on |
The caption window can be dragged anywhere, and server captions stop when the instructor leaves the class. Because server captions send audio to external AI, choose them knowingly.
2. Multilingual subtitles for recorded lectures (VOD)
Audio from a recorded lecture is recognized on the server (whisper) to create subtitles, then translated into other languages (translation uses Claude and is a higher-plan feature). A progress bar, a cancel button and an estimated time make long jobs easy to follow. Students choose a subtitle language when they replay, and instructors can watch per language or download the subtitle file (.vtt) for use elsewhere.
3. Interface languages for international students
The student view and classroom menus switch between Korean, English, Chinese and Vietnamese. Combined with captions, this lowers the language barrier in one step, and students join from a browser without installing anything.
4. A suggested rollout
First, try browser captions on the Free plan to confirm the flow. Second, for courses heavy with terminology, turn on server captions and compare accuracy. Third, for courses students review often, generate VOD subtitles so students can pick their language. Server live captions and multilingual VOD subtitles are higher-plan (Premium) features; school or institution accounts and a dedicated server (by agreement) can be discussed under self-hosting. Educational use has free-to-discounted tracks, so check the Pricing page.
Frequently asked questions
Do students have to install anything?
No. Students join with a browser such as Chrome or Edge and an invite link, including phone browsers. The desktop app is for instructors who want to drive PowerPoint directly.
Are live captions and VOD subtitles the same feature?
No. Live captions show speech instantly during class; VOD subtitles are generated afterwards by recognizing and translating the recording on the server. Students pick the subtitle language on replay.
Can I reuse the subtitle files elsewhere?
Yes. Instructors can download per-language subtitle files (.vtt).