Video
Captions and translations
How automatic AI captions work, how to correct or upload your own caption files, how AI translations into other languages are made and charged, and what students see.
Bitty Course can caption every video automatically with AI, at no extra cost on any plan. You can correct those captions or upload your own WebVTT files, and you can turn on an add-on that translates captions into other languages. Students pick a caption language in the player.
Automatic captions
When a video is ready, its speech is transcribed into captions with AI. This is on by default and included in every plan.
- Any spoken language can be transcribed. The captions are labeled with the language that was detected.
- Each version of a video is transcribed once. A new version gets its own captions. See Video versions.
To turn automatic captions on or off (owners only):
- Go to Settings → Plan & billing, section Captions.
- Check or uncheck Automatic captions.
- Click Save caption settings.
To caption videos that were live before automatic captions were on, click Caption existing videos in the same section (shown while automatic captions are on). It captions every live video that has no captions yet.
See and manage a video's captions
- Open the lesson and go to its Video tab.
- Under the version, open Captions. The number in brackets is how many caption tracks it has.
You see one row per language:
- AI-made captions carry a badge: Auto-generated (transcribed from speech) or AI translation.
- Click a language to download its
.vttfile. - Click Remove to delete that track.
- While captions are being made, you see "Generating captions from the video's speech…" or "Translating into language…".
To caption one video by hand, click Generate captions with AI. The button appears when the version has no captions and nothing is being generated. If generating fails, the reason is shown with a Try again button.
Owners and editors can generate, upload and remove captions on a video, and translate it into the languages an owner has turned on.
Correct AI captions
AI captions can mishear names, jargon and code. There's no caption editor in Bitty Course; you correct them as a file:
- Under the version's Captions, click the language to download its
.vttfile. - Fix the text in any text editor or caption tool. Keep the
WEBVTTfirst line and the timings. - Upload it under Upload your own captions with the same language code (see below).
Your file replaces the AI captions in that language, and students no longer see the AI label on it. Automatic captions never overwrite captions you uploaded.
Upload your own captions
- Open the lesson's Video tab, and open Captions under the version.
- Under Upload your own captions, fill in:
- Language code: a code like
en,esorpt-BR. - Label: what students see in the captions menu, such as "English". Up to 40 characters.
- WebVTT file (.vtt): the caption file.
- Language code: a code like
- Click Add captions.
File rules:
- Only WebVTT (
.vtt). The file must start withWEBVTT. SRT and other formats aren't accepted; convert them to WebVTT first. - Up to 512 KB per file.
- One track per language per version. To replace a track you uploaded, remove it first, then upload the new file. Uploading a language that only has AI captions replaces the AI captions directly.
Captions belong to one video version, because their timings only fit that cut. When you publish a new version, upload your captions again for it.
Translate captions into other languages (add-on)
The translations add-on uses AI to translate a video's captions into the languages you choose. It's billed by use: a price per minute of video, per language, shown in the Captions section of Settings → Plan & billing. You pay only for translations that finish, and never more than the monthly cap you set.
Languages offered: Español, Français, Deutsch, Português, Italiano, Nederlands, Polski, 日本語 (Japanese), 한국어 (Korean), 中文 (Chinese), हिन्दी (Hindi) and العربية (Arabic).
To turn it on (owners only):
- Go to Settings → Plan & billing, section Captions, box Caption translations.
- Check Translate captions of each new video into these languages.
- Under Languages, check the languages you want.
- Set the Monthly cap in dollars.
- Click Save caption settings.
How translations happen:
- After a new video is captioned, its captions are translated into each chosen language automatically.
- Translations are made from your own uploaded captions if you have them, otherwise from the automatic captions.
- A language you uploaded your own captions for is never translated over.
- To translate videos that were already live, click Translate existing videos. This counts toward your cap.
- To translate one video into the chosen languages it doesn't have yet, open its Captions and click Translate into languages.
The cap:
- Each translation reserves its charge before it starts. If it would go past this month's cap, it doesn't start, and the video shows "Not translated into language: it would go past this month's translation cap." with a Raise the cap link. After raising it, click Try again.
- A failed translation costs nothing.
- Months follow the calendar month in UTC.
- Settings → Plan & billing shows what you've spent this month against the cap. The Usage page shows it too.
Translations are machine-made and labeled AI translation. To correct one, download it, fix it, and upload it with the same language code, as described above.
What students see
- When a video has captions, students choose a caption language (or none) in the player.
- Captions you uploaded show the label you gave them.
- AI captions are always labeled as AI-made, for example "English (auto-generated)" or "Español (AI translation)". Where the player shows Bitty Course's own caption menu, students also see "These captions were made by AI and may contain mistakes." under the video.
- Students only get caption files through the same access check as the video, using short-lived links. See Playback and security.
Good to know
- Automatic captions also power Draft with AI, which drafts a lesson description, takeaways, chapters and quiz questions from the transcript.
- AI dubbing is a separate add-on that replaces the audio, not the captions.
- Captions can't be edited line by line inside Bitty Course, and there's no burned-in (open) caption option.