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How to burn captions/subtitles onto a video

Short answer: Ask the AI to caption your video. It transcribes the audio locally with Whisper, writes a subtitle file from the timing, then permanently draws the text onto the picture, all on your machine, nothing uploaded.

Steps

  1. Get your video into the workspace (drag it into the Files panel, or use the import-file toolbar button). You can just ask in chat (the AI enables media editing itself when needed), but Studio mode has it on by default.
  2. Ask the AI to caption the clip: “burn captions onto this video.” It transcribes the spoken audio locally into timestamped segments; a long file takes a few minutes.
  3. Check the transcript the AI shows you (or ask for corrections); the captions are only as good as the transcript. The speech model is English-only, and music, singing, or heavy background noise transcribe poorly.
  4. The AI writes a subtitle file from the transcript’s timings.
  5. It burns the captions onto the video, producing a new file with the text baked into the picture: the same kind of hardcoded captions you see on Shorts, Reels, and TikTok. This step re-encodes the video; the audio track is untouched.
  6. Preview the finished clip in the chat’s media gallery.

Notes & gotchas

  • Burned-in captions can’t be toggled off: they’re part of the picture. If you just want the subtitle file itself (to load into an editor, or toggle separately), say so and skip the burn-in step.
  • Font coverage: plain Latin text renders reliably; non-Latin scripts (CJK, Arabic) or emoji may show as boxes depending on installed fonts.
  • Nothing leaves your machine: transcription and caption burning both run locally through the bundled speech model and FFmpeg.
  • Want the clip reframed to vertical too? See how to clip a video into a vertical Short locally: reframe first, then caption, or the other way around, either works.