Auto-Caption Generation: Whisper + FFmpeg in a Node.js Worker
javascript
dev.to
Captions are no longer optional for short-form video. Studies consistently show 85%+ of social media videos are watched without sound. If your pipeline produces clips without captions, you're shipping an inferior product. This post covers the full implementation: audio extraction, Whisper transcription, timing alignment, and burning captions directly into the video with FFmpeg. This is part of the caption stack used by ClipSpeedAI. The Approach: Hardcoded vs. Soft Captions Two optio