CaptionshaperWhisper
OpenAI's speech model, run locally with whisper.cpp
Hi, I'm Elvis.
I'm Elvis Zygmanta. Hollowbit is my studio for small, free tools that do one job well and treat the people using them with respect.
Why Captionshaper exists
Captions are no longer optional. Most people watch short videos with the sound off, and a video without captions gets scrolled past.
The usual tools upload your video to a server, put the best styles behind a subscription and add a watermark until you pay. For something a normal computer can do in a minute, that felt wrong.
Captionshaper does it on your own computer, for free: accurate captions, styles that look like the ones you see every day, and nothing uploaded.
What Hollowbit sticks to
- No ads
- Not in the app, not on the website.
- No accounts
- You shouldn't need to sign up to caption a video.
- No tracking
- No analytics and no data collection.
- Open source
- Every line of code is public.
How it's built
Silero VAD
Finds where people speak
Word-level timing
Token timestamps matched to the voice
libass and FFmpeg
Burns the captions into the video
Electron
One app for Mac and Windows
Tested
Automated tests drive the real app and measure accuracy