create-ai-avatar
Create AI Avatar
HeyGen API · ElevenLabs · ffmpeg. Scripts are plain Node 20 and bash, with no packages to install.
An avatar of you is three things, each from its best source. The face and the way you move come from your own footage (a HeyGen digital twin). The voice is your own clone on ElevenLabs, made into an audio file. One engine lip-syncs the two. You then judge the result where likeness breaks first: the mouth, close up, beside your real one.
Boundary. Use html-explainer-video for a film with no face in it, and html-reel to cut your real phone takes into a reel. Use this skill when the person on screen should be you, saying words you didn't record.
Provenance. Built in November 2026 on a creator's own twin, trained from the eye-contact takes of one YouTube video (2 min 48 s) and voiced in his ElevenLabs clone on v4. The same 8.8-second line was rendered on all three engines, and the creator picked by the mouth. The demo shows four presenters made from single portraits as HeyGen photo avatars, so nobody's real footage is on show.
The mechanism
Keep the face, the voice and the lip-sync apart, and only ever change one of them. The twin is trained once. The voice is a file you listen to before it goes anywhere. A render is the twin plus that file on one engine. When something looks wrong you can then tell which part to change. Use the same line and the same audio for every engine you compare: a new line hides what the engine did.
HeyGen can't use an ElevenLabs voice by its id. Make the line on ElevenLabs (scripts/voice.mjs), then send HeyGen the audio as audio_asset_id or audio_url instead of script and voice_id. The video is as long as the audio, up to 30 minutes.
Judge it by the mouth. In a whole frame every engine looks fine. Crop the nose-to-chin box at six moments of each render and of your real footage, and stack them (scripts/mouths.sh). Then look at how wide the lips stretch, how much of the teeth show, the colour of the lips and the corners of the mouth.