Minimax H3 Recast

It performs a cast substitution rather than generating video from nothing: the portraits you supply take the place of the performers in your existing clip, while movement, framing, edits and audio are all carried over from the original.

Keep the clip between 5 and 30 seconds, with no single shot running past 15 seconds. Split longer takes before uploading, because the output comes back the same length as the input.

Up to four, each with its own portrait. By default the tool maps them to the leads in screen order, so arrange your uploads accordingly; a written prompt can change that mapping.

One sharp, evenly lit, forward-facing portrait per person works best. Half-body framing carries hair and clothing more faithfully than a tight crop; avoid sunglasses, hats, hidden faces, group photos, heavy filters and blurry images.

Start with the low-resolution pass to check the pairing, then render the deliverable at 1080p. Because cost scales with clip length, that first pass is the cheap way to catch a mismatch.

It cannot change the footage itself — different movement, different camera work or a different location all have to come from your source. Results also weaken with dense crowds, tiny or distant faces, fast motion, and objects blocking a face after a hard cut; over long takes or when someone turns to profile, the likeness may drift back toward the original performer.