How to Replace the Person in a Video With Your Own AI Character (Character Swap on Wan 3.0)

To replace the person in a video with your own AI character, open Character Swap in ReelMint, pick the video, let the studio find the people in it, choose "swap the whole character" and cast your character into the person you want replaced. The video is re-filmed on Wan 3.0 in pieces of up to 14 seconds, with your character doing the same moves on the same background, and the original sound is put back at the end.

We build ReelMint. This post covers the whole-character mode step by step: what the input has to be, how to choose a reference that works, what it costs, and the cases where it struggles. If you only want to change faces, that is the other mode, covered in the Character Swap guide.

What "swap the whole character" changes

Character Swap has two modes at the same price:

• Swap the faces: only each cast person's face and hair change. Clothes, body, scene and motion stay.
• Swap the whole character: each cast person becomes the chosen character completely: face, hair, build and clothes. They do exactly the same moves, to the same music, on the same background, with the same camera.

This post is about the second. It is the one you want when your character has its own outfit and body type, for example a cartoon mascot taking over a dance clip, or your brand character walking through a real street video.

Step 1: pick the video

Go to Studio, then Character Swap, and choose a video from your library. The limits:

• up to 120 seconds and 50 MB;
• at least 3 seconds long.

Upload the clip to your library first if it came from your phone. A clip with one clear person who stays in frame is the easiest case.

Step 2: find the people (2 credits)

Press Find the people. The studio samples frames across the video and one vision pass lists everyone it found, ranked by how much of the video they are in, with a crop of each. Up to eight people are listed, marked main or side. This pass costs 2 credits.

Step 3: choose the mode and cast your character

Choose Swap the whole character. Then, for the person you want replaced, choose one of your characters or any photo in your library. You can cast up to four people in one swap; anyone you leave out stays exactly as they are.

The reference decides the result. For a whole-character swap, use a look that shows the character head to toe in the outfit you want. A head-and-shoulders portrait gives the model a face but has to invent the rest. In the Character Studio, a look comes with a turnaround sheet (front, sides, back), which gives the model the most to copy. How to create reusable characters covers making one.

Step 4: pick the resolution and read the price

Choose 480p, 720p (the default) or 1080p. The button shows the total in credits before you start, and that total is what is charged.

How the price is built: each piece is a Wan 3.0 reference job priced on the seconds of the source piece plus the seconds it films, so the total grows with the length of the video. 480p costs half of 720p per second, and 1080p costs twice 720p. When there is more than one piece, the editor's join is added. Casting four people costs the same as casting one.

Step 5: swap and wait

Press Swap. Behind the button:

1. The video is cut into pieces of up to 14 seconds (a remainder under 3 seconds is merged into the piece before it).
2. Each piece is re-filmed once from the original piece and your character's reference, with every cast person in the same run. Two pieces are filmed at a time, and a failed piece is retried once.
3. The pieces are joined and the original sound is laid back under the new picture.

The result lands in your library as a new post. You can download it, cut it in the editor, or post it to your channels from the Share button.

Why 14-second pieces

Wan 3.0 takes a reference clip of up to 15 seconds. A cut asked for exactly 15 seconds can come out a frame long, so we cut at 14 to stay inside the limit every time. A 46-second clip, for example, becomes pieces of 14, 14, 14 and 4 seconds.

Honest caveats

• Joins can show. Each piece is filmed separately, so on a long clip a detail can shift slightly from one piece to the next. Shorter videos and strong references reduce it.
• Fast, crowded scenes are harder. People who cross, overlap or leave frame make it harder to keep the right person replaced.
• Real people are not a good reference. Models may refuse a recognisable real face. Use a character you made.
• The content screen still runs, as it does on every generation.
• Longer clips take longer. Expect minutes per piece, not seconds.

If you want to restyle the whole video instead of replacing a person, that is video to video; see how to restyle a video with a prompt. Plans start at Lite, $9.99 a month for 800 credits, and every plan runs every model.

Can AI replace a person in a video with a different character?

Yes. In ReelMint's Character Swap, choose "swap the whole character" and the cast person becomes your character completely, face, hair, build and clothes, doing the same moves with the original sound.

How long can the video be?

Up to 120 seconds and 50 MB, and at least 3 seconds. It is filmed in pieces of up to 14 seconds and joined.

Which model does Character Swap use?

Wan 3.0 in its reference mode, for both the face mode and the whole-character mode.

Does the music stay?

Yes. The pieces are filmed silent and the original sound is put back under the finished video.

Does swapping more people cost more?

No. Up to four people are swapped in the same run for the same price as one.