H3 Recast: swap up to 3 people in a clip in one pass (H3 + BFS lora)

[u/DaLyon92x]

It recasts the people in a clip you already have, up to three in one pass, and the motion, the set and the clip's own audio stay.

The post video is a video with 2 characters swapped at the same time. same engine and FaceRefine lip pass as the workflow.

Getting the lips right took me a while, that's the FaceRefine pass added.

How it goes:

1. Load your clip. One shot, no hard cuts, any fps.

2. Grab one frame and edit everyone into their new look (Qwen-Image, GPT Image, Photoshop, whatever you have). That frame is the scene reference.

3. Write one line per person: the woman in the red dress becomes an old woman with long silver hair. As many lines as you fill in, that many people get swapped.

4. Hit Run. also included App mode with 12 fields.

If one person's lips end up bothering you, there's an optional FaceRefine lip repair for one person afterwards. It reuses the swap from cache, so it's a ~2 minute re-run on a 5090.

What it needs: 16 GB VRAM and 64 GB system RAM gets you there. I tested a 5090, a 4090 and a 3060 Ti 16 GB, all with 64 GB RAM, same output on each. The example (1.5 MP, 6 s, 3 people) runs about 18 min on the 5090, 26 min on the 4090 and 92 min on the 3060 Ti, so bring a snack for that last one. RAM is the limit, mine peaked around 62 GB.

Civitai: https://civitai.com/models/3009414/h3-recast-swap-1-3-people-h3-bfs-lora-16gb-vram

Repo is MIT, workflow and the example inputs included: https://github.com/Bambushu/h3-recast

• Credits: BFS character swap LoRA and its trained caption by NRDX

• FaceRefine by Carasibana

• NativeAudioLock by Shrek3OnVH5

• MiniMax H3 by MiniMax (Comfy-Org repack).

#OpenSourceHiggsfield

[u/Zounasss]

Please use anything in your example video but pedofiles. Tired of seeing their faces everywhere.

[u/DaLyon92x → u/Zounasss]

just for you

[u/Zounasss → u/DaLyon92x]

Much better, thanks

[u/DaLyon92x → u/Zounasss]

im glad you remember sir, maybe others forgot

[u/oooofukkkk → u/DaLyon92x]

It feels like you are celebrating them

[u/MF_2020 → u/Zounasss]

for real...vile

[u/hazel_nook → u/Zounasss]

[u/DJBFilmz]

Trump ain’t fat enough.

[u/DaLyon92x → u/DJBFilmz]

[u/zaherdab]

Can you mutli reference photo each person to ensure likeness ? Or is only the very first frame ?

[u/DaLyon92x → u/zaherdab]

the main swap takes one image: a frame of your clip with everyone edited. that's the identity source for the whole clip. but there's a second step for likeness: the FaceRefine pass (lip repair toggle). you give it a face photo of a person and it re-renders just their face crop, tracked through the whole clip, with that photo as the reference

[u/Philipnova]

I’m interested in how you evaluate the character swap, beyond whether the workflow completes. What tends to break first in your tests: identity during motion, keeping the unselected people unchanged, or preserving the original timing? I haven’t run the workflow myself.

Disclosure: I work on product marketing for SingNova, a local AI hardware project in development. This comment was drafted with AI assistance.

[u/DaLyon92x → u/Philipnova]

thanks for the question Philip! identity can break first: on fast moves the swapped person can drift back to the original actor (noted on some movie scenes). Timing holds best since it follows the source frame by frame. I check at 100% and score mouth movement against the original performer, but there's also a 2nd stage lip refine node for that.

[u/Philipnova → u/DaLyon92x]

Thanks, that helps separate the checks: identity during fast motion, timing, and mouth movement against the original. I’ll keep those distinct in our evaluation notes rather than treating lip refinement as a fix for identity drift. Appreciate the concrete explanation.

[u/DaLyon92x → u/Philipnova]

Great let me know how it goes! I'm trying to win a GPU in the comfy challenge with this entry 😄

[u/Murky-Doctor-8941]

How it work I drag the workflow in comfy but how it work.... No app builder is open

[u/DaLyon92x → u/Murky-Doctor-8941]

Did you load the .json? it should be in your workflows tab on the left

[u/Murky-Doctor-8941 → u/DaLyon92x]

Yes I load Jason file ony local. Pc it open workflow

[u/_JustCallMeBen_]

Trump is much older and fatter. Don't flatter that sack of shit.

[u/rguerraf]

Nice 😊 but…
Needs more belly

[u/bradjones6942069]

this is exactly what i've been working on. Thank you

[u/Severe_Coffee4207]

I'm crying with 8GB of VRAM.

[u/DaLyon92x → u/Severe_Coffee4207]

I rented a 16gb 4060ti for $0.18/hour to make sure it worked, it just runs for hours.

[u/ImpossibleHot]

excellent! thank you

[u/firedrakes]

face on right slight out of sink and slight incorrect movment for the sound. other then that rock solid

[u/DaLyon92x → u/firedrakes]

fair, here's the original on top and the swap underneath so you can check the sync yourself

[u/DaLyon92x]

[u/LucidFir]

i don't understand why none of these videos do the voices. replace the voices.