Demo — inputs & output
Prompt structure inspired by Inspired by fal.ai H3 Guide
Cat-to-Dog Replacement
Single-subject replacement edit — swap cat for dog in existing footage.
Who this is for
Quick localized edit demos and meme-style revisions.
How this prompt is built
Read this first — once you see the pattern, you can write your own without starting from zero.
- Edit instruction
One substitution + stability constraint.
Adapt it for your project
- Specify breed or size.
- Add behavior note (sitting, walking).
Where people mess up
- Regenerating entire scene instead of local edit.
- Scale mismatch on floor contact.
Full prompt (copy & edit)
Replace the cat in the video with a dog. Keep everything else in the shot stable: background, camera motion, lighting, and timing. Match the dog's scale and contact shadows to the original subject.
New to Ref2VA? Read the MiniMax H3 Ref2VA prompt guide
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