Typical workflow
Review the scene plan before submitting all segments together.
Upload a standard MP4 and wait for segment previews.
Add a portrait to every generated segment. Keep complex group scenes or footage you do not want to change.
Submit the plan to process and merge with source audio. Inspect results, redo a segment if needed, and download the full video.
Direct answers about formats, quality, consent, and this site's current product limits.
Prepare a clear solo MP4 and a portrait. Start with a short clip to check the result.