Replace one prop in a video with AI: bottle to apple edit prompt

To replace one object in an existing video, send the clip as video_url to gemini-omni-flash-1.1 and prompt the swap in one sentence plus a keep clause. The Sume Video Router docs use this exact request as the model's edit example: "Replace the bottle with an apple. Keep everything else the same." at 720p. The output follows the source clip, so a prop swap leaves the camera, the timing and the people as they were, and you pay for an edit job and not for a new generation.

This page walks through that example field by field, because each field in the edit shape either does something or is refused, and the refusals are what trip people up.

The request, field by field

The edit request is the smallest request on the video surface. Only four fields matter, and each of the other video fields is either ignored for edit or rejected.

{
  "model": "gemini-omni-flash-1.1",
  "prompt": "Replace the bottle with an apple. Keep everything else the same.",
  "video_url": "https://example.com/source.mp4",
  "resolution": "720p",
  "duration": 8
}

What the swap can and cannot depend on

The prompt is the only input that describes the new object. A reference photo is not allowed with video_url, so "an apple" has to be specific enough in words: say "a red apple" or "a green apple with a stem", not just "fruit". If the new object has to be an exact product, a new generation with reference images is the right route, and an edit is not.

The old object also needs to be unambiguous. If three bottles are on the table, name the one you mean by position or color: "the bottle on the left". A clear target matters more than a long prompt.

Why the duration field is only a hint

The provider does not return an output length for edits, so Sume cannot know the final length when the job is admitted. It reserves from the duration you send, and falls back to 8 seconds when you send nothing. The Video Router doc marks the exact meaning of this as something that still needs verification against the provider, so treat the reserve as an upper estimate and not as a promise of the settled price.

The practical rule is to send the true length of your source clip. A 6 second clip reserved as 8 seconds reserves about a third more than the clip needs. Sending a duration above your clip's real length does not make the output longer.

What it costs at an 8 second hint

Sume bills the provider list times 1.25 on each row, rounded up to the cent for a job. The table shows the 8 second default hint, which is what a request reserves when it sends no duration. At the default 720p resolution an 8 second edit reserves $1.00. For the arithmetic on other lengths, see Omni edit billing and the 8 second reserve.

When to re-roll and when to edit

A prop swap is also the easiest edit to judge. You know where the object was, so you can scrub to the frames where a hand touches it and see at once whether the new object holds its shape. Check those frames before the rest.

Use an edit when the scene is right and one object is wrong. Use a new take when the camera move or the action is wrong, because an edit cannot fix those, and a clip with the wrong action is a candidate for a new take at a lower resolution first. The deciding question is whether the thing you want to change is the same thing the source clip has already settled. For the three routes side by side, read fixing one detail in a finished clip.