Gemini Omni edit 400: aspect_ratio is not supported, framing is kept

Sending aspect_ratio with a video_url edit on gemini-omni-flash-1.1 returns a 400 on Sume. Why the output keeps the source framing and what to send.

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If your edit call to gemini-omni-flash-1.1 returns 400 with a message that aspect_ratio is not supported on edit (video_url), remove the field. The output keeps the source framing, so there is nothing to choose. Sume's Video Router docs list the edit mode as video_url plus a prompt, with resolution optional (default 720p) and no aspect_ratio or duration.

The request that fails and the one that works

A text-to-video call on this model accepts 16:9 or 9:16. The same field on an edit is rejected, because the source clip already fixes the shape.

curl -X POST https://api.sume.com/v1/video-router/generate \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-omni-flash-1.1",
    "prompt": "Replace the bottle with an apple. Keep everything else the same.",
    "video_url": "https://example.com/clip.mp4",
    "resolution": "720p",
    "mode": "async"
  }'

Edit-mode field rules

Google's Omni page limits input videos for editing to 10 seconds (read 2026-10-03), so trim long sources first. To match another shape, crop or re-render afterward rather than asking the edit to reframe.

Fields on a gemini-omni-flash-1.1 edit (read 2026-10-03)
FieldOn edit
video_urlRequired; the source clip
resolutionOptional, default 720p
aspect_ratioRejected with 400
durationNot a length setting; the output follows the source
image_url, end_image_url, reference_*_urlsCannot be combined with video_url

Sources

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