FLUX video edit API: 720p downscale, and video_url edits on Sume

BFL's "Edit a video" endpoint sets duration, resolution, aspect ratio and audio from your source clip and downscales sources larger than 720p to 720p. Sume has no FLUX video model; its video-to-video edit is the video_url field with gemini-omni-flash-1.1, the only model that accepts it.

BFL's text is from its docs index (the page is undated); Sume's from the Video Router docs, read 2026-09-30.

What does the BFL endpoint do?

The index describes it as transforming a source clip with an edit instruction. The server sets duration, resolution, aspect ratio and audio from the source, and sources above 720p are downscaled to 720p. It does not accept FLUX 3 generation controls such as mode, version, seed or generate_audio.

How does editing work on Sume?

What does that mean for source clips?

Gemini Omni Flash 1.1 is documented at 3 to 10 seconds for generation. The docs state no source-length limit and no 720p downscale rule, so test a short clip first. The clip is the edit source, not a reference: to condition a fresh generation on a clip instead, the schema points to reference_video_urls.

What does an edit request look like?

POST to /v1/video-router/generate with an Idempotency-Key, model: "gemini-omni-flash-1.1", your prompt, video_url and mode: "async". Prompt wording tips are in Gemini Omni video edit prompts.