POST /v1/tasks. Switching models means changing model and nothing else. The three models differ in how the length is decided (a duration you send, or one the model picks), how reference material is supplied, and what they are billed on.
Available models
Omni-Flash-Ext
omni-flash-ext · fixed 4 / 6 / 8 / 10 second clips, 360p to 4K, first-frame or three-image references; billed at a whole-clip price by resolution × duration, or per second of the reference videoGemini Omni 1.1 Flash
gemini-omni-1.1-flash · model-chosen length of 3–10 s, 360p to 4K, first/last frames and up to 10 reference images; billed by resolution tier × secondsGemini Omni Flash Preview
gemini-omni-flash-preview · model-chosen length of 3–10 s, 720p only, up to 16 reference images and a reference video of up to 24 s; billed by resolution tier × secondsChoose a model
What the three models share
These are identical across all three:
The mode is not selected with
action but by what you send: prompt alone is text-to-video, image_urls makes it image-to-video, and video_urls reworks an existing clip.
Unified request
task_id. Retrieve the result with GET /v1/tasks/{task_id}, wait inline with Prefer: wait, or configure a webhook.