Omni 40-second ad: resend the packshot at every 10-second step

Resend the product image with every 10-second step. Google says Gemini Omni 1.1 Flash extends a clip to at most 40 seconds, in 10-second increments, and that the model can analyze up to 10 seconds of prior context. A product that appears at second 3 is therefore 30 seconds of footage away from the model's view by second 33, so give each step the packshot again.

Sume does not list an extend mode. You get the same shape with four separate 10-second gemini-omni-flash-1.1 clips, each with the packshot in reference_image_urls, joined on a Timeline. Four clips at 720p cost $5.00, plus $0.10 for the render.

What Google documents

The Google announcement gives the 40-second cumulative limit, the 10-second increments and the 10-second context window. The model page lists 3 to 10 seconds per output at 360p, 720p, 1080p and 4K, at 24 FPS, and up to 10 seconds of input for editing and extension.

Neither page says how well an object holds its look across steps. Treat drift as a risk to test, not a measured rate.

The Sume equivalent

On Sume, reference_to_video takes up to 10 reference images and up to 3 reference videos of at most 3 seconds each. You refer to them in the prompt as <IMAGE_REF_0>. Native audio is always on and generate_audio: false is rejected, so each clip brings its own sound.

Because each clip is its own job, the packshot is a fixed input that the job reads each time. That is the point of the workaround: the model never has to remember the product from 30 seconds earlier.

What you give up

Four independent clips are not one continuous take. There is no carried-over motion between steps, so plan cut points at natural beats and use short Timeline transitions. A native extension keeps motion flowing; the Sume route trades that for a fixed product look and four prices you can retry one at a time.

A retry of one bad 10-second step costs $1.25 at 720p. The rates above are the Sume card on 2026-10-07; read pricing_skus from GET /v1/videos/models before you budget.