Minimum clip length by Sume video model: 2, 3, 4 or 5 seconds

On Sume the shortest accepted clip is 2 seconds on wan-3.0, 3 seconds on gemini-omni-flash-1.1, 4 seconds on the Seedance family and on higgsfield-genjutsu, and 5 seconds on minimax-h3, minimax-h3-max and h3-max-recast. A Sora-era request for a 2 or 3 second loop cannot go to most backends unchanged. This table is the lookup for the duration field when you port.

The table

Minimums and maximums are from the Sume docs and its pricing code. The docs add that every catalog model not named separately has a 15-second maximum.

Why the minimum bites

Short loops, stings and thumbnails-in-motion are the clips most likely to fall below a model's floor. A 3-second brand sting works on Omni and Wan. It is rejected on the Seedance and H3 families because it is shorter than 4 or 5 seconds. The cheap workaround is to ask for the minimum and trim: Sume's video trim cuts a range from a hosted clip at $0.02 per job.

Genjutsu and Recast are different in kind. Their duration is the source video's length, rounded up, not a creative choice, and the output follows the source's framing. Recast also rejects a source with a shot over 15 seconds.

A rule for a fallback list

If your code names a primary model and a fallback, the duration you can send safely is the overlap of their ranges. For Omni and Seedance 2.0 that is 4 to 10 seconds. Add Wan and the lower bound stays 4. Add H3 and it rises to 5. The overlap post works out the combinations.

What the minimum costs

The minimum is also the cheapest test render. At 480p, a 2-second Wan clip is the smallest Wan job; the Wan list is $0.05 per second at 480p, so Sume's price is about $0.0625 a second, or $0.125 for the minimum clip. Check GET /v1/videos/models for the live numbers before using that for a budget.

Reading the limits in code

Do not hard-code this table. The docs say to use the Video Models API before you submit, since limits differ by model and new models appear. A short function that reads supported_durations, takes the first and last values, and returns the window is enough. The list is whole seconds, so an array from 4 to 15 has twelve entries.

Also remember that the Auto route is narrower than any single model. sume/auto creates 3 to 10 second clips at 16:9 or 9:16 with defaults of 720p and 8 seconds, according to the Video Router docs, so a request that is valid for wan-3.0 at 20 seconds is not valid for Auto.

Why the minimum matters in a port

Sora clients often generate short beats. A 2-second insert is valid on wan-3.0 only; on gemini-omni-flash-1.1 it must become 3 seconds, on the Seedance models 4, and on MiniMax H3 or H3 Max 5. If your fallback chain moves a clip from the first to the last of those, it grows by three seconds and costs more, so decide in advance whether you round up, trim afterward, or fail the job.