Timeline fit modes: cover, contain, stretch, blur for ad clips
Sume Timeline video[].fit has four modes: cover (default), contain, stretch and blur. What each does to a clip that does not match the output frame.
When a source clip does not match your output frame, set video[].fit in a Sume Timeline render: cover (the default), contain, stretch or blur. Pick contain or blur when you must not crop a product, and avoid stretch unless distortion is acceptable. Source: Timeline.
The four modes
Test your own clip to see how each mode looks before a batch.
| `fit` | Intended behaviour | Risk |
|---|---|---|
| cover | Fill the frame | May crop edges |
| contain | Fit inside the frame | Leaves empty bars |
| stretch | Fill by scaling both axes | Distorts proportions |
| blur | Fit inside, with a blurred background | Background is not the product |
Other video[] rules
video[].duration is the on-screen length, at least 0.2 s, and coverage may trail the audio spine by at most 0.5 s.
Cost reminder
Render is $0.10 per started output minute; compose is a separate $0.02 flat (list prices from Sume's catalog rate card (GET /v1/catalog), confirmed in the repo's catalog file read 2026-10-03).
Sources
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Written by Sume