Ephemeral upload: a temporary route for an input
An ephemeral upload is a temporary place to put an input file so a request can point at it. On pages that offer one it usually carries a much higher size ceiling than sending the same file inline or by ordinary link. As of 2026-09-12.
| Route | Typical position | What it is for |
|---|---|---|
| Inline in the request | The tightest ceiling | Small images, quick tests |
| By ordinary link | A middle ceiling | Assets already hosted somewhere |
| An ephemeral upload | The loosest ceiling | Large references and conditioning clips |
Inclusion rule. Routes a generation page can document for supplying an input, ordered by how much they typically allow. Order. Tightest route first.
1The route is part of the specification
Where the same file is accepted one way and refused another, the choice of route is not an implementation detail. It decides whether a high resolution reference can be used at all, and the spread between routes can be very large.
That belongs in the pipeline design rather than in a footnote, because a job that worked in testing with a small reference can fail in production with a real one.
2It is temporary by design
The word ephemeral is doing work: the upload is not storage and it is not an archive. Anything a campaign will reuse has to live somewhere the buyer controls, and the upload is a hand-off rather than a home.
That mirrors what happens on the output side, where a result often arrives as a link with an expiry. In both directions the vendor is holding the file only long enough to do the job.
3It says nothing about the output
Every figure in this family governs what goes in. None of them describes the size of the file that comes back, which is the figure a delivery check against a surface's upload cap actually needs.
That gap is the normal state of the file column: requirements on the surface side, input ceilings on the generator side, and no overlap between the two.
A vocabulary entry: the definition, plus how the specification pages on these sheets usually publish it. Table checked 2026-09-12. Nearby entries: Model identifier, Increment.
4A generator's ad pipeline
For ad work around “Ephemeral upload”, SceneMixer's pages explain how its ad projects are produced:
Seedance 2.0 (ByteDance's video model family) is one of the strongest engines for vertical short drama in 2026.
SceneMixer, Seedance 2.0 in a Real Short-Drama Pipeline (read 2026-10-13)
Video is 16:9 landscape by default, with 9:16 vertical available; you set it once per project. Segments are typically 4 to 15 seconds, and some model tiers go to 30.
SceneMixer, AI Short Drama Generator — “What length and aspect ratio does it output?” (read 2026-10-13)