OneUpRender

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OneUpRender is OneUpAI's deterministic video production engine. You describe a video as a Timeline — a JSON recipe of clips, layouts, text, transitions, and audio — and the engine renders it exactly, every time. No prompts, no surprises: the same Timeline always produces the same video.

How it works

  1. Create a Project and author a Timeline (JSON). Your media enters as uploaded or generated assets — the engine never invents footage.
  2. Render a Preview to iterate quickly, then a final. Validation is strict and up-front: an invalid Timeline is rejected by name before anything is charged.
  3. The finished video lands in your asset library like any generation — durable, private, renewable URLs.

Pricing

Rendering is credit-metered per started 10 seconds of output (see the render aliases on the API docs page for the live rate). Repeated segments hit the render cache, which is why iterating on one section of a long video stays fast.

Primitive families

Every operation is a named, versioned primitive with a fixed contract. Availability is live from the capability manifest:

44 of 45 operations are available today — the rest are declared in the locked Timeline language and graduate one engineering gate at a time.

Sources & framing

Where segment pixels come from and how they fit the output frame.

  • $asset (your media) shipped
  • solid color shipped
  • fit: cover shipped
  • fit: contain shipped
  • fit: smart_crop enable-ready — waiting on needs:tracking

Layouts & split screens

Multi-frame compositions: side-by-side and stacked splits, 3-up, 2×2 and 2×3 grids, and free layouts with explicit cells — with per-cell labels (the classic BEFORE/AFTER). Picture-in-picture is an overlay.

  • compose — 2up_h · 2up_v (split screens) · 3up · grid_2x2 · grid_2x3 · free shipped
  • compose: the heard panel shipped

Motion & time

Ken Burns and push-ins, punch zooms, snap zooms, speed ramps, freeze frames, reverse, camera shake, fades.

  • zoom shipped
  • fade shipped
  • kenburns shipped
  • snap_zoom shipped
  • speed_ramp shipped
  • freeze shipped
  • reverse shipped
  • shake shipped
  • filter_preset shipped
  • rotate shipped
  • v360 shipped
  • stabilize shipped
  • parallax shipped

Transitions

Fixed, versioned join recipes between segments:

  • cut shipped
  • seamless_spin shipped
  • crossfade shipped
  • fade_black shipped
  • fade_white shipped
  • slide shipped
  • wipe shipped
  • whip shipped
  • zoom_in shipped
  • zoom_out shipped
  • circle_open shipped
  • circle_close shipped
  • pixelate shipped
  • blur_dissolve shipped

Text & captions

Word-timed captions (word-by-word, karaoke, keyword highlighting), headlines, pop-ups, callouts, lower thirds, CTAs, counters, progress bars, and stock graphics — arrows, circles, badges.

  • captions (word-timed) shipped
  • captions: one word at a time shipped
  • captions: phrase chunks shipped
  • captions: entrance / exit shipped
  • text overlays shipped
  • stock graphics shipped

Overlays

Picture-in-picture, inset video, logos and watermarks layered over segments.

  • image overlays / PiP shipped
  • video overlays / inset shipped

Audio

Music, voiceover and SFX tracks with ducking, J/L-cuts, one-shot effects (whooshes, impacts), denoise, and loudness-normalized mixing.

  • music / voiceover tracks shipped
  • ducking shipped
  • SFX one-shots shipped

New: seamless_spin

A whip-rotation transition — the camera appears to spin rapidly through space from one shot into the next, with motion blur concealing the handoff. Built for photo-to-photo sequences (listings, before/after, product sets). Direction can alternate automatically; intensity, blur, zoom and perspective are tunable.

Example: two photos joined by a spin

{
  "op": "seamless_spin",
  "duration": 1200,
  "direction": "auto",
  "intensity": 0.8,
  "motion_blur": 0.65
}

What people build with it

Before / after reveals

Split-screen comparison with labels, then a seamless spin into the close-up. The recipe is a Timeline template — swap the two photos and every render is on-brand and identical in structure.

Listing videos

A photo set becomes a walkthrough: Ken Burns motion per room, spins between rooms, captions from a script, music with auto-ducking, closing CTA card.

Captioned shorts

Cut a long recording into a vertical short: punch-ins, word-by-word captions, keyword pops, SFX hits, loudness-normalized for every platform.

Why determinism matters

Because a Timeline renders identically every time, templates are trustworthy (an agent can ship the same recipe to a thousand customers), iteration is cheap (unchanged segments come from cache), and nothing in your video is ever hallucinated — your media is the only source of pixels.