Lucy 2.5Edit Reality as It Happens
Decart's real-time video model edits and transforms live video at the speed of the stream. Swap characters, place products, restyle whole scenes, and add special effects live, at 30fps with near-zero latency. Available now on fal.
Start building with the Lucy 2.5 API
Real-time, prompt-driven video editing over WebRTC. Restyle scenes, swap backgrounds, and place objects on live or streamed video at 30fps.
What Lucy 2.5 gives you
See products on you, live
Lucy edits live or recorded video frame by frame at 30fps, changing only what you ask while motion, lighting, and the rest of the scene stay intact. Shoppers see a product on themselves, in their room, or outdoors, in real time.
Every frame becomes live ad inventory
Lucy turns any video into live ad inventory, inserting products, transforming environments, and creating interactive moments as it plays. Pixels fixed at production become programmable, adaptable, and responsive in real time.
Characters, products, styles, and VFX
Swap or add characters, replace or remove objects, place products, change attributes, transform backgrounds, restyle scenes, and add special effects, all from a text prompt or reference image. Lucy edits the world it sees in real time, unlocking a new category of interactive gaming experiences.
See Lucy 2.5 in action
Real-time edits across products, apparel, and full scenes. Every clip below was transformed live, prompt by prompt.
Soap bottle swap
"Turn the shoe in her hand into a purple soap bottle with the W logo mark, matching her grip, the lighting, and the reflections as she moves it."
Three edits, typed in live
"Make my jacket a black button-down with gold buttons. Turn the sofa into a black leather couch. Add a window looking out on an Italian villa with an orange tree and water."
Try on looks, live
"Add a blue denim jacket on top of my current top. Then switch to a black button-down jacket with gold buttons."
Every industry that runs on video, built with Lucy 2.5
From live shopping to interactive gaming, teams use Lucy 2.5 to make live video an interactive, programmable medium.
Live shopping and virtual try-on
Let shoppers see products on themselves, in their room, or in the scene in real time during live shopping streams. Close the imagination gap and show products in context before people buy.
Real-time product placement
Insert products, swap branding, and transform environments live, turning every stream into interactive, on-brand creative with no post-production pass.
Interactive streams that convert
Change appearances, add characters, transform styles, and add special effects while the stream is live, turning passive viewing into an interactive experience.
Full scene transformation in-app
Give users real-time scene transformation inside your product, so creators can express, engage, and monetize as content is being made.
Live world editing
Lucy edits the world it sees in real time, unlocking a new category of interactive gaming experiences that respond as they run.
Virtual staging on live walkthroughs
Restage empty rooms with new furniture, decor, and finishes during a live walkthrough. Buyers see the space transformed in real time, with no physical staging or pre-rendered images.
Lucy 2.5 vs Lucy 2.1
Lucy 2.5 is the next generation: a broader editing range and higher-quality edits on the same real-time foundation. Lucy 2.1 is live on fal today when you need a real-time endpoint right now.
Lucy 2.5 API integration steps
Get ready to integrate in minutes. No GPUs to manage, no infrastructure to set up.
1. Install the client
Add the fal client for your stack, Python or JavaScript, or call the REST API directly from any language.
npm install --save @fal-ai/client
2. Create an account on fal
Sign up to get access to the dashboard and your API keys.
3. Get your API key
Grab your credentials from the developer dashboard and set them as an environment variable in your runtime.
4. Connect a stream
Connect a live or recorded video stream with your prompt over fal's realtime API and receive the transformed stream back.
Lucy 2.5 playground
Try Lucy 2.5 in the browser, then run the same real-time API from your own app.
Open the playground →Lucy 2.1 API
Prefer the previous real-time model? Lucy 2.1 by Decart is still live on fal.
View Lucy 2.1 API →
Connect to the Lucy 2.5 realtime API
Open a real-time connection over WebRTC and stream edits back as they render. Fetch a short-lived token from your backend, then send prompts on the live feed.
import { fal } from "@fal-ai/client";
const connection = fal.realtime.connect("decart/lucy-2-5/realtime", {
onResult: (result) => {
console.log(result);
},
onError: (error) => {
console.error(error);
},
// Fetch short-lived JWT token from your backend
tokenProvider: async (app) => {
const response = await fetch("/api/fal/realtime-token", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({ app }),
});
return response.text();
},
tokenExpirationSeconds: 10,
});
connection.send({});
Common questions about Lucy 2.5
What is Lucy 2.5?
Lucy 2.5 is Decart's latest real-time video and world editing model. It turns video into a programmable medium, transforming people, products, environments, and visual effects live as content is created, streamed, or consumed.
Is Lucy 2.5 available on fal?
Yes. Lucy 2.5 is live on fal now. Try it in the playground or integrate the real-time API directly. Lucy 2.1 by Decart is also available if you need the prior real-time model.
What can I do with Lucy 2.5?
Swap or add characters, replace, add, or remove objects, place products, change attributes, transform backgrounds, apply new visual styles, and generate special effects, all in real time on live or recorded video.
Why does real-time matter?
Real-time turns video from a fixed asset into a dynamic experience. Instead of deciding every pixel before publishing, creators and brands adapt content live, making video interactive, responsive, and programmable.
How does Lucy 2.5 preserve scene continuity?
Lucy 2.5 changes only the requested element while preserving the rest. Motion, lighting, background, and scene structure stay stable across frames, so edits look natural in live streams and recorded video alike.
Does the video quality degrade over long streams?
No. Lucy is trained to correct itself over long sessions, so streams run for hours without identity collapse or visual degradation.
How is Lucy 2.5 different from Lucy 2.1?
Lucy 2.5 broadens the editing range and raises quality across characters, products, styles, and VFX, building on the real-time foundation of Lucy 2.1. The Lucy 2.1 API is available on fal today if you need a real-time endpoint right now.
How much does it cost?
Lucy 2.5 is $0.04 per second of video on fal. It's serverless and usage-based, so you only pay for what you process, with no minimums and no infrastructure to manage.
How do I get access?
Lucy 2.5 is live on fal now. Try it in the playground or integrate the real-time API directly. It's serverless, so there are no GPUs to manage and no infrastructure to set up.
Can I use Lucy 2.5 for commercial projects?
Yes. Output generated through the fal API can be used in commercial projects. Check fal.ai's terms of service for full details on usage rights and licensing.
Get in touch about Lucy 2.5
Lucy 2.5 is live on fal. Want to talk through your use case or partner with us? Leave your details and our team will reach out.