Relight
The client provides a convenient way to interact with the model API.
npm install --save @fal-ai/clientThe @fal-ai/serverless-client package has been deprecated in favor of @fal-ai/client. Install the new package and update your imports — see client setup.
Set FAL_KEY as an environment variable in your runtime.
export FAL_KEY="YOUR_API_KEY"The client API handles the API submit protocol. It will handle the request status updates and return the result when the request is completed.
import { fal } from "@fal-ai/client";
const result = await fal.subscribe("fal-ai/id-v2v/relight", {
input: {
prompt: "An astronaut walking through an autumn forest",
video_url: "https://storage.googleapis.com/falserverless/model_tests/video_models/mmaudio_input.mp4",
image_url: "https://storage.googleapis.com/falserverless/example_inputs/ltxv-image-input.jpg"
},
logs: true,
onQueueUpdate: (update) => {
if (update.status === "IN_PROGRESS") {
update.logs.map((log) => log.message).forEach(console.log);
}
},
});
console.log(result.data);
console.log(result.requestId);The API uses an API Key for authentication. It is recommended you set the FAL_KEY environment variable in your runtime when possible.
import { fal } from "@fal-ai/client";
fal.config({
credentials: "YOUR_FAL_KEY"
});When running code on the client-side (e.g. in a browser, mobile app or GUI applications), make sure to not expose your FAL_KEY. Instead, use a server-side proxy to make requests to the API. For more information, check out our server-side integration guide.
The client API provides a convenient way to submit requests to the model.
import { fal } from "@fal-ai/client";
const { request_id } = await fal.queue.submit("fal-ai/id-v2v/relight", {
input: {
prompt: "An astronaut walking through an autumn forest",
video_url: "https://storage.googleapis.com/falserverless/model_tests/video_models/mmaudio_input.mp4",
image_url: "https://storage.googleapis.com/falserverless/example_inputs/ltxv-image-input.jpg"
},
webhookUrl: "https://optional.webhook.url/for/results",
});You can fetch the status of a request to check if it is completed or still in progress.
import { fal } from "@fal-ai/client";
const status = await fal.queue.status("fal-ai/id-v2v/relight", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b",
logs: true,
});Once the request is completed, you can fetch the result. See the Output Schema for the expected result format.
import { fal } from "@fal-ai/client";
const result = await fal.queue.result("fal-ai/id-v2v/relight", {
requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b"
});
console.log(result.data);
console.log(result.requestId);Some attributes in the API accept file URLs as input. Whenever that's the case you can pass your own URL or a Base64 data URI.
You can pass a Base64 data URI as a file input. The API will handle the file decoding for you. Keep in mind that for large files, this alternative although convenient can impact the request performance.
You can also pass your own URLs as long as they are publicly accessible. Be aware that some hosts might block cross-site requests, rate-limit, or consider the request as a bot.
We provide a convenient file storage that allows you to upload files and use them in your requests. You can upload files using the client API and use the returned URL in your requests.
import { fal } from "@fal-ai/client";
const file = new File(["Hello, World!"], "hello.txt", { type: "text/plain" });
const url = await fal.storage.upload(file);The client will auto-upload the file for you if you pass a binary object (e.g. File, Data).
Read more about file handling in our file upload guide.
prompt string* requiredThe prompt describing the restyled video to generate.
video_url string* requiredURL of the source video whose motion and framing drive the generation.
image_url string* requiredURL of the restyled first frame. The video is regenerated in this frame's identity/style.
Optional restyled keyframes pinned at specific output frame indices to anchor identity over long videos.
resolution ResolutionEnumOutput resolution tier. Orientation follows the source video (720p is 1280x720 or 720x1280; 480p is 832x480 or 480x832). Default value: "720p"
Possible enum values: 480p, 720p
num_frames integerMaximum number of output frames. Capped at the source video's frame count. Default value: 81
num_inference_steps integerNumber of diffusion sampling steps per clip. Higher improves quality but is slower. Default value: 30
guidance_scale floatClassifier-free guidance scale. Controls prompt adherence versus creativity. Default value: 5
vace_scale floatVACE conditioning scale. Controls how strongly the source video's structure constrains the generation. Default value: 1
seed integerRandom seed for reproducibility. The same seed is used for every clip of a multi-clip generation.
enable_safety_checker booleanEnable safety checking of inputs and outputs. Default value: true
{
"prompt": "An astronaut walking through an autumn forest",
"video_url": "https://storage.googleapis.com/falserverless/model_tests/video_models/mmaudio_input.mp4",
"image_url": "https://storage.googleapis.com/falserverless/example_inputs/ltxv-image-input.jpg",
"keyframes": [
{
"image_url": "https://storage.googleapis.com/falserverless/example_inputs/ltxv-image-input.jpg",
"frame_index": 80
}
],
"resolution": "720p",
"num_frames": 81,
"num_inference_steps": 30,
"guidance_scale": 5,
"vace_scale": 1,
"enable_safety_checker": true
}The generated video file.
seed integer* requiredThe seed used for generation.
{
"video": {
"content_type": "video/mp4",
"file_name": "output.mp4",
"url": "https://storage.googleapis.com/falserverless/example_outputs/scail2-output.mp4",
"file_size": 1048576
}
}url string* requiredThe URL where the file can be downloaded from.
content_type stringThe mime type of the file.
file_name stringThe name of the file. It will be auto-generated if not provided.
file_size integerThe size of the file in bytes.
image_url string* requiredURL of a restyled keyframe image. It is pinned verbatim at frame_index to anchor identity over long videos. Its aspect ratio must match the output aspect ratio within 0.1.
frame_index integer* required0-based output frame index for this keyframe. Must be >= 1 (frame 0 is the restyled first frame from image_url) and less than the output frame count.