Extend a video with new footage based on a prompt, faster.
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("minimax/h3-max-turbo/extend-video", {
input: {
video_url: "https://storage.googleapis.com/falserverless/example_inputs/flux-3-red-panda.mp4",
prompt: "The red panda keeps walking along the log, then looks up at a bird."
},
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("minimax/h3-max-turbo/extend-video", {
input: {
video_url: "https://storage.googleapis.com/falserverless/example_inputs/flux-3-red-panda.mp4",
prompt: "The red panda keeps walking along the log, then looks up at a bird."
},
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("minimax/h3-max-turbo/extend-video", {
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("minimax/h3-max-turbo/extend-video", {
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.
video_url string* requiredURL of the video to extend. Must be 1.625 s to 60 s long, up to 50 MB, aspect ratio between 0.4 and 2.5.
prompt string* requiredWhat happens next. Describe the continuation, not the source.
Optional audio references for the continuation (2–15 seconds each, 15 seconds combined). The full extended video retains its original source soundtrack, and its ending still conditions the transition. These clips guide the newly generated audio instead of using that soundtrack as an audio reference. Assign each clip a role in the prompt, such as 'Audio 1 for the voice' and 'Audio 2 for background music'.
enable_prompt_expansion booleanAutomatically enhance the prompt using the source video to help keep the continuation consistent. May increase processing time. Default value: true
duration floatSeconds of new footage to add. The continuation clip also includes 1.625 seconds from the source's ending and may be longer because of frame rounding. Default value: 5
resolution ResolutionEnumOutput video resolution. Default value: "768P"
Possible enum values: 480P, 768P, 1080P, 2K
aspect_ratio AspectRatioEnumOutput aspect ratio. 'auto' follows the source video. Other values crop the video to fit the selected ratio. Default value: "auto"
Possible enum values: auto, 21:9, 16:9, 4:3, 1:1, 3:4, 9:16
seed integerSeed for the continuation. Random when omitted.
output OutputEnum'extended' returns the source and new footage as one video. 'continuation' returns a clip that starts with a 1.625-second repeat of the source's ending, then shows the new footage. Default value: "extended"
Possible enum values: extended, continuation
enable_safety_checker booleanModerate the source video and the prompt. Default value: true
{
"video_url": "https://storage.googleapis.com/falserverless/example_inputs/flux-3-red-panda.mp4",
"prompt": "The red panda keeps walking along the log, then looks up at a bird.",
"enable_prompt_expansion": true,
"duration": 5,
"resolution": "768P",
"aspect_ratio": "auto",
"output": "extended",
"enable_safety_checker": true
}The returned video. In 'continuation' mode, it includes the 1.625-second repeat at the start.
seed integer* requiredSeed used for the continuation.
duration float* requiredSeconds of returned video.
Source video information: width, height, frame rate, duration, and audio.
expanded_prompt stringThe prompt used after expansion, or null when unchanged.
{
"video": {
"url": "",
"content_type": "image/png",
"file_name": "z9RV14K95DvU.png",
"file_size": 4404019
}
}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.