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Video As Prompt Video to Video

fal-ai/video-as-prompt
A model for unified semantic control in video generation. It animates a static reference image using the motion and semantics from a reference video as a prompt.
Inference
Commercial use
Schema
LLMs
PlaygroundAPI

About

Generate video using Wan2.1-14B model

1. Calling the API#

Install the client#

The client provides a convenient way to interact with the model API.

npm install --save @fal-ai/client

Setup your API Key#

Set FAL_KEY as an environment variable in your runtime.

export FAL_KEY="YOUR_API_KEY"

Submit a request#

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/video-as-prompt", {
  input: {
    prompt: "A chestnut-colored horse stands on a grassy hill against a backdrop of distant, snow-dusted mountains. The horse begins to inflate, its defined, muscular body swelling and rounding into a smooth, balloon-like form while retaining its rich, brown hide color. Without changing its orientation, the now-buoyant horse lifts silently from the ground. It begins a steady vertical ascent, rising straight up and eventually floating out of the top of the frame. The camera remains completely static throughout the entire sequence, holding a fixed shot on the landscape as the horse transforms and departs, ensuring the verdant hill and mountain range in the background stay perfectly still.",
    video_url: "https://storage.googleapis.com/falserverless/bytedance-vid2pro/object-725.mp4",
    image_url: "https://storage.googleapis.com/falserverless/bytedance-vid2pro/animal-2.jpg",
    video_description: "A hand holds up a single beige sneaker decorated with gold calligraphy and floral illustrations, with small green plants tucked inside. The sneaker immediately begins to inflate like a balloon, its shape distorting as the decorative details stretch and warp across the expanding surface. It rapidly transforms into a perfectly smooth, matte beige sphere, inheriting the primary color from the original shoe. Once the transformation is complete, the new balloon-like object quickly ascends, moving straight up and exiting the top of the frame. The camera remains completely static and the plain white background is unchanged throughout the entire sequence."
  },
  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);

2. Authentication#

The API uses an API Key for authentication. It is recommended you set the FAL_KEY environment variable in your runtime when possible.

API Key#

In case your app is running in an environment where you cannot set environment variables, you can set the API Key manually as a client configuration.
import { fal } from "@fal-ai/client";

fal.config({
  credentials: "YOUR_FAL_KEY"
});

3. Queue#

Submit a request#

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/video-as-prompt", {
  input: {
    prompt: "A chestnut-colored horse stands on a grassy hill against a backdrop of distant, snow-dusted mountains. The horse begins to inflate, its defined, muscular body swelling and rounding into a smooth, balloon-like form while retaining its rich, brown hide color. Without changing its orientation, the now-buoyant horse lifts silently from the ground. It begins a steady vertical ascent, rising straight up and eventually floating out of the top of the frame. The camera remains completely static throughout the entire sequence, holding a fixed shot on the landscape as the horse transforms and departs, ensuring the verdant hill and mountain range in the background stay perfectly still.",
    video_url: "https://storage.googleapis.com/falserverless/bytedance-vid2pro/object-725.mp4",
    image_url: "https://storage.googleapis.com/falserverless/bytedance-vid2pro/animal-2.jpg",
    video_description: "A hand holds up a single beige sneaker decorated with gold calligraphy and floral illustrations, with small green plants tucked inside. The sneaker immediately begins to inflate like a balloon, its shape distorting as the decorative details stretch and warp across the expanding surface. It rapidly transforms into a perfectly smooth, matte beige sphere, inheriting the primary color from the original shoe. Once the transformation is complete, the new balloon-like object quickly ascends, moving straight up and exiting the top of the frame. The camera remains completely static and the plain white background is unchanged throughout the entire sequence."
  },
  webhookUrl: "https://optional.webhook.url/for/results",
});

Fetch request status#

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/video-as-prompt", {
  requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b",
  logs: true,
});

Get the result#

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/video-as-prompt", {
  requestId: "764cabcf-b745-4b3e-ae38-1200304cf45b"
});
console.log(result.data);
console.log(result.requestId);

4. Files#

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.

Data URI (base64)#

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.

Hosted files (URL)#

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.

Uploading files#

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);

Read more about file handling in our file upload guide.

5. Schema#

Input#

prompt string* required

The prompt to generate an image from.

video_url string* required

reference video to generate effect video from.

image_url string* required

Input image to generate the effect video for.

seed integer

Random seed for reproducible generation. If set none, a random seed will be used.

num_frames integer

The number of frames to generate. Default value: 49

fps integer

Frames per second for the output video. Only applicable if output_type is 'video'. Default value: 16

video_description string* required

A brief description of the input video content.

enable_safety_checker boolean

If set to true, the safety checker will be enabled. Default value: true

aspect_ratio AspectRatioEnum

Aspect ratio of the generated video. Default value: "9:16"

Possible enum values: 16:9, 9:16

resolution ResolutionEnum

Resolution of the generated video. Default value: "480p"

Possible enum values: 480p, 580p, 720p

guidance_scale float

Guidance scale for generation. Default value: 5

{
  "prompt": "A chestnut-colored horse stands on a grassy hill against a backdrop of distant, snow-dusted mountains. The horse begins to inflate, its defined, muscular body swelling and rounding into a smooth, balloon-like form while retaining its rich, brown hide color. Without changing its orientation, the now-buoyant horse lifts silently from the ground. It begins a steady vertical ascent, rising straight up and eventually floating out of the top of the frame. The camera remains completely static throughout the entire sequence, holding a fixed shot on the landscape as the horse transforms and departs, ensuring the verdant hill and mountain range in the background stay perfectly still.",
  "video_url": "https://storage.googleapis.com/falserverless/bytedance-vid2pro/object-725.mp4",
  "image_url": "https://storage.googleapis.com/falserverless/bytedance-vid2pro/animal-2.jpg",
  "num_frames": 49,
  "fps": 16,
  "video_description": "A hand holds up a single beige sneaker decorated with gold calligraphy and floral illustrations, with small green plants tucked inside. The sneaker immediately begins to inflate like a balloon, its shape distorting as the decorative details stretch and warp across the expanding surface. It rapidly transforms into a perfectly smooth, matte beige sphere, inheriting the primary color from the original shoe. Once the transformation is complete, the new balloon-like object quickly ascends, moving straight up and exiting the top of the frame. The camera remains completely static and the plain white background is unchanged throughout the entire sequence.",
  "enable_safety_checker": true,
  "aspect_ratio": "9:16",
  "resolution": "480p",
  "guidance_scale": 5
}

Output#

video File* required

The URLs of the generated video.

{
  "video": {
    "url": "",
    "content_type": "image/png",
    "file_name": "z9RV14K95DvU.png",
    "file_size": 4404019
  }
}

Other types#

File#

url string* required

The URL where the file can be downloaded from.

content_type string

The mime type of the file.

file_name string

The name of the file. It will be auto-generated if not provided.

file_size integer

The size of the file in bytes.