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Auto-Captioner Video to Video

fal-ai/auto-caption
Automatically generates text captions for your videos from the audio as per text colour/font specifications
Inference
Commercial use
PlaygroundAPI

About

Caption

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/auto-caption", {
  input: {
    video_url: ""
  },
  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/auto-caption", {
  input: {
    video_url: ""
  },
  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/auto-caption", {
  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/auto-caption", {
  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#

video_url string* required

URL to the .mp4 video with audio. Only videos of size <100MB are allowed.

txt_color string

Colour of the text. Can be a RGB tuple, a color name, or an hexadecimal notation. Default value: "white"

txt_font string

Font for generated captions. Choose one in 'Arial','Standard','Garamond', 'Times New Roman','Georgia', or pass a url to a .ttf file Default value: "Standard"

font_size integer

Size of text in generated captions. Default value: 24

stroke_width integer

Width of the text strokes in pixels Default value: 1

left_align string | float

Left-to-right alignment of the text. Can be a string ('left', 'center', 'right') or a float (0.0-1.0) Default value: center

top_align string | float

Top-to-bottom alignment of the text. Can be a string ('top', 'center', 'bottom') or a float (0.0-1.0) Default value: center

refresh_interval float

Number of seconds the captions should stay on screen. A higher number will also result in more text being displayed at once. Default value: 1.5

{
  "video_url": "",
  "txt_color": "white",
  "txt_font": "Standard",
  "font_size": 24,
  "stroke_width": 1,
  "left_align": "center",
  "top_align": "center",
  "refresh_interval": 1.5
}

Output#

video_url string* required

URL to the caption .mp4 video.

{
  "video_url": ""
}

Other types#