Ffmpeg Api JSON

fal-ai/ffmpeg-api/loudnorm
Get EBU R128 loudness normalization from audio files using FFmpeg API.
Inference
Commercial use

About

Apply EBU R128 loudness normalization to audio files.

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/ffmpeg-api/loudnorm", {
  input: {
    audio_url: "https://storage.googleapis.com/falserverless/example_inputs/ffmpeg-audio.wav"
  },
  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/ffmpeg-api/loudnorm", {
  input: {
    audio_url: "https://storage.googleapis.com/falserverless/example_inputs/ffmpeg-audio.wav"
  },
  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/ffmpeg-api/loudnorm", {
  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/ffmpeg-api/loudnorm", {
  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#

audio_url string* required

URL of the audio file to normalize

integrated_loudness float

Integrated loudness target in LUFS. Default value: -18

true_peak float

Maximum true peak in dBTP. Default value: -0.1

loudness_range float

Loudness range target in LU Default value: 7

offset float

Offset gain in dB applied before the true-peak limiter

linear boolean

Use linear normalization mode (single-pass). If false, uses dynamic mode (two-pass for better quality).

dual_mono boolean

Treat mono input files as dual-mono for correct EBU R128 measurement on stereo systems

print_summary boolean

Return loudness measurement summary with the normalized audio

measured_i float

Measured integrated loudness of input file in LUFS. Required for linear mode.

measured_lra float

Measured loudness range of input file in LU. Required for linear mode.

measured_tp float

Measured true peak of input file in dBTP. Required for linear mode.

measured_thresh float

Measured threshold of input file in LUFS. Required for linear mode.

{
  "audio_url": "https://storage.googleapis.com/falserverless/example_inputs/ffmpeg-audio.wav",
  "integrated_loudness": -18,
  "true_peak": -0.1,
  "loudness_range": 7
}

Output#

audio File* required

Normalized audio file

Structured loudness measurement summary (if requested)

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

Other types#

AudioTrack#

codec string* required

Audio codec used (e.g., 'aac', 'mp3')

channels integer* required

Number of audio channels

sample_rate integer* required

Audio sample rate in Hz

bitrate integer* required

Audio bitrate in bits per second

Track#

id string* required

Unique identifier for the track

type string* required

Type of track ('video' or 'audio')

keyframes list<Keyframe>* required

List of keyframes that make up this track

Audio#

media_type string

Type of media (always 'audio') Default value: "audio"

url string* required

URL where the media file can be accessed

content_type string* required

MIME type of the media file

file_name string* required

Original filename of the media

file_size integer* required

Size of the file in bytes

duration float* required

Duration of the media in seconds

bitrate integer* required

Overall bitrate of the media in bits per second

codec string* required

Codec used to encode the media

container string* required

Container format of the media file (e.g., 'mp4', 'mov')

channels integer* required

Number of audio channels

sample_rate integer* required

Audio sample rate in Hz

Keyframe#

timestamp float* required

The timestamp in milliseconds where this keyframe starts

duration float* required

The duration in milliseconds of this keyframe

url string* required

The URL where this keyframe's media file can be accessed

LoudnormSummary#

input_integrated float

Input integrated loudness in LUFS

input_true_peak float

Input true peak in dBTP

input_lra float

Input loudness range in LU

input_threshold float

Input threshold in LUFS

output_integrated float

Output integrated loudness in LUFS

output_true_peak float

Output true peak in dBTP

output_lra float

Output loudness range in LU

output_threshold float

Output threshold in LUFS

normalization_type string

Type of normalization applied (Dynamic/Linear)

target_offset float

Target offset in LU

Video#

media_type string

Type of media (always 'video') Default value: "video"

url string* required

URL where the media file can be accessed

content_type string* required

MIME type of the media file

file_name string* required

Original filename of the media

file_size integer* required

Size of the file in bytes

duration float* required

Duration of the media in seconds

bitrate integer* required

Overall bitrate of the media in bits per second

codec string* required

Codec used to encode the media

container string* required

Container format of the media file (e.g., 'mp4', 'mov')

fps integer* required

Frames per second

frame_count integer* required

Total number of frames in the video

timebase string* required

Time base used for frame timestamps

resolution Resolution* required

Video resolution information

format VideoFormat* required

Detailed video format information

audio AudioTrack

Audio track information if video has audio

start_frame_url string

URL of the extracted first frame

end_frame_url string

URL of the extracted last frame

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.

Image#

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.

width integer

The width of the image in pixels.

height integer

The height of the image in pixels.

Resolution#

aspect_ratio string* required

Display aspect ratio (e.g., '16:9')

width integer* required

Width of the video in pixels

height integer* required

Height of the video in pixels

VideoFormat#

container string* required

Container format of the video

video_codec string* required

Video codec used (e.g., 'h264')

profile string* required

Codec profile (e.g., 'main', 'high')

level float* required

Codec level (e.g., 4.1)

pixel_format string* required

Pixel format used (e.g., 'yuv420p')

bitrate integer* required

Video bitrate in bits per second