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Workflow Utilities Audio to Audio

fal-ai/workflow-utilities/impulse-response
FFMPEG Utility for Impulse Response
Inference
Commercial use

About

Apply impulse response (IR) convolution reverb to audio.

Uses FFmpeg's afir filter to convolve the input audio with an impulse response file, creating realistic reverb and spatial effects. Supports wet/dry mix control and loudness normalization.

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/workflow-utilities/impulse-response", {
  input: {
    audio_url: "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.wav",
    impulse_response_url: "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.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/workflow-utilities/impulse-response", {
  input: {
    audio_url: "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.wav",
    impulse_response_url: "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.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/workflow-utilities/impulse-response", {
  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/workflow-utilities/impulse-response", {
  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 main audio file to process

impulse_response_url string* required

URL of the impulse response WAV file (reverb/effect profile)

dry_level float

Level of the original (dry) signal in the mix (0.0-1.0) Default value: 0.7

wet_level float

Level of the processed (wet) signal in the mix (0.0-1.0) Default value: 0.3

loudness_i float

Target integrated loudness in LUFS (typically -24 to -14) Default value: -18

loudness_lra float

Loudness Range target in LU (typically 5-15) Default value: 8

loudness_tp float

Maximum true peak in dBTP (typically -2 to -1) Default value: -1.5

output_bitrate OutputBitrateEnum

Output audio bitrate Default value: "192k"

Possible enum values: 128k, 192k, 256k, 320k

{
  "audio_url": "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.wav",
  "impulse_response_url": "https://v3.fal.media/files/panda/1-0iezBUIePBa3Sz5YY5B_tmpy1jyshw9.wav",
  "dry_level": 0.7,
  "wet_level": 0.3,
  "loudness_i": -18,
  "loudness_lra": 8,
  "loudness_tp": -1.5,
  "output_bitrate": "192k"
}

Output#

audio AudioFile* required

The processed audio file with reverb applied

{
  "audio": {
    "file_size": 2456789,
    "file_name": "impulse_output.wav",
    "content_type": "application/octet-stream",
    "url": "https://v3b.fal.media/files/b/panda/impulse_output.wav"
  }
}

Other types#

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.

file_data string

File data

width integer

The width of the image in pixels.

height integer

The height of the image in pixels.

AudioFile#

url string* required

URL of the audio file

content_type string* required

Content type of the audio file

file_name string* required

Name of the audio file

file_size integer* required

Size of the audio file in bytes

SubtitleSegment#

start float* required

Start time in seconds (e.g., 0.0 for beginning, 5.5 for 5.5 seconds)

end float* required

End time in seconds (must be greater than start time)

text string* required

Subtitle text to display (supports multiple lines with )

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.

file_data string

File data

EQBand#

frequency float* required

Center frequency in Hz (20-20000)

width float

Bandwidth in Hz Default value: 100

gain float* required

Gain in dB (-30 to 30, negative = cut, positive = boost)