Unreal Speech JavaScript SDK

Unreal Speech JavaScript SDK allows you to easily integrate the Unreal Speech API into your JavaScript applications for text-to-speech (TTS) synthesis. This package provides convenient methods for working with the Unreal Speech API, including generating speech, managing synthesis tasks, and streaming audio.

To use the play utility, you should have FFmpeg installed on your system

FFmpeg Installation

Windows

Download FFmpeg: Go to the FFmpeg official website (https://ffmpeg.org/download.html) and download the latest build for Windows.

Mac

Install Homebrew: If not already installed, open Terminal and run /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)".

You can install the Unreal Speech JavaScript SDK via npm:

npm i unrealspeech

Available endpoints

Endpoint	Description
/stream	Stream audio for short, time-sensitive cases
/speech	Generate speech with options (MP3 format)
/synthesisTasks	Manage synthesis tasks for longer text
/synthesisTasks/TaskId	Check the status of a synthesis task

Common Request Body Schema

Property	Type	Required?	Default Value	Allowed Values
VoiceId	string	Required	N/A	Scarlett, Liv, Dan, Will, Amy
Bitrate	string	Optional	192k	16k, 32k, 48k, 64k, 128k, 192k, 256k, 320k
Speed	float	Optional	0	-1.0 to 1.0
Pitch	float	Optional	1.0	0.5 to 1.5

Parameter Details

• VoiceId:

  • Dan: Young Male
  • Will: Mature Male
  • Scarlett: Young Female
  • Liv: Young Female
  • Amy: Mature Female

• Bitrate: Defaults to 192k. Use lower values for low bandwidth or to reduce the transferred file size. Use higher values for higher fidelity.

• Speed: Defaults to 0. Examples:

  • 0.5: makes the audio 50% faster. (i.e., 60-second audio becomes 42 seconds)
  • -0.5: makes the audio 50% slower. (i.e., 60-second audio becomes 90 seconds.)

• Pitch: Defaults to 1. However, on the landing page, we default male voices to 0.92 as people tend to prefer lower/deeper male voices.

Rate Limit

Plan	Requests per second
Free	1
Basic	2
Pro	8

Obtaining an API Key

Get your API Key To use the Unreal Speech API, you'll need to obtain an API key by signing up for an account on the Unreal Speech website. Once you have an API key, you can use it to initialize the UnrealSpeechAPI class.

Usage

To use the SDK, you need to initialize it with your API key and other required configurations. Initialization

import UnrealSpeech, {play, save } from "unrealspeech";
const unrealSpeech = new UnrealSpeechAPI("your_api_key");

Methods

stream(text, voiceId, bitrate, speed, pitch, codec, temperature)

This method streams the synthesized speech based on the provided parameters.

• text: The text to be synthesized.
• voiceId: The ID of the voice to be used.
• bitrate: The bitrate of the audio.
• speed: The speed of speech.
• pitch: The pitch of speech.
• codec: The audio codec to be used.
• temperature: The temperature of speech.

Returns: A promise that resolves to the synthesized speech buffer.

createSynthesisTask(text, voiceId, bitrate, timestampType)

This method creates a synthesis task for the provided text and voice.

• text: The text to be synthesized.
• voiceId: The ID of the voice to be used.
• bitrate: The bitrate of the audio.
• timestampType: The type of timestamp to be used.

Returns: A promise that resolves to the ID of the created synthesis task.

getSynthesisTaskStatus(taskId)

This method retrieves the status of a synthesis task based on the provided task ID.

• taskId: The ID of the synthesis task.

Returns: A promise that resolves to the status of the synthesis task.

speech(text, voiceId, bitrate, timestampType)

This method synthesizes speech based on the provided text and voice.

• text: The text to be synthesized.
• voiceId: The ID of the voice to be used.
• bitrate: The bitrate of the audio.
• timestampType: The type of timestamp to be used.

Returns: A promise that resolves to the synthesized speech data.

Configuration Options

• apiKey: Your API key for authentication.
• Other configuration options and their descriptions.

Examples

stream

This method streams the synthesized speech based on the provided parameters.

import UnrealSpeech, {play, save } from "unrealspeech";
const unrealSpeech = new UnrealSpeechAPI("your_api_key");

const speechBuffer = await unrealSpeech.stream({
  text: "Hello, world!",
  voiceId: "Scarlett",
  bitrate: "192k",
  timestampType: "word",
  speed:0,
  pitch: 1.0
});

// play audio
play(speechBuffer);
// save audio
save(speechBuffer, "filename.mp3");

createSynthesisTask

const taskId = await unrealSpeech.createSynthesisTask({
 	text:  "Hello, world!",
  voiceId: "Scarlett",
  bitrate: "192k",
  timestampType: "word",
  speed: 0,
  pitch: 1.0
});

console.log(taskId); // Use the ID of the created synthesis task as needed

getSynthesisTaskStatus

const taskId = "task123"; // Replace with the actual task ID
const status = await unrealSpeech.getSynthesisTaskStatus(taskId);
console.log(status); // Use the status of the synthesis task as needed

speech

const speechData = await unrealSpeech.speech({
 	text:  "Hello, world!",
  voiceId: "Scarlett",
  bitrate: "192k",
  timestampType: "word",
  speed: 0,
  pitch: 1.0
});

console.log(speechData); // Use the synthesized speech data as needed

Code sample

You can find a code example here: code

Troubleshooting

Include common issues and their solutions.

Contributing

Contributions are welcome! If you find any issues or have suggestions for improvements, please open an issue or submit a pull request.

License

This project is licensed under the MIT License - see the LICENSE file for details.