Open source speech synthesis: Everything you need to know

What is open source speech synthesis, and how does it work? Here is everything you need to know about this technology.

Speech synthesis, a fascinating branch of artificial intelligence, has seen tremendous advancements in the recent years. An integral part of this progress can be attributed to the open source community, which has introduced a variety of powerful tools that are transforming the way we understand and use speech synthesis.

Let’s delve into the realm of open source speech synthesis, exploring its workings, and highlighting some top tools in this field.

What does open source mean?

Open source software is designed to allow anyone access to the software's source code. This approach encourages collaboration, as it enables developers to study, adjust, and distribute the software according to their needs. The continual improvement from a community of developers accelerates the software's evolution, enhancing its reliability and adaptability.

Within the speech synthesis field, open source refers to publicly accessible tools and libraries that offer functionalities like text to speech (TTS), speech recognition, and transcription. These tools' source code is often hosted on platforms like GitHub, encouraging global collaboration to improve and customize these systems. Thus, open source is a significant driving force in advancing speech synthesis technology.

What is speech synthesis technology?

Speech synthesis, also known as text to speech synthesis, is a technology that converts written text into spoken words. It's commonly used in various apps on Windows, Android, and MacOS systems to assist visually impaired users, automate voice responses in telecommunication systems, or provide real-time narration in multimedia applications.

The underlying mechanism involves complex machine learning algorithms trained on vast datasets of recorded human speech. These algorithms analyze the input text, decipher its linguistic and phonetic details, and generate a corresponding audio waveform. This waveform is then transformed into a human-like voice, often capable of producing speech in different languages like English or Russian.

Benefits of speech synthesis

Speech synthesis technology offers numerous benefits. It has transformative applications in many sectors, including accessibility, communication, entertainment, and education. By converting text into speech, it provides a voice for those who cannot speak and aids the visually impaired by reading out digital text. In communication, it powers virtual assistants, making human-machine interactions more natural and efficient. It also has entertainment applications, narrating e-books, generating dialogue in video games, and dubbing films. In education, it aids in language learning and can read out lessons for auditory learners. Moreover, its ability to generate speech in different accents and languages promotes inclusivity and global communication. Overall, speech synthesis technology significantly enhances user experiences and accessibility in digital platforms.

How does open source speech synthesis work?

Open source speech synthesis tools employ similar methodologies as proprietary systems but with the added advantage of transparency and customization. Developers can access, modify, and optimize these tools according to their specific use case.

Typically, these tools come with a command line interface and APIs, allowing users to integrate them into their workflows. Python and Java are common languages used in their development. The system takes the input text, pre-processes it into a format understandable by the machine learning model (often a transformer-based model), then generates the speech waveform. This waveform can be saved as an audio file, like a WAV file, or used in real-time applications.

Most tools also include extensive docs and tutorials, aiding users in understanding the tool's dependencies and helping them set up the environment, whether it be Linux, Windows, or MacOS. In some systems, the processing can be offloaded to a GPU for faster results, especially important in real-time speech synthesis.

Top open source speech synthesis tools

Open source speech synthesis has democratized the way we approach text to speech synthesis, providing accessible and customizable tools for developers worldwide. By understanding these tools, their functioning, and the various use cases they serve, we can gain insights into how to effectively integrate and leverage them in various applications.

Here are some noteworthy open source speech synthesis tools, each with unique features and advantages:

eSpeak

An incredibly compact open source speech synthesizer compatible with Windows, Linux, and MacOS. eSpeak supports several languages, including English and Russian, and it can be employed through command line or a simple API.

Flite (Festival Lite)

Developed by the Carnegie Mellon University (CMU), Flite is a lightweight and versatile speech synthesis engine. It's designed to work on embedded systems and large servers alike.

MaryTTS

MaryTTS is a Java-based open source text to speech system, featuring high-quality voices and an extensive toolkit for generating new voices. It provides support for multiple languages and a customizable HTML interface.

Coqui TTS

A powerful TTS tool developed by Coqui, it leverages advanced transformer models for high-quality speech synthesis. Coqui TTS's user-friendly Python interface, extensive documentation, and community support make it a preferred choice for developers.

Mycroft's Mimic

Mycroft offers Mimic, an open source text to speech engine, as a part of its open source voice assistant. Mimic allows developers to create custom voices and can be used as a standalone TTS tool.

Mozilla's TTS

Built with Python, Mozilla's TTS offers a unique combination of traditional signal processing techniques with advanced machine learning models, providing high-quality speech output. It supports GPU acceleration, making it a suitable choice for real-time applications.

Get high-quality speech synthesis with Speechify Voiceover Studio

While open source speech synthesis is a helpful tool and fun to experiment with, it doesn’t offer consistent and high-quality results or not enough customization options. Speechify Voiceover Studio steps in to take speech synthesis to the next level. This platform features more than 120 natural-sounding voices in over 20 different languages and accents—and all of the generated speech can be customized in great detail for pitch, pronunciation, pauses, and many more speech elements. Users also enjoy 100 hours of voice generation per year, fast audio editing and processing, unlimited uploads and downloads, thousands of licensed soundtracks, commercial usage rights, and 24/7 customer support.

Experience the best of speech synthesis with Speechify Voiceover Studio.