[Free & Paid] Speech Synthesis Engine Summary: Which Software Uses Which?

Currently, many text-to-speech software programs have been released.

However, when listening to the audio from text-to-speech software, you might think, "Wait, isn't this voice the same as other software?"

In fact, text-to-speech software requires a base speech synthesis engine.

Therefore, even if the software names are different, if the speech synthesis engine is the same, the voice will be the same.

In this article, we will introduce speech synthesis engines that can be used for free and those that can be used for a fee.

We also include information that might make you think, "Oh, so that software uses this synthesis engine!"

Please take a look!

Speech synthesis engines that can be used for free

Free text-to-speech software mainly uses the following:

• AquesTalk
• Open JTalk

These speech synthesis libraries and engines are used.

AquesTalk

Developed by AQUEST Co., Ltd., AquesTalk is known for "Yukkuri Voice" and "Bouyomi Voice".

All software that can read aloud in the voice commonly referred to as "Yukkuri" uses AquesTalk.

Representative examples include Bouyomi-chan and SofTalk.

Because synthetic voices can be easily created from text, it is used in various situations ranging from personal use to commercial products.
In addition to being used as the base for SofTalk and Bouyomi-chan, it is also used for the default UTAU voice via sampling. Furthermore, it is used for guidance voices in home appliances such as telephones.

AquesTalk was first released on May 25, 2006. The development period was reportedly just under two years. (AquesTalk release)
The sound sources are created by manually manipulating parameters rather than by recording, making it a true synthetic voice with no "person inside."

In January 2010, the successor version, AquesTalk2, was announced.
It supports a wide range of platforms, including Windows, Mac OS X, WinCE, iPhone, Android, and other smartphones. Recently, an independent microchip (hardware) called AquesTalk pico has even appeared.

Source: Nico Nico Pedia

Since API usage licenses and development libraries are provided, it can be used for various purposes if you have programming skills.

Check the company's website for details.

AquestTalk

Yukkuri Voice is also explained in this article.

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Open JTalk

Open JTalk is a Japanese text-to-speech synthesis system developed at the Tokuda-Lee Laboratory of the Nagoya Institute of Technology.

It is open source, distributed under the Modified BSD License.

Open JTalk is used in Textalk. If you listen to it once, you might feel like you've heard it before.

Open JTalk

Speech synthesis engines that can be used for a fee

Famous paid speech synthesis engines include:

• IBM: Watson Text to Speech
• Google: Text to Speech
• Amazon: Polly
• Microsoft: SAPI5

There are many attractive plans, such as free usage for up to tens of thousands of characters.

Demos for the above paid speech synthesis engines are provided on their websites, where you can play and listen to the audio.

Speech synthesis engines have a high difficulty level

In this article, we introduced speech synthesis engines.

By using a speech synthesis engine, you can create your own text-to-speech software or customize it to your liking.

However, if you actually try to use them, they are provided as APIs, making configuration difficult if you cannot program.

API is an abbreviation for "Application Programming Interface," referring to "programs specialized for a single function that can be shared" or "a mechanism for sharing software functions." If frequently used functions are provided as APIs, there is no need to build a program from scratch. You can use APIs as needed to proceed with development efficiently.

In the case of Web APIs, the program is published on the web and called from outside. Web APIs are published in various fields, and many are available for free.

For example, if you can obtain the latest information from another company's site via an API, you can add new functions to your own website or app to improve the service. Since the level required for smartphone apps has increased in recent years, using Web APIs in app development has become common.

Source: internet academy

Companies that provide paid versions of text-to-speech software either develop their own speech synthesis engines or use the paid ones introduced here.

"Why not just make a speech synthesis engine in the first place?"

You might think that, but this is not an easy task.

It would be a task requiring a difficult process with many researchers, developers, and money.

At the very least, it is difficult for an individual and is not realistic unless you have the scale of a company or research institution.

Therefore, if you feel that using an API is difficult, it is more intuitive and easier to handle to use paid text-to-speech software.

Many types of text-to-speech software, from free to paid, have been released.

I am sure you will find your favorite software.

We have summarized them in detail in this article, so please check it out!

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I hope this article is helpful to you.

See you again soon.