WORLD is free software for high-quality speech analysis, manipulation and synthesis. It can estimate Fundamental frequency (F0), aperiodicity and spectral envelope and also generate the speech like input speech with only estimated parameters.
This source code is released under the modified-BSD license. There is no patent in all algorithms in WORLD.
I introduce useful software in WORLD. If you want to introduce your project in WORLD, please contact me.
PyWorldVocoder (https://github.com/JeremyCCHsu/Python-Wrapper-for-World-Vocoder) is a Python wrapper for World Vocoder.
Note: To avoid making the project complicated, I decided not to merge it to my repository and introduce your project here. The other reason is that I can't support some computer languages.