The MBROLA Project Alternatives

The MBROLA Project

The aim of the MBROLA project, initiated by the TCTS Lab of the Faculté Polytechnique de Mons (Belgium), is to obtain a set of speech synthesizers for as many languages as possible, and provide them free for non-commercial applications. The ultimate goal is to boost academic research on speech synthesis, and particularly on prosody generation, known as one of the biggest challenges taken up by Text-To-Speech synthesizers for the years to come.

Central to the MBROLA project is MBROLA, a speech synthesizer based on the concatenation of diphones. It takes a list of phonemes as input, together with prosodic information (duration of phonemes and a piecewise linear description of pitch), and produces speech samples on 16 bits (linear), at the sampling frequency of the diphone database used (it is therefore NOT a Text-To-Speech (TTS)synthesizer, since it does not accept raw text as input). This synthesizer is provided for free, for non commercial, non military applications only.

Diphone databases tailored to the Mbrola format are needed to run the synthesizer. A French voices have been made available by the authors of MBROLA, and the MBROLA project has itself been organized so as to incite other research labs or companies to share their diphone databases. The terms of this sharing policy can be summarized as follows :

After some official agreement between the author of MBROLA and the owner of a diphone database, the database is processed by the author and adapted to the Mbrola format, for free. The resulting Mbrola diphone database is made available for non-commercial, non-military use as part of the MBROLA project. Commercial rights on the Mbrola database remain with the database provider for exclusive use with the Mbrola software.