US Patent 10176819 Phonetic posteriorgrams for many-to-one voice conversion

A method for converting speech using phonetic posteriorgrams (PPGs). A target speech is obtained and a PPG is generated based on acoustic features of the target speech. Generating the PPG may include using a speaker-independent automatic speech recognition (SI-ASR) system for equalizing different speakers. The PPG includes a set of values corresponding to a range of times and a range of phonetic classes, the phonetic classes corresponding to senones. A mapping between the PPG and one or more segments of the target speech is generated. A source speech is obtained, and the source speech is converted into a converted speech based on the PPG and the mapping.