US Patent 8027836 Phonetic decoding and concatentive speech synthesis

A speech processing system includes a multiplexer that receives speech data input as part of a conversation turn in a conversation session between two or more users where one user is a speaker and each of the other users is a listener in each conversation turn. A speech recognizing engine converts the speech data to an input string of acoustic data while a speech modifier forms an output string based on the input string by changing an item of acoustic data according to a rule. The system also includes a phoneme speech engine for converting the first output string of acoustic data including modified and unmodified data to speech data for output via the multiplexer to listeners during the conversation turn.