An Open Source Speech Synthesis Frontend for HTS

Abstract. This paper describes a software framework for HMM-based speech synthesis that we have developed and released to the public. The framework is compatible to the well-known HTS toolkit by incorporating hts engine and Flite. It enables HTS voices to be used as Microsoft Windows system voices and to be integrated into Android and iOS apps. Non-English languages are supported through the capability to load Festival format pronunciation dictionaries and let-ter to sound rules. The release also includes an Austrian German voice model of a male, professional speaker recorded in studio quality as well as pronuncia-tion dictionary, letter to sound rules and basic text preprocessing procedures for Austrian German. The framework is available under an MIT-style license