Alan W Black and Paul Taylor (C) Centre for Speech Technology Research University of Edinburgh 80 South Bridge Edinburgh EH1 1HN

Festival offers a general framework for building speech synthesis systems as well as including examples of various modules. As a whole it offers full text to speech through a number APIs: from shell level, though a Scheme command interpreter, as a C++ library, and an Emacs interface.

Festival is multi-lingual, we have develeoped voices in many languages including English (UK and US), Spanish and Welsh, though English is the most advanced. The system is written in C++ and uses the Edinburgh Speech Tools for low level architecture and has a Scheme (SIOD) based command interpreter for control. Documentation is given in the FSF texinfo format which can generate a printed manual, info files and HTML.

HTK is a toolkit for use in research into automatic speech recognition and has been developed by the Speech Vision Robotics Group at the Cambridge University Engineering Department.

HTK was originally developed at the Cambridge University Engineering Department (CUED). In 1993 Entropic Research Laboratory Inc. acquired the rights to sell HTK and the development of HTK was fully transferred to Entropic in 1995 when the Entropic Cambridge Research Laboratory Ltd was established.

HTK was sold by Entropic until 1999 when Microsoft bought Entropic. Microsoft has now licensed HTK back to CUED and is providing support so that CUED can redistribute HTK and provide development support via the HTK3 web site. While Microsoft retains the copyright to the existing HTK code, everybody is encouraged to make changes to the source code and contribute them for inclusion in HTK3.