Web-based educational tools for speech technology 

Kåre Sjölander, Joakim Gustafson, Jonas Beskow, Björn Granström, and Rolf Carlson
Centre for Speech Technology (CTT) 
    Department of Speech, Music and Hearing (TMH) 
Royal Institute of Technology (KTH) 
 SE-100 44 Stockholm 

The speech group at KTH has developed a number of speech technology tools for use in education of undergraduate students or researchers in the speech field. Many of these tools have been limited to a certain computer environment and the need for teacher guidance. During the last year we have started development work on a toolkit for spoken language technology that can be used over the Internet. The aim is to free the students from the need of using a particular computer at a particular time and place. We have created a speech technology toolkit that serves both as a basis and a framework in the creation spoken language systems. This toolkit is partly based on the software technology in our existing spoken dialogue system Waxholm. We have used the speech toolkit to build three web-based educational systems. We have developped an interactive tool for working with parametric speech synthesis. The tool facilitates editing of parameter tracks, and it provides real-time feedback of the synthesised speech. It serves as an interface to KTH's multilingual rule based synthesis system, and can be used to control a formant synthesiser as well as a 3-D "talking head". The tool has been used in research and education during the past two years. In our courses on speech technology we have an introductory section on basic phonetics and speech analysis. For this section we have developed a set of exercises in which students analyze their own speech in various ways. These exercises are accessed through web pages, in which simple speech analysis tools have been embedded as small applications (applets) dedicated to the task at hand. We have created an integrated lab environment for dialog systems that has been used in the courses on spoken language technology given at Masters level at three Universities in Sweden. In this environment, students are presented with a simple spoken dialogue application for searching in the web-based Yellow pages on selected topics using speech, presently in the Swedish language. The system is initialized with knowledge about streets, restaurants, hotels, museums and similar services. The aim of this work has been to put a fully functioning spoken dialogue system into the hands of the students as an instructional aid. They can test it themselves and are able to examine the system in detail. They are shown how to extend and develop the functionality. In this way, we hope to increase their understanding of the problems and issues involved and to spur their interest for this technology and its possibilities. The compete dialog system with speech recognition and synthesis as well as an interactive map can be used inside a web-browser using our plugins for audio and speech recognition.