Diane Hirschfeld

A multilingual TTS system with less than 1 Mbyte footprint for embedded applications

Text-to-speech (TTS) systems have improved their quality to a large extent lately. This development has resulted in memory requirements of several megabytes that cannot be accepted in many applications, especially in embedded systems. Such applications are usually limited to a footprint of as much as 1 megabyte and require the processing power to be as low as possible. These requirements may be met if the text processing is changed from the usual data-driven algorithms to rule-based processing. Furthermore, the inventory (diphone inventory) should be as small as possible and should be stored in a compressed manner. This is demonstrated by a modified version of the Dresden speech synthesis system, DRESS, which is called microDRESS. Compared to the baseline system, microDRESS does not show essential quality losses apart from the influences of the telephone bandwidth which is appropriate for many embedded applications.

Pronunciation learning and foreign accent reduction by an audiovisual feedback system

Global integration and migration force people to learn additional languages. With respect to major languages, the acquisition is already initiated at primary school but according to their missing daily practice, many speakers keep a strong accent for longterm which may cause integration problems in new social or working environments. The possibility of later pronunciation improvements is limited since an experienced teacher and single education are required. Computer-assisted teaching methods have been established during the last decade. Common methods do either not include a distinct user feedback (vocabulary trainer playing a reference pattern) or widely rely on fully automatic methods (speech recognition regarding the target language) causing evaluation mistakes, in particular, across the border of language groups. The authors compiled an audiovisual database and set up an automatic system for the accent reduction (called azar) by using recordings of 11 native Russian speakers learning German and 10 native German reference speakers. The system feedback is given within a multi modal scenario.

Improving the Functionality of a Text-to-Speech System by Adding Morphological Knowledge

The quality-improvement of a speech synthesis system is tightly linked with the generation of natural sounding prosody. Reliable accentuation and structuring of the text based on syntactic knowledge are prerequisites for this goal. After the implementation of the morphological analysis system mpro, developed at IAI Saarbruecken, these functions are available in the text-to-speech system of the Dresden University of Technology.

Generation of adapted, speech-based user interfaces for home and building automation systems

Existing technologies in home and building automation system interface offer extensive possibilities to improve the individual life. However, especially seniors have large problems with the usually technology-centered user interfaces and avoid the technology. Instead, they are used to speech, which leaves speech-recognition and -synthesis suitable technologies for barrier-free interfaces. However, speech-based user interfaces require a large effort for adaptation, from the design of the user and system interfaces, to the adequate installation of devices. This paper introduces an approach to reduce this effort by a generative programming approach of the user and system interface.

Verbkey - A Single-Chip Speech Control for the Automobile Environment

The article deals with a novel speech recognizer technology which has the potential to overcome some problems of in-car speech control. The verbKEY recognizer bases on the Associative-Dynamic (ASD) algorithm which differs from established techniques as HMM or DTW. The speech recognition technology is designed to run on a 16 bit, fixed point DSP platform. It enables high recognition performance and robustness. At the same time, it is highly cost efficient due to its low memory consumption and its less calculation complexity. Typical applications such as dialling, word spotting or menu structures for the device control are processed by the continuous, real-time recognition engine with an accuracy higher 98% for a 20 words vocabulary. The article describes a hardware prototype for command & control applications and the measures taken to improve the robustness against environmental noises. Finally, the authors discuss some ergonomic aspects to obtain a higher level of traffic safety.