Aculab’s TTS software is designed for use in telephony applications, setting a standard for accuracy and channel count. Our host based TTS is a fully scalable, fast and accurate, concatenative speech synthesis system that has a small memory footprint and offers an exceptionally high channel count using a client/server architecture.

Aculab TTS works in conjunction with Prosody product options, which are used for audio replay and the simultaneous use of other media processing resources.

Developers are, therefore, able to enhance the performance of their telephony applications, combining TTS with automatic speech recognition (ASR) and separate media processing algorithms, through the generic Aculab API. When used with Prosody media processing resources, Aculab TTS is available under a cost free licence, from software downloads.

Aculab TTS includes an email pre-processor and a lexicon customisation tool. One product build is offered providing multiple language support. See features summary for details of languages available and software downloads for details of operating systems supported.

Speech technology
With the recent improvements in speech and language technology, innovative and sophisticated solutions for a range of markets can be produced using Aculab TTS and Prosody. For example, electronically formatted text messages can be retrieved and heard by telephoning an integrated messaging service. This type of service is ideal for people on the move who need immediate access to their email messages whilst out of the office. When using TTS in a contact centre environment, information can be read out to callers, allowing an organisation to offer improved customer service without increasing staff numbers.

TTS has been specifically designed for use in telephony applications that require spoken output and where the information to be read out is either frequently updated or too extensive to record.

It is unique in that its development has taken into account all of the additional constraints that the telephone networks impose, for example, narrow bandwidth, noisy listening conditions and high channel requirements. As a result, Aculab TTS produces extremely consistent and intelligible telephone speech, even for prolonged passages of synthesised text.

TTS architecture
Aculab TTS is used with Prosody cards in PCI or cPCI card formats that provide audio via an E1 or T1 network line interface. It can also be used with Prosody S as the TTS software is compatible with any media processing firmware that supports 64kbit/s replay. Replay (or playback) may be combined with other media processing algorithms, such as echo cancellation and recording to enable barge-in for applications using ASR.

This means that developers benefit from the flexible combination of speech technologies and Prosody to enable the construction of resilient, high performance, scalable systems.