PhySyQX: A database for physiological evaluation of synthesised speech quality-of-experience

A product´s success in the market can be predicted based on the Quality-of-Experience (QoE) it offers to its users. With the burgeoning market for text-to-speech (TTS) systems, it has become extremely important to characterise new TTS systems in terms of their QoE. To this end, many objective models for quality estimation have been developed. These state-of-the art models are developed considering the system and contextual factors which influence the users´ experience. Such models generally lack inputs from human factors, as these are not directly observable and are manifested inside users´ brains. Therefore, in this study a multi-modal database was developed for neuro-physiological identification of the human factors which influence user perceived QoE and also to probe into the users´ internal quality formation processes. It is hoped that the database will help improve the pre-existing models for quality estimation. The database utilizes neuro-physiological tools, such as electroencephalography and functional near infrared spectroscopy, to record users´ brain activity while experiencing synthesised speech produced from various commercially available TTS systems. Moreover, an extensive analysis of participants´ ratings has been reported in the paper. Also, the database has been made publicly available online to encourage other researchers to utilize the neuro-physiological insights while developing new quality estimation algorithms.