Speech recognition in the office: how the technology supports dictation

Automatic speech recognition by computer, in real-time and using only an input audio signal, has been developed over the last two decades to the point where it is useful for a number of practical applications, such as telephone enquiry services and office dictation. The purpose of talking to a computer is first examined and the inherent reasons for the difficulty of understanding speech are suggested. Three specific problems in the recognition process are highlighted: data rate reduction, speaker variability and application domain dependence. The currently successful methodology used in speech recognition systems is described in non-technical terms. The principal processes required for real-time automatic speech recognition are introduced, and the need for adaption and customization discussed. Some suggestions for the directions of future research and applications are given.