Some ways to classify a speech recognition system and speech quality have been described. Generally, a recognition system can only cope with some of the parameters in the ``difficult'' region, and must yield towards the other conditions. For instance, a large vocabulary speaker independent continuous speech recogniser only performs well on undisturbed, read speech of a known domain (vocabulary and grammar ), and a speaker-independent telephone speech real-time recognition system may be designed to recognise digits only. In this way, the capabilities of a particular recogniser with respect to all the conditions define a capability profile.
It is a very good idea to realise that the requirements of a
particular application define a similar application
requirement profile which is generally different from the
capability profile of most recognition systems.
Before you choose your set of recognisers to assess, define the requirements of the application, if any, and compare those with the specifications of the recognition systems.