Abstract: A speech synthesizer has a language generator for generating a text-form utterance from input semantic information and a text-to-speech converter for converting the text-from utterance into speech form. The overall quality of the speech-form utterance produced by the text-to-speech converter, is assessed and if judged inadequate, the language generator is triggered to produce a new version of the text-form utterance. The assessment of the overall quality of the speech form utterance is preferably effected by a classifier fed with feature values generated during the conversion process operated by the text-to-speech converter.

Abstract: In a distributed voice recognition system, a back-end pattern matching unit 27 can be informed of voice activity detection information as developed through use of a back-end voice activity detector 25. Although no specific voice activity detection information is developed or forwarded by the front-end of the system, precursor information as developed at the back-end can be used by the voice activity detector to nevertheless ascertain with relative accuracy the presence or absence of voice in a given set of corresponding voice recognition features as developed by the front-end of the system.

Abstract: A portable reading machine has a scanner for scanning an image comprising text. The scanner has a scanning area occupying a maximum width and an active width defined by a scanning width limiting mechanism adjustable to a preselected width. A photoreceptive element forms an electronic representation of a portion of the image within the active width. The electronic representation is converted to a digital character string corresponding to the active image text. A speech system outputs the digital character string as ordinary spoken language voiced through a speaker or headset.