A facial feature communications interface for the non-vocal

A viable communications interface for the nonvocal handicapped that is a by-product of recent face recognition research is described. The system uses either the Karhunen-Loeve transform (KLT) or the discrete cosine transform (DCT) to encode video camera images on a subject's face. The encoding differentiates among three expressions: tongue out which is classified as 'yes'; mouth open, which is classified as 'no'; and mouth closed, which is classified as 'null'. A review of the theory of the KLT and DCT is included.<
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