Method and apparatus for determining a likely word sequence from labels generated by an acoustic processor.

摘要

The present invention addresses the problem of determining, in a speech recognition context, a likely sequence or path of words from a plurality of word paths given a string of labels that are generated at successive intervals. The invention features multiple stack decoding and a unique strategy for extending one word path at a time without undue reliance on word path length. With multiple stack decoding, a stack is associated with each label of the label string. Word paths that most likely end at a given label are assigned to the stack corresponding to the given label and are ordered according to likelihood at the given label. The strategy of deciding which word path to extend includes the forming of a likelihood envelope against which the word paths are compared to determine if a word path is sufficiently likely to be extended. From among the word paths that are found to be extendible, the word path of highest likelihood in the earliest stack --i.e. the shortest most likely word path-- is selected for extension. After a word path is extended, it is deleted from its stack and the word paths extended therefrom are entered into appropriate stacks.