The present invention relates to a method and apparatus for obtaining
complete speech signals for speech recognition applications. In one
embodiment, the method continuously records an audio stream comprising a
sequence of frames to a circular buffer. When a user command to commence
or terminate speech recognition is received, the method obtains a number
of frames of the audio stream occurring before or after the user command
in order to identify an augmented audio signal for speech recognition
processing. In further embodiments, the method analyzes the augmented
audio signal in order to locate starting and ending speech endpoints that
bound at least a portion of speech to be processed for recognition. At
least one of the speech endpoints is located using a Hidden Markov Model.