Method and apparatus for voice control of a computer

Apparatus for voice control of program execution in a computer in which a program is being instituted, said apparatus comprising:

• operator input means for receiving spoken speech from an operator in the form of an audible voice command affecting the operation of the computer program and generating an input analog speech signal representative of the voice command;
• signal conditioning means for receiving the input analog speech signal from said operator input means and providing word-discrimination information as an output based upon the zero-crossing rate of the input analog speech signal, said signal conditioning means being effective to divide the input analog speech signal into a plurality of discrete speech signal portions and to produce a waveform sequence for each speech signal portion alternating between plus and minus polarity signs to define a zero-crossing signal from which a zero-crossing count can be obtained;
• event counter means operably associated with the output of said signal conditioning means for detecting signal transitions in the waveform sequences between plus and minus polarity signs and maintaining a zero-crossing count of each detected polarity transition in the waveform sequences corresponding to each of the speech signal portions as provided by said signal conditioning means;
• memory means storing a plurality of reference templates of digital speech data respectively respresentative of individual words comprising a vocabulary of voice commands each of said reference templates being defined by a plurality of binary segments of one bit each having a logic state of alternative high and low levels corresponding to respective thresholds related to high and low zero-crossing counts;
• processing means operably connected to said event counter means and said memory means, said processing means being responsive to the output of said event counter means to interrupt the execution of the computer program upon detection of a predetermined condition relative to the zero-crossing count maintained by said event counter means and including comparator means for comparing the zero-crossing count attributable to each speech signal portion of the input analog speech signal as obtained by said event counter means with said plurality of reference templates stored in said memory means to determine the particular reference template which has the same sequence of logic states assigned to the one-bit binary segments for portions of the input analog speech signal as are reflected by the zero-crossing count of such portions of the input analog speech signal as a recognition of the particular voice command provided by the spoken speech of the operator;
• said processing means further including means to execute the recognized voice command as represented by said particular reference template during the interruption of the execution of the program;
• and
• means responsive to the execution of the recognized voice command by said executing means for resuming execution of said program being run in the computer.