CPC G10L 25/09 (2013.01) [G10L 15/02 (2013.01); G10L 15/10 (2013.01)] | 15 Claims |
1. An apparatus comprising:
a processing device programmed to:
receive an original audio signal;
add a high-frequency signal to the original audio signal to obtain an audio signal, the high-frequency signal having a frequency and amplitude selected to add zero crossings to portions of the original audio signal including only ambient noise without speech;
generate a pulse stream according to zero crossings detected in the audio signal;
generate a pulse density stream according to the pulse stream indicating frequency of occurrence of pulses in the pulse stream over time;
evaluating the pulse density stream with respect to a threshold condition; and
identifying speech portions of the audio signal corresponding to portions of the pulse density stream meeting the threshold condition.
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