Patent ID: 8311814
Filing Date: 2012-11-13
Classification: G10L

Abstract:
1. A method, comprising: a processor receiving a plurality of audio samples, the audio samples defining a sampled signal segment; the processor creating a signal amplitude waveform defined by the audio samples; the processor determining a trend in the signal amplitude waveform by comparing a first amplitude of an audio sample with a second amplitude of a previous audio sample; the processor identifying turning points in the signal amplitude waveform, wherein the turning points occur when the trend changes from positive to negative or from negative to positive; the processor determining an amplitude for each of the turning points; the processor determining whether the amplitudes of the identified turning points are representative of a signal of a substantially fixed power level; and when the amplitudes of the identified turning points are representative of a signal of a substantially fixed power level, the processor deeming the sampled signal segment to comprise an active signal, wherein the turning points are not zero crossings, and wherein, when the identified turning points are representative of a signal of a substantially fixed power level, the sampled signal segment is deemed to include a progress tone.