Patent Document ID: 9076436
Application ID: 13852300
Patent Status: 1

Claim One:
1. An apparatus for applying pitch features in automatic speech recognition, comprising: a computer processor associated with memory; a distribution evaluation module configured to evaluate a global distribution of pitch features of voiced frames in speech signals, and a global distribution of random values for unvoiced frames in speech signals; a normalization module configured to normalize the global distribution of the random values for unvoiced frames based on the global distribution of the pitch features of voiced frames, wherein the normalization module makes a standard deviation of the global distribution of the random values for unvoiced frames close to a standard deviation of the global distribution of the pitch features of voiced frames; a random value adjusting module configured to adjust the random values for unvoiced frames based on the normalized global distribution, so that the adjusted random values are assigned to unvoiced frames in speech signals as pitch features of the unvoiced frames; and a speech recognition module recognizing content of the speech signals based on the assigned pitch features of the unvoiced frames.