1. A method of discriminating speech from voice-band data in a communication network, comprising: calculating a self similarity ratio value, representing a periodicity characteristic, and an autocorrelation coefficient value, representing a spectral characteristic, for an input signal segment, wherein calculating the self similarity ratio value includes calculating a plurality of different self similarity ratio values and selecting the highest one of the plurality of different self similarity ratio values as the calculated self similarity ratio value; and determining whether said input signal segment is speech or voice-band data based on said at least one of said self similarity value and said autocorrelation coefficient value.
1. A method of discriminating speech from voice-band data in a communication network, comprising: calculating a self similarity ratio value, representing a periodicity characteristic, and an autocorrelation coefficient value, representing a spectral characteristic, for an input signal segment, wherein calculating the self similarity ratio value includes calculating a plurality of different self similarity ratio values and selecting the highest one of the plurality of different self similarity ratio values as the calculated self similarity ratio value; and determining whether said input signal segment is speech or voice-band data based on said at least one of said self similarity value and said autocorrelation coefficient value. 3. The method of claim 1 , wherein said self similarity ratio is calculated based on more than one sample.