A New Speech Waveform Coding Based on the Nonuniform Sampling Method with Separated to High-Low Band
Myung-Jin Bae, Joo-Hun Lee, Sungbin Im, Won–Cheol Lee · The Journal of the Acoustical Society of Korea · 1995
To reduce the redundancy within samples that resulted from uniform sampling method, nonuniform sampling or nonredundant-sample coding methods can be considered. However, it is well known that when conventional nonuniform sampling methods are applied directly to speech signal, the required amount of data is comparable to or mure than that by uniform sampling method like PCM. To overcome this problem, a new nonuniform sampling method is proposed, in which nonuniform sampling is applied to the low-pass filtered speech signal and higher band is compensated by 8 colored Gaussian random noise with various noise levels. By this method, speech signal waveform can be encoded by 1.8 times larger compression ratio than the conventional nonuniform sampling method.