Speech Coding Based on Orthogonal and Biorthogonal Wavelet

The main objective of speech compression is to reduce the bits rate of speech for communication or storage without significant loss of its intelligibility. Wavelet based speech coding is a new technique used for speech compression. The main issue regarding wavelet based speech coding is to choose optimal wavelet to transform the speech signal. In this experiment we use two types of wavelet such as orthogonal and biorthogonal wavelets to transform the speech signal. Speech data base for this experiment is created in Malayalam, one of the South Indian languages. Birage-Massart strategies based thresholding is applied to make maximum feature vector coefficients to zero. Run length encoding algorithm is used to encode the threshold coefficient. Performance of this experiment is evaluated in terms of NRMSE, SNR, PSNR, RSE MOS and in terms of compression percentage.