CORD EXCITATION LINEARITY PREDICTION VOCODER USING FALSE SEARCH

摘要

PURPOSE: To improve the response during audio transition such as an unvoiced area to a voiced area by using virtual search of a code book including the candidate exciting vector of a code exciting linear prediction vocoder. CONSTITUTION: A LPC(linear predictive coding) analyzer 101 responds to an inputted voice, a LPC coefficient is determined, an entry from a code book on probability base 105 approximating a voice to the frame best and an adaptive code book 104 together with a scaling coefficient and the excited coefficient information is sent to a decoder 151 through a path 145 by means of an encoder 109. A probability generator 153 and an adaptive generator 154 respond to the entry of the code book and the scaling coefficient, the calculated excited information is reproduced and a LPC filter 157 determined by the LPC coefficient is excited for exciting the voice by using the excited information.