CODING METHOD AND DECODING METHOD OF ACOUSTIC SIGNAL

摘要

PROBLEM TO BE SOLVED: To make decoding possible even when part of information is lost in a network where the usable bit rate is variable. SOLUTION: A first prediction coder 41 codes input voice to obtain the difference signal (43) between its decoding signal and the input voice. It gives gain to the noise waveform vector to supply as a driving vector to a synthesizing filter 14b, selects the noise vector and its gain to mininmize the distortion power of the synthesizing signal to the difference signal. The filtering coefficient of the synthesizing filter in the first coder 41 is set in the filter 14b.