| 摘要 |
PURPOSE:To faithfully transmit an important voice component so that the reproduced voice waveform does not have discontinuity in block borders after performing a complicated processing for each block for obtaining high privacy. CONSTITUTION:The linear prediction coefficient (LPC) of a voice signal Si is calculated in an LPC calculation part 2. An LPC inverted filter 3 performs the inverse filtering of the voice signal corresponding to the LPC and generates a remaining difference signal. A frequency component removing part 4 removes a frequency component with small electric power value for the spectrum envelope of the voice signal and arranges the remaining frequency component in a prescribed frequency section. An LPC conversion part 5 generates LPC information to be inserted in the prescribed frequency section obtained by removing a desirable frequency component. A synthesizing part 6 synthesizes the remaining difference component and the LPC information. |
