SPEECH DECODING APPARATUS, SPEECH ENCODING APPARATUS, AND LOST FRAME CONCEALMENT METHOD

摘要

Disclosed is a sound decoding device capable of improving the lost frame compensation performance and improving quality of the decoded sound. In this device, a rise frame sound source compensation unit (154) generates a compensation sound source signal when the current frame is a lost frame and a rise frame. An average sound source pattern update unit (156) updates the average sound source pattern held in an average sound source pattern holding unit (157) over a plurality of frames. When a frame is lost, an LPC synthesis unit (159) performs LPC synthesis on a decoded sound source signal by using the compensation sound source signal inputted via a switching unit (158) and a decoded LPC parameter from an LPC decoding unit (152) and outputs the compensation decoded sound signal.