METHOD OF PROCESSING AUDIO SIGNALS FOR IMPROVING THE QUALITY OF OUTPUT AUDIO SIGNAL WHICH IS TRANSFERRED TO SUBSCRIBER?S TERMINAL OVER NETWORK AND AUDIO SIGNAL PRE-PROCESSING APPARATUS OF ENABLING THE METHOD

摘要

An audio signal processing method for improving the output quality of an audio signal transmitted to a subscriber terminal through a communication network and an audio signal processing apparatus adopting the method are provided to improve the sound quality of the audio signal transmitted to the subscriber terminal by enhancing a probability capable of judging a frame of the audio signal as a voice interval in a voice codec of the communication network when transmitting the audio signal such as a ringback tone replacement sound to the subscriber terminal through the communication network. A voice codec encodes an audio signal and decodes the encoded audio signal. A codec module(350) transmits the decoded audio signal to a subscriber terminal through a communication network. The codec module(350) includes a VAD(Voice Activity Detection) unit(351) and a DTX(Discontinuous Transmission) unit(352). The VAD unit(351) judges whether one or more frames included in the audio signal are located in a voice interval or a mute interval. The DTX unit(352) transmits one or more parameters for the frames to the subscriber terminal according to the judged result.