TRANSCEIVER FOR ENCODING AND DECODING VOICE USING ADDITIONAL BIT ASSIGNMENT METHOD

摘要

PURPOSE: A transceiver for encoding and decoding voice using an additional bit assignment method is provided to offer a high-quality voice service by assigning only additional bits admitted in a system using a voice encoder used in an old voice processing system. CONSTITUTION: A standard voice encoding unit(102) classifies an inputted voice signal into spectrum information indicating a vocal tract transfer function and an excitation signal component, and models and quantizes spectrum information and the excitation signal component. The standard voice encoding unit(102) performs the standard encoding of the quantized signal, and generates a standard-encoded bit series. A quality improvement encoding unit(103) obtains an error between a signal in which spectrum information is not quantized and a signal in which spectrum information is quantized by the standard voice encoding unit(102). The quality improvement encoding unit(103) obtains an error between a signal in which the excitation signal component is not quantized and a signal in which the excitation signal component is quantized. The quality improvement encoding unit(103) additionally quantizes the obtained errors, and generates an encoded bit series. A multiplexing unit(104) multiplexes the bit series obtained in the standard voice encoding unit(102) and the quality improvement encoding unit(103), and transmits the multiplexed bit series.