METHOD AND DEVICE FOR HIGH EFFICIENCY ENCODING, METHOD AND DEVICE FOR HIGH FREQUENCY DECODING, AND TRANSMISSION MEDIUM

摘要

PURPOSE: To improve the encoding efficiency or not only main information but also auxiliary information and to secure sufficient freedom for the expressing method of auxiliary information to satisfactorily encode information. CONSTITUTION: A conversion circuit 61 which converts an input signal to a frequency component, a signal component separation circuit 62 which separates this frequency component into a tone component consisting of only the signal component in a specific band to be encoded together with band designating information and a noise component which is normalized and quantized by prescribed encoding units and is encoded together with quantization step number information, a tone component encoding circuit 63 which encodes the tone component, and a noise component encoding circuit 64 which encodes the noise component are provided. Quantization step number information of the noise component is encoded to a quantization precision information code expressed on the high band side with a smaller number of bits than that on the low band side.