Encoding method and apparatus, and decoding method and apparatus

摘要

In a decoding apparatus ( 30 ), power compensation spectrum generation/composition units ( 37 ₁ to 37 ₄) adjust power of power compensation spectrums PCSP based on quantization accuracy information, normalization coefficients, gain control information, and power adjustment information. Then, power of the spectrums SP is compensated by replacing spectrums SP being equal to or smaller than a threshold with the power-adjusted power compensation spectrums PCSP, or by adding the power-adjusted power compensation spectrums PCSP to the spectrums SP.