A signal encoding method for encoding input digital data by so-called high-efficiency encoding, wherein it is possible to suppress degradation in the sound quality in case of raising the compression ratio. The range of values of subband-based signal components for quantization to zero, to which a short codelength is given, is set so as to be larger. Consequently the ratio of the subband-based signal components quantized to values of a shorter codelength will become higher than if the subband-based signal components are quantized in such a manner as to minimize the total quantization error energy in each frequency band.
Adaptive subband scaling method and apparatus for quantization bit allocation in variable length perceptual coding