ENCODING METHOD, DECODING METHOD, ENCODING-DECODING METHOD, ENCODER, DECODER, AND ENCODER-DECODER

摘要

At an encoder 1, an input signal delivered to an input terminal 100 is divided into 32 subband signals by an analysis filter bank 101 to determine scale factors indicating magnification which normalizes respective subband signals by a scaling section 102 to determine the numbers of allocation bits of the respective subband signals by a bit allocation section 103 in dependency upon their scale factors to quantize the respective subband signals by the determined numbers of allocation bits by a quantizing section 104 to encode the respective quantized subband signals and the scale factors with respect to the respective subband signals. On the other hand, at a decoder 2, an inverse quantizing section 108 is used to determine the numbers of allocation bits by using scale factors included in the encoded signal with respect to the respective subband signals of the encoded signal to inverse-quantize the subband signals to judge whether or not scale factors are preserved with respect to the respective inverse-quantized subband signals to carry out, for a second time, inverse quantization with respect to the subband signals where no scale factor is preserved so as to preserve scale factors.