METHOD AND DEVICE FOR ENCODING INFORMATION AND METHOD AND DEVICE FOR DECODING INFORMATION

摘要

A frequency component separating circuit (701) converts an input waveform signal into frequency components. The frequency components are normalized, quantized, and encoded by a normalizing/quantizing circuit (702) and a code string generating circuit (703). By use of a processed-band limiting circuit (704), the QMF operation for the unnecessary band is omitted. Therefore the number of operations necessary for the filter operation is decreased and high-speed operation is enabled. Further the work area necessary for the filter operation can be decreased. The filter operation is thus simplified in conformity with, for example, the quality of reproduced signals required, and the size of the encoding and decoding devices can be lessened.