摘要 |
Good sound quality as perceived by the ear is obtained even with few information bits. A shape quantizer (111) is comprised of an interval search unit (121) which searches and encodes the pulses in each band of a plurality of divisions of the specified search interval, and a full search unit (122) which searches for pulses over the entire search interval, and quantizes the shape of the input spectrum at the positions and the polarities of a small number of pulses. The interval search unit (121) encodes a pulse searched for in a higher band than the specified frequency with fewer bits than a pulse searched for in another band. The full search unit (122) encodes the pulses positioned in a higher band than the specified frequency with fewer bits than the other pulses. A gain quantizer (112) calculates and quantizes in each band the gain of a pulse searched for by the shaper quantizer (111).
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