AUDIO SIGNAL CODING DEVICE AND AUDIO SIGNAL CODING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an audio signal coding device and an audio signal coding method which are capable of reducing the number of times of a quantization loop required for reducing the number of quantization bits to the number of bits allowing quantization or smaller to shorten the time required for quantization processing.SOLUTION: The audio signal coding device divides a frequency mdct(k) obtained from an input digital signal (x(n)) to a plurality of bands and performs scaling and quantization based on scale factors scalefactor(sfb) of respective bands and a common scale value CommonScale common to the plurality of bands to code the quantized frequency spectrum. The audio signal coding device includes: a number-of-bands determination unit 14 which calculates the number of coded bands (band) for coding the quantized frequency spectrum; and a common scale estimation unit 15 which estimates the common scale value in accordance with the number of coded bands.