| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital data encoding device which uses one kind of quantizer to reduce the quantization noise of the maximum spectrum in each frequency band at the time of quantization and enables spectrum levels in the frequency bands after the quantization except the maximum spectrum to be made lower than conventional quantization values. SOLUTION: A digital data encoding device 1 provided with; a time frequency conversion part 3 for converting an audio signal to a frequency area; a scale factor generation part 9 for generating scale factors relating maximum spectrums of spectrums converted for a plurality of frequency bands respectively; a number of quantization bits calculation part 6 for calculating the number of quantization bits for each frequency band; and a quantization part 7 for quantizing the spectrums to quantize them by using the scale factors and the numbers of quantization bits is provided with a spectrum data correction part 10 which corrects the spectrums by multiplying them by constants calculated on the basis of scale factors and the numbers of quantization bits. COPYRIGHT: (C)2005,JPO&NCIPI
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