Title:
【発明の名称】ディジタル信号符号化方法
Document Type and Number:
Japanese Patent JP2861238
Kind Code:
B2
Abstract:
A digital signal encoding apparatus includes a circuit (10) in which an allowable noise level is set for each of plural frequency bands of an input digital signal on the basis of the energy from one band to another, and a quantization circuit (24) in which components of the signal in each of the frequency bands are quantized with a number of bits corresponding to the level of the difference between the energy of each frequency band and the allowable noise level. In the allowable noise level setting circuit (10), the allowable noise level of a particular frequency band is set on the basis of the energy of that particular frequency band and that of another frequency band, and a non-linear relationship is provided between the energy and the allowable noise level to enable data compression which is more intensive and more agreeable to the ear. Also, even if the input digital signal is preemphasized (20), the allowable noise level setting is made on the basis of a signal corrected (22) for preemphasis, so that quantization may be performed in a manner free from the effects of preemphasis.
Inventors:
AKAGIRI KENZO
Application Number:
JP10304590A
Publication Date:
February 24, 1999
Filing Date:
April 20, 1990
Export Citation:
Assignee:
SONII KK
International Classes:
G10L19/038; G06T9/00; G10L19/035; H03H15/00; H03H17/00; H03H21/00; H03M7/30; H04B1/66; H04B3/04; (IPC1-7): H03M7/30; G10L9/18; H03H17/00
Domestic Patent References:
| JP3117920A | ||||
| JP3117921A | ||||
| JP6330031A | ||||
| JP63299419A |
Other References:
Ｐｒｏｃｅｅｄｉｎｇｓ．ＩＥＥＥ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｃｏｎｆｅｒｅｎｃｅ ｏｒ Ａｃｏｕｓｔｉｃｓ，Ｓｐｅｅｃｈ ａｎｄ Ｓｉｇｎａｌ Ｐｒｏｃｅｓｓｉｎｇ （１９８８）Ｖｏｌ．５，ｐ．２５２４−２５２７
Ｐｒｏｃｅｅｄｉｎｇｓ．ＩＥＥＥ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｃｏｎｆｅｒｅｎｃｅ ｏｒ Ａｃｏｕｓｔｉｃｓ，Ｓｐｅｅｃｈ ａｎｄ Ｓｉｇｎａｌ Ｐｒｏｃｅｓｓｉｎｇ （１９８９）Ｖｏｌ．３，ｐ．１９９３−１９９６
Ｐｒｏｃｅｅｄｉｎｇｓ．ＩＥＥＥ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｃｏｎｆｅｒｅｎｃｅ ｏｒ Ａｃｏｕｓｔｉｃｓ，Ｓｐｅｅｃｈ ａｎｄ Ｓｉｇｎａｌ Ｐｒｏｃｅｓｓｉｎｇ （１９８９）Ｖｏｌ．３，ｐ．１９９３−１９９６
Attorney, Agent or Firm:
Akira Koike (2 outside)