Title:
ENCODING/QUANTIZING METHOD FOR AUDIO SIGNAL
Document Type and Number:
Japanese Patent JP3784993
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To suppress deterioration in sound quality by repeating processing for satisfying the restriction on the number of usable bits at every block and processing for satisfying the restriction on allowable error level.
SOLUTION: When the number of necessary bits becomes not more than the number of usable bits, all information bits amp[sfb] showing whether the value of a normalized coefficient sf[sfb] at every divided band changes or not in divided band sfb are initialized to '0'. The quantized error level in the divided areas sfb when an audio signal is quantized by a common normalized coefficient Csf and a normalized coefficient sf[sfb] at that time is obtained. When the divided area sfb where quantized error level becomes not less than the allowable level exists, the normalized coefficient sf[sfb] in the divided area sfb is increased by '1' and the information bit amp[sfb] is set to be '1'. Then, electronic error level is obtained again and processing is repeated until quantized error becomes less than the allowable error level on all the divided areas sfb.
Inventors:
Satoshi Araki
Application Number:
JP13075199A
Publication Date:
June 14, 2006
Filing Date:
May 12, 1999
Export Citation:
Assignee:
株式会社リコー
International Classes:
H03M7/30; G10L19/02; H04B1/66; G10L19/00; (IPC1-7): H03M7/30
Domestic Patent References:
| JP7154266A | ||||
| JP7058707A | ||||
| JP9214354A |
Foreign References:
| EP0967593B1 |
Other References:
P. Noll,High quality audio for multimedia: key technologies and MPEG standards,Global Telecommunications Conference,1999. GLOBECOM'99,IEEE,1999年,pp.2045-2050
Attorney, Agent or Firm:
Toshiro Kojima