| 摘要 |
PROBLEM TO BE SOLVED: To provide an audio bit rate converting method of lowering a bit rate while suppressing deterioration in sound quality by operating orthogonal transformation coefficients. SOLUTION: The audio bit rate converting method and device includes a procedure for making an increment correction of a global gain of a frame of attention, a procedure for making decrement corrections of orthogonal transformation coefficients of all scale factor bands of the frame of attention together along with the increment correction of the global gain, a procedure for repeating the increment correction of the global gain and the decrement corrections of the orthogonal transformation coefficients, a procedure for making an increment correction of an orthogonal transformation coefficient of a scale factor band which is not zero in the frame of attention until a necessary bit amount and a target bit amount of the frame of attention have second large/small relation, and a procedure for making a decrement correction of the scale factor value of the scale factor band whose orthogonal transformation coefficient is increased and corrected. COPYRIGHT: (C)2008,JPO&INPIT
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