| 摘要 |
PURPOSE:To reduce an arithmetic quantity and shorten an arithmetic time and to reduce real-time processing and power consumption by finding a candidate to be delayed and limiting a decimal-point search section, and dividing a delay search, section by section. CONSTITUTION:Delay determining circuits 71A-71C determine section optimum integer delays A-C of respective delay sections A-C by using correlative values of respective signals. Then search section determining circuits 72A-72C determines search sections A-C set according to (e.g. two) samples before and after the respective optimum integer delays A-C. Then decimal delay code books 73A-73C find section optimum decimal-point delays of the respective search sections A-C by a closed loop. In this case, the respective processes can be performed in parallel. Then an optimum delay determining circuit 74 compares evaluation scales corresponding to the section optimum decimal-point delays of the respective search sections A-C to determine the best delay as a total optimum delay and generates an adaptive code sound source SA as a sound source signal corresponding to the optimum delay. |
