| 摘要 |
PURPOSE:To provide a sound input device which can save a memory by equipping it with a function to select optimum input level. CONSTITUTION:In each input circuit 1', input sound signals V are amplified with different amplification factors, and A/D conversion is performed, and the signals from the start of input to time T are stored as front sound signals F in a front memory 30'. A gain selection control circuit 2' selects a signal that it judges to be on optimum level out of front sound selection signals F1-Fn, and informs it by a gain selection signal S. A selection signal 4 selects one out of sound digital signals D1-Dn by the selection signal S, and stores the signal from after passage of time T to the finish of sound input as a rear sound signal B in a rear memory 5. A feature abstracting part 3' selects one out of front sound signals F1-Fn, and adds a rear sound signal stored in the rear memory 5 to the rear of this selected front memory signal so as to abstract features. |
