| 摘要 |
PURPOSE:To provide the scale detecting device which can detects a given acoustic signal even when the acoustic signal has an intermediate scale between respective fixed scales. CONSTITUTION:The input acoustic signal is digitally filtered to two mutually adjacent fixed scales which are close to the actual scale of the input acoustic signal; and the scale which has a large envelope value between the two scales is denoted as Max and the scale which has a small envelope value is denoted as Second. The low scale between those Max and Second is denoted as Low and the high scale is denoted as High (step Q1); and the address of a data table ROM for intermediate-sound detection is set to Low (step Q2). Then the ratio of the envelope of those Low and High is calculated and the offset of the intermediate-sound data is obtained from the value (step Q3). The detected scale is set to Low and bend data is set to a shift quantity from the Low based upon table data (step S4). The scale shifted from the detected scale by this shift quantity is detected as the scale of the actual input acoustic signal. |
