| 摘要 |
PURPOSE:To obtain a decoding signal with high quality by performing encoding also on the change of the leading edge part of a signal and the time of a cyclical part in addition to the cyclical part. CONSTITUTION:The leading position t5 and the shape of envelope of the signal converted to a digital signal by an A/D converter 1 are detected by a detector 2. Simultaneously, one cycle time t0 in which a loop can be taken is detected from the cyclical property of the signal by a detector 3 by utilizing a zero cross point, etc. The signal of constant time t1 (t1: multiple times the t0) decided in advance in a controller 4 is taken out by a switch 7 as a first part, and is encoded by an encoder 5. The signal of one cycle time t0 or plural times the time is take out of a remaining second part by a switch 8 as a representative part, and is encoded by an encoder 6. Thereby, the decoding signal with high quality can be obtained. |
