| 摘要 |
PURPOSE:To omit a control signal line without degrading the quality of sound by transmitting a control signal together with a difference signal and assigning a bit having minimum change in the absolute value of the difference signal as a bit for the control signal. CONSTITUTION:A quantizing circuit 11 quantizes the difference between a sampled sound signal input and an output of a forecasting circuit 13 and a coding circuit 12 encodes an output of the quantizing circuit 11. The forecasting circuit 13 forms a new forecasting signal based on a forecasting signal before one sample and an output of a decoding circuit 18. Quantizing step generating circuits 14, 15 form a quantizing step size DELTAi based on the output of a control signal addition circuit 19. Decoding circuits 16, 18 decode a coded signal. The control signal addition circuit 19 replaces a minimum quantized bit of a coded difference signal at a prescribed sampling point into a control bit. A control signal separating circuit 20 separates the control signal out of the coded signal. |
