| 摘要 |
PURPOSE: To suppress the degradation of S/N due to quantization by performing optimum quantization of input signals different by signal amplitude distributions. CONSTITUTION: A blocking means 1 which blocks the input signal to successively output a blocking signal x (n), a standard deviation operation means 2 which obtains a standard deviation σ of the amplitude distribution of the input signal constituting the blocking signal x (n), plural quantizing means 5 which is designed by probability density function different from each other to quantize the inputted signal, a selection control means 3 which outputs a select signal SQS to select one of plural quantizing means 5 based on the standard deviation σobtained by the standard deviation operation means 2 and the blocking signal x (n) corresponding to this standard derivation σ, and a switching means 4 which switches a signal route based on the select signal SQS to input the blocking signal x (n) to the quantizing means 5 corresponding to the select signal SQS are provided. |
