| 摘要 |
PURPOSE:To simplify the constitution of device and to prevent the increase in quantized noise due to forecast encoding and decoding, by quantizing a forecast signal operated with higher accuracy than that for quantization of an input signal from a decoded signal, with the same degree of accuracy. CONSTITUTION:A code signal transmitted from a transmission line is transmitted from an input terminal 12 of a forecast encoding device to a code conversion circuit 13, and a quantized forecast error signal corresponding to the respective code is inputted to an adder 14. A decoded signal obtained at the output of the adder 14 is applied to an adder 15, where a signal of a DC component having 0.5 amplitude produced at a DC component generating circuit 16 is added to a decoded signal and transmitted to a forecast device 17, to obtain the forecast signal added with the DC component for the output of the forecast device 17 having the same forecast characteristics as a forecast device 8 of the encoding device. This signal is rounded off for the fractions at a round-off circuit 18 to obtain the forecast signal having the same accuracy for quantization as that for a digital video input signal. |
