| 摘要 |
PURPOSE:To control a quantization step size with high accuracy with simple constitution by converting an output data of a quantization circuit into a parallel variable length coding data and a code length data and then converting the data into a serial variable length coding data. CONSTITUTION:A parallel output data from a requantization circuit 24 is converted into a parallel variable length coding data DT and a code length data DL and stored in buffer memory circuits 62, 64 and then converted again into a serial variable length coding data DVLC, then a parallel serial conversion circuit 66 is in operation at a low speed. ln this case, a counter circuit 68 detects a difference of the data quantity between the parallel variable length coding data DT from the 1st conversion table 60 and the serial variable length coding data DVLC outputted from the transmission buffer circuit 33 to select the quantization step size based on the result of detection. Thus, the requantization circuit is controlled with simple constitution and high accuracy. |
