| 摘要 |
PURPOSE:To quicken the coding processing and the decoding processing by outputting a prediction coding code selectively when an input sample value is inputted selectively to plural memory circuits including different lookup tables. CONSTITUTION:The characteristic of a quantizer and an inverse quantizer differs from ROMs I-III 16-18. When switches 15, 19, 21 are switched, a 4-bit DPCM code Yi according to the quantization characteristic of any of the ROM-I 16-ROMIII18 is outputted through the switch 19 and fed to a synchronizing addition circuit 12. Moreover, an 8-bit local decoding value according to any quantizing and inverse quantization characteristic of the ROMs is fed to a D flip-flop FF 14 through the switch 21 and the output of the D FF 14 is inputted to each ROM as a prediction value of the succeeding sampling. On the other hand, the synchronizing addition circuit 12 adds an ID data including a synchronizing data and output information of a keyboard 23 to plural DPCM codes. Thus, high speed processing is attained. |
