| 摘要 |
PURPOSE:To reduce data quantity of generated codes and to decrease the storage capacity of a coding table as required. CONSTITUTION:A difference of DCT coefficients in the unit of a block is coded. When a comparator 12 decides the difference of the DCT coefficients to be smaller than a minimum coefficient, a selector 16 is used to replace the difference of the DCT coefficients with the minimum coefficient. When a comparator 14 decides the difference of the DCT coefficients to be larger than a maximum coefficient, the difference of the DCT coefficients are replaced with the maximum coefficient. Since a range of DCT coefficients to be coded is made narrow, the information quantity allocated to codes is reduced and generated data quantity is decreased. |
