| 摘要 |
A code table apparatus for a variable length decoder (VLD) is disclosed. The code table apparatus is connected to a barrel shifter to obtain an input code which consists of a code word portion and a sign bit. The code table apparatus comprises a coefficient table for generating a level code and a length code by the code word portion, and a mask circuit for generating a sign bit by a logic operation of the input code and the length code. The coefficient table can decode input codes with opposite sign bits, thus reducing the dimensions of the coefficient table as well as the VLD. Furthermore, since the dimensions of the coefficient table are reduced, the operation time delay of the DCT coefficient table can be shorter, thus improving the performance of the VLD. |
