| 摘要 |
PURPOSE:To reduce the number of access times and to decode MH codes in high speed, by decoding white modified Hoffmann MH codes in the number of access times less than that of coding words by 3 times and decoding black MH codes with the number of access times less than that of code length by one time. CONSTITUTION:A decoder for the MH codes is provided with a CPU1 comprising microprocessor, and a program memory 3 and a table memory 5 storing hash table and binary tree table are connected to the CPU1. The input side is provided with an I/O 3 connected to an FIFO2 inputting the MH codes and the output side is provided with a run length RL circut 7 and a line memory 8 connected to an I/O 6. Bits of the white MH codes, from the head to the 4th bit, are accessed with the hash table and the 5th bit and succeeding are accessed with the tree search table. In case of the black MH codes, bits from the head to the 2nd bit are accessed with the hash table and the 3rd bit and succeeding are accessed by the tree search table. |
