| 摘要 |
PURPOSE:To improve the secrecy of documents by coding the pictures with high efficiency that are converted into a digital style after the photoelectric transducing, sampling and quantization and storing these codes in a file after ciphering them. CONSTITUTION:The information on a document 3 is scanned by a scanner 4 and a digital picture 51 of the input document is outputted after the photoelectric transducing, sampling and quantization. At the same time, the picture control information 52 is obtained as the output of the scanner 4. Both the picture 51 and the information 52 are stored in a buffer memory 5. Then the picture 51 is converted into a Huffman MH code 54 by an improved MH coding processor 7 and stored in the memory 5. A control part 2 adds the random numbers to the MH code data 54 to produce the random number addition data 55. Both the data 55 and the information 52 are converted into the cipher data 56 by a ciphering processor circuit 8 and stored in the memory 5. Then the part 2 stores the data 56 and the directory information 53 in a file 9. |
