Data and restore device data secret apparatus, image forming apparatus, data secret of method, a program

摘要

Disclosed is a data concealing apparatus, which makes it possible to heighten the strength of the encryption processing that employs such the data cryptography method in which the encryption of compressed image data is achieved by destroying a part of the compressed image data concerned. The data concealing apparatus includes: an establishing section to establish a data size of a portion of compressed data in a changeable manner; a cryptography key extracting section to extract the portion of compressed data from the compressed data as the cryptography key data, while making a data size of the cryptography key data coincide with the data size established by the establishing section; and an encrypting section to encrypt the compressed data by replacing the portion of compressed data, extracted as the cryptography key data by the cryptography key extracting section, with certain data being different from the cryptography key data.