ENCRYPTION PROCESSING APPARATUS, ENCRYPTION METHOD, DECRYPTION PROCESSING APPARATUS, DECRYPTION METHOD AND DATA STRUCTURE

摘要

To allow encryption by setting conditions of decryption variously. Encrypted data obtained by encrypting subject data has header data 501, basic condition data 502, encrypted condition data 503 and encrypted cut data 504. The basic condition data 502 includes data on a condition for allowing or prohibiting decryption of the encrypted condition data 503. A decryption processing apparatus decrypts only the encrypted condition data of which decryption is allowed by the basic condition data 502 so as to render it as condition data. The condition data includes data on a condition for allowing or prohibiting decryption of the encrypted cut data. The decryption processing apparatus decrypts only the encrypted cut data 504 of which decryption is allowed by the encrypted condition data 503.