Watermark detector

• Main Authors: J.C. TALSTRA, J.P.M.G. LINNARTZ, P.J. LENOIR
• Format: Patent
• Language: English
• Published: 01.01.2003
• Edition: 7
• Subjects: ADVERTISING; CALCULATING; CODING OR CIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHERPURPOSES INVOLVING THE NEED FOR SECRECY; COMPUTING; COUNTING; CRYPTOGRAPHY; DISPLAY; EDUCATION; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRIC DIGITAL DATA PROCESSING; ELECTRICITY; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; SEALS

The invention relates to a method of outsourcing intermediate results of an internal data processing to an external memory, to a corresponding device for processing data having an interface for outsourcing intermediate results, to a disk drive having a corresponding device for processing data, and a cellular phone having a device for processing data. This method can be applied when confidential data is processed but intermediate results thereof need to be stored externally to the processing. First intermediate result data units (I1) are combined with first verification data units (V1) in order to provide a data signal (S1), which is encrypted (E1) and stored in an external memory (5). When the intermediate result data units (I1) stored in the external memory (5) are needed during a subsequent internal data processing a data signal (E2) is read from the external memory (5). After the decryption of the read data signal second verification data units (V2) and second intermediate result data units (I2) are obtained. Said second read verification data units (V2) are verified with said first verification data units (V1) in order to detect any manipulation of the intermediate result data during the time that they were stored in the external memory (5).