Abstract: A recording control device that controls data recording in a recording medium including a plurality of recording blocks each composed of a plurality of recording units as a unit of the data recording, the recording control device comprising a recording controller configured to temporarily record after-error data in one recording block of the plurality of recording blocks as a save block if a predetermined recording block of the plurality of recording blocks has become a defective block in which the data recording is impossible due to occurrence of an error at a certain recording unit during sequential recording of data in recording units from a beginning recording unit in the predetermined recording block, the after-error data being data that originally should be recorded in the certain recording unit and in the recording unit subsequent to the certain recording unit in the predetermined recording block.

Abstract: Input picture data are encrypted with high secrecy and restoration against an error of encrypted data. An EXOR circuit 100 calculates input picture data and a pseudo random sequence and obtains encrypted data. The obtained encrypted data are held in an FF circuit 101. The FF circuit 101 is reset for each line. Counters 102 and 103 count for each line or each frame and are reset for each frame or at the beginning of a program. An encryption device 105 encrypts outputs of an FF circuit 104 that holds a fixed value, the counters 103 and 102, and the FF circuit 101 with a key (K) and generates a pseudo random sequence. A shift register 106 divides the bit sequence. The EXOR 100 calculates the output of the shift register 106 and the input picture data and obtains encrypted data. Since the encrypted output is fed back, data cannot be stolen using a successive input of the same data.

Abstract: An apparatus for enciphering data by which enciphered digital information data with improved cipher strength are obtained by subjecting digital information data to enciphered process responding to random number data or pseudo-random number data produced in accordance with key data, and which comprises an enciphering portion 40 for producing the enciphered digital information data, a cipher producing portion 45 for producing, in response to the key data, a cipher data from which random number data or pseudo-random number data are obtained to be supplied to the enciphering portion 40, a register 44 for supplying the cipher producing portion 45 with input data, and an initial value data generator 43 for supplying the register 44 with enciphered initial value data.

Abstract: An apparatus for enciphering data by which enciphered digital information data with improved cipher strength are obtained by subjecting digital information data to enciphered process responding to random number data or pseudo-random number data produced in accordance with key data, and which comprises an enciphering portion 40 for subjecting an HD signal to enciphering process to produce an enciphered HD signal, a cipher producing portion 45 for producing, in response to key data, a cipher data from which random number data or pseudo-random number data are obtained to be supplied to the enciphering portion 40, a register 44 for supplying the cipher producing portion 45 with input data, and a line number data extracting portion 43 for extracting line number data from the HD signal to be supplied to the register 44 as initial data.

Abstract: A method of enciphering data which is applicable to cipher-transmission of digital information data, in which the HD-SDI signal DHS is subjected to enciphering process using common key data DEY which is common to encipherment and decipherment to produce enciphered HD-SDI signal DHSE, the common key data DEY are subjected to enciphering process using open key data DOY to produce enciphered common key data DXY, and the enciphered HD-SDI signal DHSE accompanied with the enciphered common key data DXY are send to be transmitted, so that such a fear that the common key data DEY are eavesdropped on the transmission thereof can be effectively reduced.

Abstract: A method of transmitting data by which cipher-transmission of digital information data for which forbidden codes including timing identification codes are predetermined can be carried out with enciphered digital information data without containing undesirable forbidden code, in which digital information data contained in word sequence data which contain also time reference code data composed of the timing identification codes are subjected to enciphering process without producing the forbidden code to produce the enciphered digital information data which do not contain any forbidden code and then enciphered word sequence data are constituted with the enciphered digital information data and the time reference code data to be transmitted.