摘要:
The invention relates to an information carrier for holding user information, the information carrier comprising access information for accessing the user information, the access information being stored in a pre-determined first region on the information carrier. The information carrier further comprises at least one further region different from the first region, the further region comprising dummy information. The invention is based on the insight that the noise level of a read out signal increases somewhat in the region(s) where the access information is hidden. To avoid this difference in noise level between regions with and without the access information, this access information is assigned for only a specific region of the information carrier, but dummy information is also written in other regions. Due to this, an improved copy protection system against illegal read out of the user information present or to be present on the information carrier is realized.
摘要:
The invention relates to an information carrier for holding user information, the information carrier comprising access information in the form of access information bits for accessing the user information, the access information bits being stored on the information carrier in a variation of a parameter, which variation is detectable by integration detection. The access information bits are scrambled according to a pre-determined scrambling method. By scrambling the access information bits according to a pre-determined scrambling method detection of the access information is not possible as long as the scrambling method is not known. Using the integration detection technique only results in the access information is one knows how the signal obtained after reading-out the area comprising the access information bits must be processed. In this way illegal retrieval of the user information is further prevented.
摘要:
An information carrier for holding user information includes access information for accessing the user information, the access information being stored in a pre-determined first region on the information carrier. The information carrier further includes at least one further region different from the first region, the further region comprising dummy information.
摘要:
An information carrier for holding user information includes access information for accessing the user information, the access information being stored in a pre-determined first region on the information carrier. The information carrier further includes at least one further region different from the first region, the further region comprising dummy information.
摘要:
An information carrier for holding user information includes access information for accessing the user information, the access information being stored in a pre-determined first region on the information carrier. The information carrier further includes at least one further region different from the first region, the further region comprising dummy information.
摘要:
An information carrier for holding user information, the information carrier comprising access information in the form of access information bits for accessing the user information, the access information bits being stored on the information carrier in a variation of a parameter, which variation is detectable by integration detection. The access information bits are scrambled according to a pre-determined scrambling method. By scrambling the access information bits according to a pre-determined scrambling method, detection of the access information is not possible as long as the scrambling method is not known. Using the integration detection technique, the only way to obtain the access information is by knowing how the signal obtained after reading-out the area comprising the access information bits must be processed. In this way illegal retrieval of the user information is further prevented.
摘要:
The invention relates to a method of encoding user data into codevectors and to a corresponding method of decoding codevectors into user data. In order to be able to use the same ECC decoder for decoding of more than one type of data a method of encoding is proposed comprising the steps of: a) generating a first block of a fixed first number of data symbols by taking a fixed second number, being smaller than said first number, of user data symbols, and a fixed third number of dummy data symbols, and by arranging said user data symbols and said dummy data symbols in a predetermined order, b) encoding said first block of data symbols using an ECC encoder (2) to obtain a codeword having a fixed number of symbols, said codeword comprising said first block of data symbols and a second block of a fixed forth number of parity symbols, and (c) generating a codevector by selecting a fifth predetermined number of user data symbols and a sixth predetermined number of parity symbols from said codeword, the sum of said fifth and sixth number being predetermined and smaller than the sum of said second and forth number.
摘要:
A demodulating system (100) for demodulating a phase-modulated input signal (Si) comprises: a complex demodulator (110), having a first input (111) for receiving the phase-modulated input signal (Si) and being designed to perform complex multiplication of this signal with an approximation of the inverse of the phase modulation; a spectrum analyzing device (130) receiving the demodulated product signal produced by the complex demodulator (110) and capable of analyzing the frequency spectrum of the demodulated product signal.
摘要:
The invention relates to a method of encoding user data into codevectors and to a corresponding method of decoding codevectors into user data. In order to be able to use the same ECC decoder for decoding of more than one type of data a method of encoding is proposed comprising the steps of: generating a first block of a fixed first number of data symbols by taking a fixed second number, being smaller than said first number, of user data symbols, and a fixed third number of dummy data symbols, and by arranging said user data symbols and said dummy data symbols in a predetermined order, encoding said first block of data symbols using an ECC encoder (2) to obtain a codeword having a fixed number of symbols, said codeword comprising said first block of data symbols and a second block of a fixed forth number of parity symbols, and generating a codevector by selecting a fifth predetermined number of user data symbols and a sixth predetermined number of parity symbols from said codeword, the sum of said fifth and sixth number being predetermined and smaller than the sum of said second and forth number.
摘要:
An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.