This study presents a modified majority-logic decodingalgorithm of Reed-Muller (RM) codes for matrix embedding (ME) in steganography. An ME algorithm uses linear block code to improve the embedding efficiency in steg...
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This study presents a modified majority-logic decodingalgorithm of Reed-Muller (RM) codes for matrix embedding (ME) in steganography. An ME algorithm uses linear block code to improve the embedding efficiency in steganography. The optimal embedding algorithm in steganography is equivalent to the maximumlikelihooddecoding (MLD) algorithm in error-correcting codes. The main disadvantage of ME is that the equivalent MLD algorithm of lengthy embedding codes requires highly complex embedding. This study used RM codes to embed data in binary host images. The authors propose a novel low-complexity embedding algorithm that uses a modified majority-logic algorithm to decode RM codes, in which a message-passing algorithm (i.e. sum-product, min-sum, or bias propagation) is performed on the highest order of information bits in the RM codes. The experimental results indicate that integrating bias propagation into the proposed scheme achieves superior embedding efficiency (relative to when the sum-product or min-sum algorithm is used) and can even achieve the embedding bound of RM codes.
Variable-length error-correcting codes, suitable to perform joint source-channel coding, are presented. A maximum likelihood decoding algorithm for these codes is given. Some performance bounds are derived and it is s...
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Variable-length error-correcting codes, suitable to perform joint source-channel coding, are presented. A maximum likelihood decoding algorithm for these codes is given. Some performance bounds are derived and it is shown that these codes are similar to convolutional codes. The free distance of these codes is defined and it is shown that it is the most important parameter that determines their performance at high E-b/N-o. It is shown that the performance of these codes can be better than a standard cascade of a Huffman code followed by a BCH code with the same code parameters.
An efficient maximum likelihood decoding algorithm on the Z-channel is proposed. It is shown that the algorithm needs a smaller number of calculations and also a smaller size of memory than the conventional methods.
An efficient maximum likelihood decoding algorithm on the Z-channel is proposed. It is shown that the algorithm needs a smaller number of calculations and also a smaller size of memory than the conventional methods.
Space-time coded systems for Rayleigh flat fading environments are considered, in which the signal arrivals from each transmit antenna to a receive antenna are different. For this situation, a maximumlikelihood (ML) ...
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Space-time coded systems for Rayleigh flat fading environments are considered, in which the signal arrivals from each transmit antenna to a receive antenna are different. For this situation, a maximumlikelihood (ML) decodingalgorithm for space-time codes which considers the arrival differences is proposed. The simulation results show that the proposed algorithm considerably outperforms the conventional one.
In this paper we consider low-density parity-check (LDPC) codes with special construction. We obtain the lower-bounds on the error exponents for these codes under proposed low-complexity decodingalgorithm and under a...
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ISBN:
(纸本)9781538693605
In this paper we consider low-density parity-check (LDPC) codes with special construction. We obtain the lower-bounds on the error exponents for these codes under proposed low-complexity decodingalgorithm and under a well known maximum likelihood decoding algorithm. We show that such LDPC code with special construction exists, that the error probability of the low-complexity decodingalgorithm exponentially decreases with the code length for all code rates below the channel capacity. We also show that obtained lower-bound on the error exponent under the maximumlikelihooddecoding almost reaches the lower-bound on the error exponent of good linear codes under the maximumlikelihooddecoding. The error exponents are computed numerically for different code parameters.
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