This paper proposes a novel authentication scheme for absolute moment block truncation coding (AMBTC) of a compressed image using turtle shell based data hiding. For simplicity, we call it turtle shell based image aut...
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This paper proposes a novel authentication scheme for absolute moment block truncation coding (AMBTC) of a compressed image using turtle shell based data hiding. For simplicity, we call it turtle shell based image authentication method (TSIA in short). For each block, a 3-bit authentication code (AC) is generated by combining the bitmap with a pseudo-random sequence and is concealed into the corresponding quantization levels with the use of a reference matrix. In order to solve the problem of having a high quantization level lower or equal to a low quantization level caused after the hiding operation, an iterative embedding mechanism is employed in the proposed TSIA scheme. Experimental results demonstrate that the proposed TSIA scheme outperforms previous works in the watermarked image quality with an increased PSNR of 0.16 dB and achieves high tampering detecting accuracy.
The error control of random network coding has recently received a lot of attention because its solution can increase robustness and reliability of data transmission. To achieve this, additional overhead is needed for...
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The error control of random network coding has recently received a lot of attention because its solution can increase robustness and reliability of data transmission. To achieve this, additional overhead is needed for error correction. In this paper, we design a compressed error and erasure correcting scheme to decrease the additional overhead of error correction. This scheme reduces the computation overhead dramatically by employing an efficient algorithm to detect and delete linearly dependent received packets in the destination node. It also simplifies the hardware operations when the scheme reduces the received matrix Y to form E-k(Y ) instead of E(Y ) in the decoding process. If at most r original packets get combined in k packets of one batch, the payload of one packet can increase from M-k to M-O(rlog(q)k) for the application of compressed code, where M is the packet length. In particular, the decoding complexity of compressed code is O(rm) operations in an extension field F-q(m), which does not enhance the overall decoding complexity of the system. Finally, we also compare our scheme's performance with existing works. The numerical results and analyses illustrate the security and performance of our scheme. Copyright (c) 2011 John Wiley & Sons, Ltd.
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