Detectability Improved Tamper Detection Scheme for Absolute Moment Block Truncation Coding Compressed Images

Abstract

Since digital media is gaining popularity nowadays, people are more concerned about its integrity protection and authentication since tampered media may result in unexpected problems. Considering a better media protection technique, this paper proposes an efficient tamper detection scheme for absolute moment block truncation coding (AMBTC) compressed images. In AMBTC, each image block is represented by two quantization levels (QLs) and a bitmap. Requiring insignificant computation cost, it attracts not only a wide range of application developers, but also a variety of studies to investigate the authentication of its codes. While the existing methods protect the AMBTC codes to a large extent, the leakage of some unprotected codes may be insensitive to intentional tampering. The proposed method fully protects the AMBTC codes by embedding authentication codes (ACs) into QLs. Meanwhile, the most significant bits of QLs are symmetrically perturbed to generate the candidates of ACs. The ACs that cause the minimum distortion are embedded into the least significant bits of QLs to minimize the distortion. When compared with prior works, the experimental results reveal that the proposed method offers a significant sensitivity-of-tamper property while providing a comparable image quality.

High-Precision Authentication Scheme Based on Matrix Encoding for AMBTC-Compressed Images

“…In Lin et al's scheme [29] and Hong et al's scheme [30], the stego-images' quality with the four-bit authentication code has average PSNRs of 33.07 and 32.33 dB, respectively. Also, we can observe that Hong et al's scheme [31] proposes two embedding strategies that can embed an eight-bit authentication code into each block, resulting in a TDR of 99.61% and average PSNRs of 28.92 and 29.84 dB. Meanwhile, with the same size of the authentication code, i.e., six bits, our proposed scheme and the Hong et al scheme [31] have the same effect with respect to the TDR.…”

“…Also, we can observe that Hong et al's scheme [31] proposes two embedding strategies that can embed an eight-bit authentication code into each block, resulting in a TDR of 99.61% and average PSNRs of 28.92 and 29.84 dB. Meanwhile, with the same size of the authentication code, i.e., six bits, our proposed scheme and the Hong et al scheme [31] have the same effect with respect to the TDR. The average PSNR of our approach is 0.39 dB higher than that of the LSBP scheme and 0.05 dB lower than that of the MSBP scheme.…”

“…Main Limitation [26] 93.75 Yes Scheme in [27] 93.75 No Scheme in [28] 93.75 Yes Scheme in [29] 93.75 Yes Compression codes' attack Scheme in [30] 93.75 Yes More computation Scheme in [31] 98 The rest of this paper is organized as follows: We briefly review related works in Section 2, including AMBTC compression technology and matrix encoding; in Section 3, we describe the proposed Symmetry 2019, 11, 996 5 of 24 scheme in detail; in Section 4, we perform a series of experiments to show the performance of our approach; finally, we provide conclusions in Section 5.…”

“…The same year, Hong et al [31] proposed two image authentication schemes, i.e., LSBP and MSBP, for tampering detection for AMBTC compression codes. For each block, their schemes can embed an (a + b)-bit authentication code generated from the bitmap and quantization levels' MSBs.…”

“…However, in a few cases, their scheme fails to authenticate the watermarked image due to having broken the natural correlation between quantization levels. Table 1 gives summaries of those authentication schemes [23,[25][26][27][28][29][30][31]. In short, some of them [26,[28][29][30] need to store a reference matrix during the AC embedding and authentication phase, and some schemes [23,[25][26][27][28][29] have a limitation against the compression codes' attack or collage attack.…”