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• An adaptive HEVC video steganography algorithm is designed, which can effectively resist the PU shift-based steganalysis. • The introduction of multivariate STC allows for smaller modifications with the same embedding capacity. • The superiority of this algorithm over the state-of-the-art video steganography algorithm is verified through extensive experiments. Calibration-based steganalysis methods are a fatal threat to current HEVC steganography algorithms. The current steganography algorithms based on prediction unit (PU) still lack resistance to this type of steganalysis. The reason is that the improvements in HEVC codec provide more potential steganographic space as well as introduce more detectable distortion. Therefore, a HEVC video steganography method that has resistance to PU shift-based steganalysis is proposed in this paper. First, the PU shift phenomenon that exists in PU-based steganography is introduced. Then the existing calibration-based steganalysis method is enhanced. According to the encoding rules of HEVC, the distortion cost function according to the difference of rate distortion cost (RD cost) during recompression is designed, which aims to obtain better resistance to calibration-based steganalysis. Experimental results demonstrate that the steganography algorithm designed in this paper provides excellent resistance ability for calibration-based steganalysis. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel joint image compression and encryption scheme based on JPEG standard. We realize image encryption at JPEG’s transformation stage. Instead of only using 8 × 8 discrete cosine transform (DCT) for transformation, we generate new orthogonal transforms by embedding an extra rotation angle of π to different stages’ butterflies in 8 × 8 DCT’s flow-graph, and then apply them alternatively for transformation according to a predefined secret key. By carefully controlling the number of rotation angles embedded, the quality control of encrypted images can also be achieved. The encryption algorithm is further enhanced by performing block permutation before the entropy encoding stage. Extensive experiments have been conducted to show the good protection and compression performance of our encryption schemes. Finally, a detailed security analysis is provided to show the encryption schemes’ resistance to various cryptanalysis methods, such as brute-force attack, key sensitivity analysis, replacement attack and statistical attack. [ABSTRACT FROM AUTHOR]

One of the general ways in designing a secure image encryption algorithm based on chaos theory is to derive a number of round subkeys from the Key Schedule algorithm under the control of an external secret key. A compulsory condition for the security of an image encryption algorithm is that the length of the external secret key should be sufficiently long in terms of bitlength. However, the sufficiently long secret key is not a guarantee that the algorithm is secure. In this paper, we emphasize the importance in designing a secure Key Schedule algorithm for such image based encryption techniques. Notably, we show why the effective space spanned by the subkeys should never be smaller than the external secret key space. To highlight the importance of this, we present our attacks on three recently proposed image encryption schemes. [ABSTRACT FROM AUTHOR]

Cover selection is one of the important techniques to improve the security of image steganography. However, existing methods mostly focus on cover selection of grayscale image. In this paper, we propose a novel Cover Selection Algorithm of color images based on Hybrid Local Texture Descriptor, named HLTD-CSA. A green-channel related Local Binary Pattern (LBP) is designed which utilizes local statistics of intra-channel and cross-channel correlations efficiently. Besides, Local Phase Quantization is introduced to serve as a complementary component of our improved LBP. To further enhance the performance of cover selection for color image, a hybrid local texture descriptor (HLTD) is obtained by combining these two types of local texture descriptors with a proper combination strategy. Finally, the proposed algorithm selects images which have larger values of HLTD to construct the cover image set. Extensive experiments are conducted to verify the effectiveness of our method. • A cover selection method of color image is proposed using hybrid texture descriptor. • A novel local binary pattern is designed with intra- and cross-channel correlations. • Descriptors in spatial and frequency domains are combined with a proper strategy. • Experiments verify the efficiency of improving steganography security by our method. [ABSTRACT FROM AUTHOR]

Abstract: Recently, an encryption algorithm using multiple Huffman tables was proposed to protect multimedia content. Since the encryption operation can be efficiently implemented, its speed is several times faster than AES (Advanced Encryption Standard) or any known stream ciphers. In this paper, the security of this algorithm will be analyzed in detail. It is shown that the key is recovered with one ciphertext and the corresponding plaintext consisting of about 10 blocks of symbols by known-plaintext attack or with thousands of ciphertexts by ciphertext-only attack. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new reversible VQ-based hiding scheme that can recover the original VQ compressed codes after data extraction. Our scheme sorts a VQ codebook using the referred counts. The VQ codebook is then divided into 2 B clusters and half of these clusters are used to embed secret data, in which B denotes the size of the secret data embedded into each VQ index. Compared to Chang et al.’s scheme, which divides a sorted VQ codebook into 2 B −1 ×3 clusters and uses the front one-third clusters to embed secret data, our method can embed more data. Moreover, indicator, index exchanging, and side-match prediction schemes are proposed to further improve our scheme. Under the same sorted VQ codebook, the experimental results demonstrate that our data hiding algorithm has higher capacities and better compression rates. [Copyright &y& Elsevier]

• Employ multiple image features to depict image complexity, and propose the new computing method of steganographic capacity. • A novel embedding strategy is proposed, in which we select image with high capacity in priority. • Experiment results show the new proposed strategy can obtain better performance. Data hiding in multiple images has been a significant research direction in information security. How to reasonably design the embedding strategy to spread the payload among multiple images is still an open issue. In this paper, we propose an embedding strategy on fusing multiple features. We utilize the typical characteristic parameters of gray level co-occurrence matrix, the image entropy and the shape parameter to describe image complexity. Furthermore, we combine with the number of cover images, the number of cover images assigned to steganographer and the size of cover image to estimate the steganographic capacity of each image. The strategy is implemented together with some state-of-the-art single image steganographic algorithms. Experimental results demonstrate that the security performance of the proposed strategy is higher than that of the state-of-the-art embedding strategy against the blind universal pooled steganalysis. [ABSTRACT FROM AUTHOR]

• A novel natural steganographic scheme for haze images by making embedding modifications mimic the transition of weather effects. • A physically valid cover-source switching algorithm for natural steganography of haze images. • Two steganographic embedding methods for floating-point images in spatial-domain based on the textural complexity. In realistic outdoor scenarios, image sensors tend to suffer from various weather conditions (e.g., haze, rain, etc.),which make the images of the same scene taken at different times may be different. Therefore, one should be able to securely embed secret messages into these images by making use of the variations of the weather effects. Inspired by some recent natural steganography algorithms, this paper presents a novel haze image steganography method, which embeds messages through adjusting the weather effects of an input haze image, making it resemble the same image captured under another weather condition. The proposed steganography method consists of three parts: (1) model parameter estimation of the input haze image, (2) haze effects adjustment according to the atmospheric scattering model, (3) message embedding using the floating-point adjusted haze image. 10,000 haze images captured under different haze conditions in various scenarios were used to test the proposed steganography algorithm. The experimental results show that the proposed steganography algorithm is more secure than S-UNIWARD and HILL for steganalyzers who only have raw haze images. [ABSTRACT FROM AUTHOR]