Wet Paper Codes Research Articles

Wet Paper Coding-Based Deep Neural Network Watermarking.

In recent years, the wide application of deep neural network models has brought serious risks of intellectual property rights infringement. Embedding a watermark in a network model is an effective solution to protect intellectual property rights. Although researchers have proposed schemes to add watermarks to models, they cannot prevent attackers from adding and overwriting original information, and embedding rates cannot be quantified. Therefore, aiming at these problems, this paper designs a high embedding rate and tamper-proof watermarking scheme. We employ wet paper coding (WPC), in which important parameters are regarded as wet blocks and the remaining unimportant parameters are regarded as dry blocks in the model. To obtain the important parameters more easily, we propose an optimized probabilistic selection strategy (OPSS). OPSS defines the unimportant-level function and sets the importance threshold to select the important parameter positions and to ensure that the original function is not affected after the model parameters are changed. We regard important parameters as an unmodifiable part, and only modify the part that includes the unimportant parameters. We selected the MNIST, CIFAR-10, and ImageNet datasets to test the performance of the model after adding a watermark and to analyze the fidelity, robustness, embedding rate, and comparison schemes of the model. Our experiment shows that the proposed scheme has high fidelity and strong robustness along with a high embedding rate and the ability to prevent malicious tampering.

Reversible Data Hiding in Encrypted Color Halftone Images with High Capacity

In recent years, reversible data hiding (RDH) has become a research hotspot in the field of multimedia security that has aroused more and more researchers’ attention. Most of the existing RDH algorithms are aiming at continuous-tone images. For RDH in encrypted halftone images (RDH-EH), the original cover image cannot be recovered losslessly after the watermark is extracted. For some application scenarios such as medical or military images sharing, reversibility is critical. In this paper, a reversible data hiding scheme in encrypted color halftone images (RDH-ECH) is proposed. In the watermark embedding procedure, the cover image is copied into two identical images to increase redundancy. We use wet paper code to embed the watermark into the image blocks. Thus, the receiver only needs to process the image blocks by the check matrices in order to extract the watermarks. To increase embedding capacity, we embed three layers in the embedding procedure and combine the resulting images into one image for convenience of transmission. From the experimental results, it can be concluded that the original image can be restored entirely after the watermarks are extracted. Besides, for marked color halftone images, our algorithm can implement high embedding capacity and moderate visual quality.

A Novel Three-Layer QR Code Based on Secret Sharing Scheme and Liner Code

Quick Response (QR) code, a machine-readable symbol, is widely employed in all walks of life due to its large information capacity, strong error correction ability, and fast reading speed. However, anyone with a standard decoder could obtain stored information. In this paper, utilizing the characteristics of the Hamming code, wet paper code, and the recognition mechanism of the QR code, we introduce a high-capacity QR code with three-layer information to protect the sensitive information. In the proposed scheme, we utilize the XOR-based secret-sharing algorithm to embed the second-layer information on the column vector of the constructed random matrix block. Then, without affecting the embedding result of the second layer information, the matrix block elements are reused again, and the Hamming code is constructed with the column vector. Based on the error correction mechanism of the Hamming code, the third layer of information is embedded on the column vector and encoded by wet paper coding to realize the blind extraction. Finally, based on the recognition mechanism of the QR code, the random matrix block containing the secret information is fused with the carrier QR code, and the public information of the carrier QR code is used as the first-layer information. Compared with other schemes, the proposed scheme has the advantages of high information payload, low computational complexity, and strong robustness.

An Enhanced Steganographic Code and its Application in Voice-Over-IP Steganography

Voice-over IP (VoIP) technology is a kind of digital transmission technology based on IP network. It is one of the important methods to use voice service in VoIP as steganographic carrier to ensure secure transmission. However, the traditional steganographic code has some problems, such as low embedding efficiency and weak concealment, which cannot meet the requirements of VoIP streaming media information hiding for the security of secret information. Therefore, a steganographic algorithm combining F5 and simplified wet paper code (SWPC) algorithm is proposed. The main idea is to embed secret messages in each row of the carrier matrix using the F5 algorithm, and then the SWPC algorithm is used to embed the columns according to the wet and dry characteristics of the wet paper code without affecting the results before row embedding. We use the VoIP streams encoded by the ITU-T G.729a codec as a carrier to verify the proposed scheme. The experimental results demonstrate that the proposed scheme can achieve relatively better IP speech data steganographic transparency and that it can outperform F5-WPC and SWPC approaches.

Improved Wet Paper Code Using Simplified Hamming Parity-Check Matrix and Its Application in Voice-over-IP Steganography

Wet paper code (WPC) can adaptively select the covert channel, but the computational complexities of existing solving algorithms are too large to satisfy the real-time requirement of Voice over IP (VoIP). For this reason, an improved WPC method based on simplified hamming parity-check matrix is presented. The main idea is to determine the required encoding matrix using a simplified hamming parity-check matrix and randomly expand the encoding matrix to the cover matrix according to the given cover length. Compared with the existing ones, the proposed method can effectively reduce computational complexity to only O(n), and obtain an optimal solution in any case. Moreover, it can be adapted to different cover lengths by adjusting the number of columns needed to be inserted. Employing the improved WPC, we further design a steganographic scheme without carrier negotiation for VoIP. We evaluate the proposed scheme with ITU-T G.729a as the codec of the cover speech in StegVoIP that is a prototypical covert communication system based on VoIP, and compare it with traditional approaches. The experimental results demonstrate that the proposed scheme can achieve relatively high embedding efficiency and steganographic transparency while adequately satisfying real-time requirement of VoIP services, and outperforms the traditional approaches.

Lossless and Reversible Data Hiding in Encrypted Images With Public-Key Cryptography

This paper proposes lossless, reversible, and combined data hiding schemes for ciphertext images encrypted by public-key cryptosystems with probabilistic and homomorphic properties. In the lossless scheme, the ciphertext pixels are replaced with new values to embed the additional data into several least significant bit planes of ciphertext pixels by multilayer wet paper coding. Then, the embedded data can be directly extracted from the encrypted domain, and the data-embedding operation does not affect the decryption of original plaintext image. In the reversible scheme, a preprocessing is employed to shrink the image histogram before image encryption, so that the modification on encrypted images for data embedding will not cause any pixel oversaturation in plaintext domain. Although a slight distortion is introduced, the embedded data can be extracted and the original image can be recovered from the directly decrypted image. Due to the compatibility between the lossless and reversible schemes, the data-embedding operations in the two manners can be simultaneously performed in an encrypted image. With the combined technique, a receiver may extract a part of embedded data before decryption, and extract another part of embedded data and recover the original plaintext image after decryption.

LOSSLESS AND REVERSIBLE DATA HIDING IN ENCRYPTED IMAGES WITH PUBLIC KEY CRYPTOGRAPHY

A lossless, reversible, and combined data hiding schemes for ciphertext images encrypted by public key cryptosystems with probabilistic and homomorphic properties is proposed. In the lossless scheme, the ciphertext pixels are replaced with new values to embed the additional data into several LSB-planes of ciphertext pixels by multi-layer wet paper coding. Then, the embedded data can be directly extracted from the encrypted domain, and the data embedding operation does not affect the decryption of original plaintext image. In the reversible scheme, a preprocessing is employed to shrink the image histogram before image encryption, so that the modification on encrypted images for data embedding will not cause any pixel oversaturation in plaintext domain. Although a slight distortion is introduced, the embedded data can be extracted and the original image can be recovered from the directly decrypted image. Due to the compatibility between the lossless and reversible schemes, the data embedding operations in the two manners can be simultaneously performed in an encrypted image. With the combined technique, a receiver may extract a part of embedded data before decryption, and extract another part of embedded data and recover the original plaintext image after decryption.

LOSSLESS AND REVERSIBLE DATA HIDING IN ENCRYPTED IMAGES WITH PUBLIC KEY CRYPTOGRAPHY

In this paper, system uses the cryptography and steganography concept, which proposes a lossless, reversible, and combined data hiding methods for images encrypted by public key cryptosystems with probabilistic and homomorphic properties. In the lossless method, pixels of encrypted images are replaced with new values to embed additional data into LSB-planes of ciphertext pixels by multiple layer wet paper coding. Thus, original data can be directly extracted from encrypted image, and the data embedding does not affect the decryption of plaintext image. In the reversible method, histogram shrink is done before image encryption, so that the modification on cipher text images for data embedding will not cause any loss in plaintext image. With the combined lossless and reversible technique, receivers extract a part of embedded data before decryption, extract another part of embedded data and recover the original plaintext image after decryption. Keywords: Lossless, reversible, encryption, data hiding, decryption Cite this Article Amrtha Anand K, Dheena Kurien . Lossless and Reversible Data Hiding in Encrypted Images with Public Key Cryptography . Current Trends in Information Technology . 2016; 6(2): 27–33p.

Image-Like 2D Barcodes Using Generalizations of the Kuznetsov–Tsybakov Problem

In this paper, we propose a novel method for generating visually appealing two-dimensional (2D) barcodes that resemble meaningful images to human observers. The technology of 2D barcodes, currently dominated by quick response codes, is widely adopted in many applications, including product tracking, document management, and general marketing. Such barcodes typically lack user friendly appearance and do not convey any visual significance to human observers. The proposed method addresses this problem by allowing 2D barcodes to resemble an arbitrary image or a logo. Our method is based on a generalization of the Kuznetsov–Tsybakov problem that served as a foundation for wet paper codes, commonly adopted in digital steganography. We introduce weaker statistical constraints to obtain additional flexibility allowing the barcode to assume the appearance of an arbitrary pattern. This paper provides the theoretical analysis of the proposed coding framework and a practical algorithm for rapid approximation of the optimal code. We also discuss the introduction of error correction capabilities, and experimentally evaluate a prototype implementation in a smartphone-based acquisition scenario.

A Secure Image Steganographic Method in Encrypted Domain

A new secure image steganographic algorithm for encrypted domain steganography is proposed based on fully homomorphic encryption and double-layer embedding.The proposed method can reach the capacity of classical steganography while resist to statistical steganalysis both in plaintext domain and encrypted domain.At first,a novel double-layered embedding algorithm based on adaptive steganography and Wet Paper Codes(WPCs) is constructed for plaintext embedding.Then an fully homomorphic encryption algorithm is modified to encrypt the stego image.Finally,the embedding message is extracted in encrypted domain.The performance analysis and experimental results show that the steganographic security of the proposed method preserves well performance under several attacking conditions,including both steganographic/encrypted keys leakage,encrypted keys leakage and no keys leakage.

Steganographic Method with High Visual Concealment in Wavelet Domain

In this paper we propose a new steganographic method, which based on wet paper codes and wavelet transformation. The method is designed to embed secret messages in images' wavelet coefficients and depends on images' texture characters in local neighborhood. The receivers can extract secret bits from carrier images only by some matrix multiplications without knowing the formulas written by senders, which further improves steganographic security and minimizes the impact of embedding changes. The experimental results show that our proposed method has good robust and visual concealment performance and proves out it's a practical steganographic algorithm.

An Efficient Adaptive Image Steganographic Method for ± k Embedding

Adaptive steganography which avoids changing the sensitive area in carrier, can efectively improve the security of steganography. Firstly, the schemes of side information synchronization in adaptive steganography are summarized and analyzed. Secondly, using the freedom degree which is extented by the previous one-way texture functions, a new orderpreserving texture function as side information of adaptive steganography is constructed. Finally, by combining wet paper codes and the method of multi-layered embedding, ± 1 algorithm and ± 2 algorithm are proposed. The proposed scheme can efciently enhance the security of adaptive steganography while maintaining fast side information synchronization between communicators. Theoretical analysis and experimental results show the efciency of the proposed scheme.

A Steganographic Method Based on Double Layers Wet Paper Code in IWT Domain

Based on wet paper code, integer wavelet and matrix coding, this paper constructs a new steganographic algorithm. Combine with the advantage in integer wavelet domain, which more close to HVS, a part of secret messages are embedded by LSB in high-frequency coefficients after integer wavelet switch, wet paper code is used to change the direction of embedding. Another part of secret messages are embedded by matrix coding in low-frequency coefficients after integer wavelet switch, wet paper code is still used to change the direction of embedding. The performance of the proposed approach shows that security and capacity of secret messages are improved in integer wavelet domain.

Minimizing Additive Distortion in Steganography Using Syndrome-Trellis Codes

This paper proposes a complete practical methodology for minimizing additive distortion in steganography with general (nonbinary) embedding operation. Let every possible value of every stego element be assigned a scalar expressing the distortion of an embedding change done by replacing the cover element by this value. The total distortion is assumed to be a sum of per-element distortions. Both the payload-limited sender (minimizing the total distortion while embedding a fixed payload) and the distortion-limited sender (maximizing the payload while introducing a fixed total distortion) are considered. Without any loss of performance, the nonbinary case is decomposed into several binary cases by replacing individual bits in cover elements. The binary case is approached using a novel syndrome-coding scheme based on dual convolutional codes equipped with the Viterbi algorithm. This fast and very versatile solution achieves state-of-the-art results in steganographic applications while having linear time and space complexity w.r.t. the number of cover elements. We report extensive experimental results for a large set of relative payloads and for different distortion profiles, including the wet paper channel. Practical merit of this approach is validated by constructing and testing adaptive embedding schemes for digital images in raster and transform domains. Most current coding schemes used in steganography (matrix embedding, wet paper codes, etc.) and many new ones can be implemented using this framework.

Wet paper codes and the dual distance in steganography

In 1998 Crandall introduced a method based on coding theory to secretly embed a message in a digital support such as an image. Later, in 2005, Fridrich et al. improved this method to minimize the distortion introduced by the embedding; a process called wet paper. However, as previously emphasized in the literature, this method can fail during the embedding step. Here we find sufficient and necessary conditions to guarantee a successful embedding, by studying the dual distance of a linear code. Since these results are essentially of combinatorial nature, they can be generalized to systematic codes, a large family containing all linear codes. We also compute the exact number of embedding solutions and point out the relationship between wet paper codes and orthogonal arrays.

A Histogram-preserving Steganography Based on Wet Paper Coding and Graphic Matching Theory

该文结合隐写码、湿纸码和图匹配理论提出一种具有高嵌入效率的且可保持载体图像一阶直方图的双层嵌入隐写算法。首先构造出一条新的四进制的隐写信道，然后在该信道的LSB(Least Significant Bit)层和次LSB层分别使用二元隐写码和湿纸码嵌入秘密消息，这样即可确定出需要修改的元素，接着构造出一个图，最后使用图论中匹配算法寻找一种减小失真且保持直方图的修改方式。性能分析和实验结果表明：在嵌入相同长度秘密消息的情况下，新算法的PSNR、嵌入效率和保持一阶直方图效果均优于隐写软件Steghide。

Generalization and Analysis of the Paper Folding Method for Steganography

Wet paper codes (WPCs) are designed for steganography, in which the sender and recipient do not need to share the changeable positions. In this paper, we propose the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> -page construction for wet paper coding, which can generate a family of WPCs following the upper bound on embedding efficiency from one single WPC. The Paper Folding method, one of our previous methods, is a special case of the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> -page construction with <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> =2 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> . We deduce recursions for calculating embedding efficiency of <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> -page construction, and obtain explicit expression on embedding efficiency of 2 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> -page construction. Furthermore, we derive the limit of distance between the embedding efficiency of 2 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> -page construction and the upper bound of embedding efficiency as <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</i> tends to infinity. Based on the limit, we analyze how the embedding efficiency is influenced by the proportion of wet pixels (wet ratio) in the cover, showing that embedding efficiency only drops about 0.32 as the wet ratio increases to 0.9999.

Near-Optimal Codes for Information Embedding in Gray-Scale Signals

High-performance steganography requires large embedding rate and small distortion, i.e., high embedding efficiency. Steganographic codes (stego-codes) derived from covering codes can improve embedding efficiency. In this paper, a new method is proposed to construct binary stego-codes for LSB embedding in gray-scale signals, which shows that not just one but a family of stego-codes can be generated from a covering code by combining Hamming codes and wet paper codes. This method can greatly expand the set of embedding schemes as applied to steganography. Performances of stego-code families (SCF) of structured codes and random codes are analyzed. SCFs of random codes can approach the rate-distortion bound on LSB embedding for any chosen embedding rate. Furthermore, SCFs are modified for applications in ±1 embedding, and a treble layered embedding method for ±2 embedding is obtained. By combining the modified SCFs and the treble layered method, a near-optimal scheme for ±2 embedding is presented.

A Steganographic Algorithm Based on Hamming Code and Wet Paper Code

该文通过将载体图像分割成矩阵块，重复利用载体矩阵块像素，结合汉明码和湿纸码构造了一种新的双层结构隐写算法。该算法首先利用汉明码在载体矩阵的行向量中嵌入信息，然后在列向量上根据是否影响前面嵌入结果以及是否需要3个修改引入dry和wet的概念，并通过构造伪随机二值矩阵，采用湿纸码在列向量上实现二次嵌入，从而获得较好的隐写性能。实验结果表明：该隐写算法在嵌入率为0.1至0.8 bpp范围内，性能优于PPC和F5算法。

Improving the Embedding Efficiency of Wet Paper Codes by Paper Folding

Wet paper codes are used to design steganographic schemes, in which the sender can embed messages into a cover with arbitrarily selected changeable bits that are not shared by the recipient. In this letter, we propose a novel approach to wet paper codes by folding the cover into several layers and applying basic wet paper coding methods with low computational complexity to each layer. This method uses the changes introduced in the first layer to embed messages into every layer and therefore achieves high embedding efficiency (average number of bits embedded by per change).